From 6e8c20f74cb41c4ea368cabf87cf4a00489c19f2 Mon Sep 17 00:00:00 2001
From: Rhys Evans <rhys.evans@ft.com>
Date: Sat, 27 Jul 2019 22:43:37 +0100
Subject: [PATCH 01/12] begin long job of adding debug logs

---
 package.json             |  1 +
 src/lib/compile-route.js | 11 +++++++++++
 src/lib/inspecting.js    |  3 +++
 3 files changed, 15 insertions(+)

diff --git a/package.json b/package.json
index d790d89d..04642d07 100644
--- a/package.json
+++ b/package.json
@@ -55,6 +55,7 @@
   "dependencies": {
     "babel-runtime": "^6.26.0",
     "core-js": "^3.0.0",
+    "debug": "^4.1.1",
     "glob-to-regexp": "^0.4.0",
     "lodash.isequal": "^4.5.0",
     "path-to-regexp": "^2.2.1",
diff --git a/src/lib/compile-route.js b/src/lib/compile-route.js
index 12d4e7d0..26a0d320 100644
--- a/src/lib/compile-route.js
+++ b/src/lib/compile-route.js
@@ -1,3 +1,4 @@
+const debug = require('debug')('fetch-mock')
 const generateMatcher = require('./generate-matcher');
 
 const matcherProperties = [
@@ -36,9 +37,11 @@ const argsToRoute = args => {
 };
 
 const sanitizeRoute = route => {
+	debug('Sanitizing route properties');
 	route = Object.assign({}, route);
 
 	if (route.method) {
+		debug(`Converting method ${route.method} to lower case`);
 		route.method = route.method.toLowerCase();
 	}
 	if (isUrlMatcher(route.matcher)) {
@@ -48,7 +51,11 @@ const sanitizeRoute = route => {
 
 	route.functionMatcher = route.matcher || route.functionMatcher;
 
+	debug('Setting route.identifier...')
+	debug(`- route.name is ${route.name}`)
+	debug(`- route.matcher is ${route.matcher}`)
 	route.identifier = route.name || route.url || route.functionMatcher;
+	debug(`=> route.identifier set to ${route.identifier}`);
 	return route;
 };
 
@@ -65,10 +72,13 @@ const validateRoute = route => {
 };
 
 const limitMatcher = route => {
+	debug('Limiting number of requests to handle by route');
 	if (!route.repeat) {
+		debug('No `repeat` value set on route. Will match any number of requests')
 		return;
 	}
 
+	debug(`Route set to repeat ${route.repeat} times`)
 	const matcher = route.matcher;
 	let timesLeft = route.repeat;
 	route.matcher = (url, options) => {
@@ -91,6 +101,7 @@ const delayResponse = route => {
 };
 
 const compileRoute = function(args) {
+	debug('Compiling route');
 	const route = sanitizeRoute(argsToRoute(args));
 	validateRoute(route);
 	route.matcher = generateMatcher(route);
diff --git a/src/lib/inspecting.js b/src/lib/inspecting.js
index 65baed9c..45cddbc3 100644
--- a/src/lib/inspecting.js
+++ b/src/lib/inspecting.js
@@ -1,3 +1,4 @@
+const debug = require('debug')('fetch-mock')
 const { normalizeUrl } = require('./request-utils');
 const FetchMock = {};
 const { sanitizeRoute } = require('./compile-route');
@@ -6,7 +7,9 @@ const isName = nameOrMatcher =>
 	typeof nameOrMatcher === 'string' && /^[\da-zA-Z\-]+$/.test(nameOrMatcher);
 
 const filterCallsWithMatcher = (matcher, options = {}, calls) => {
+	debug('/** Begin generating synthetic matcher for inspecting **/')
 	matcher = generateMatcher(sanitizeRoute(Object.assign({ matcher }, options)));
+	debug('/** End generating synthetic matcher for inspecting **/')
 	return calls.filter(([url, options]) => matcher(normalizeUrl(url), options));
 };
 

From 03cd63d96d9bce9b99825a8c7ad853b954cce025 Mon Sep 17 00:00:00 2001
From: Rhys Evans <rhys.evans@ft.com>
Date: Sat, 27 Jul 2019 23:01:12 +0100
Subject: [PATCH 02/12] avod compile debug logs when inspecting

---
 src/lib/compile-route.js | 14 +++++++-------
 src/lib/inspecting.js    |  5 +----
 2 files changed, 8 insertions(+), 11 deletions(-)

diff --git a/src/lib/compile-route.js b/src/lib/compile-route.js
index 26a0d320..49702aae 100644
--- a/src/lib/compile-route.js
+++ b/src/lib/compile-route.js
@@ -36,12 +36,12 @@ const argsToRoute = args => {
 	return routeConfig;
 };
 
-const sanitizeRoute = route => {
-	debug('Sanitizing route properties');
+const sanitizeRoute = (route, useDebugger = true) => {
+	useDebugger && debug('Sanitizing route properties');
 	route = Object.assign({}, route);
 
 	if (route.method) {
-		debug(`Converting method ${route.method} to lower case`);
+		useDebugger && debug(`Converting method ${route.method} to lower case`);
 		route.method = route.method.toLowerCase();
 	}
 	if (isUrlMatcher(route.matcher)) {
@@ -51,11 +51,11 @@ const sanitizeRoute = route => {
 
 	route.functionMatcher = route.matcher || route.functionMatcher;
 
-	debug('Setting route.identifier...')
-	debug(`- route.name is ${route.name}`)
-	debug(`- route.matcher is ${route.matcher}`)
+	useDebugger && debug('Setting route.identifier...')
+	useDebugger && debug(`- route.name is ${route.name}`)
+	useDebugger && debug(`- route.matcher is ${route.matcher}`)
 	route.identifier = route.name || route.url || route.functionMatcher;
-	debug(`=> route.identifier set to ${route.identifier}`);
+	useDebugger && debug(`=> route.identifier set to ${route.identifier}`);
 	return route;
 };
 
diff --git a/src/lib/inspecting.js b/src/lib/inspecting.js
index 45cddbc3..3e763829 100644
--- a/src/lib/inspecting.js
+++ b/src/lib/inspecting.js
@@ -1,4 +1,3 @@
-const debug = require('debug')('fetch-mock')
 const { normalizeUrl } = require('./request-utils');
 const FetchMock = {};
 const { sanitizeRoute } = require('./compile-route');
@@ -7,9 +6,7 @@ const isName = nameOrMatcher =>
 	typeof nameOrMatcher === 'string' && /^[\da-zA-Z\-]+$/.test(nameOrMatcher);
 
 const filterCallsWithMatcher = (matcher, options = {}, calls) => {
-	debug('/** Begin generating synthetic matcher for inspecting **/')
-	matcher = generateMatcher(sanitizeRoute(Object.assign({ matcher }, options)));
-	debug('/** End generating synthetic matcher for inspecting **/')
+	matcher = generateMatcher(sanitizeRoute(Object.assign({ matcher }, options), false));
 	return calls.filter(([url, options]) => matcher(normalizeUrl(url), options));
 };
 

From e18b7ff2490bd5058818cdc7edf4c453d191f7d3 Mon Sep 17 00:00:00 2001
From: Rhys Evans <rhys.evans@ft.com>
Date: Sat, 27 Jul 2019 23:19:51 +0100
Subject: [PATCH 03/12] debug logs for fetch handler function

---
 src/lib/compile-route.js |  6 +++---
 src/lib/fetch-handler.js | 33 +++++++++++++++++++++++++++++----
 2 files changed, 32 insertions(+), 7 deletions(-)

diff --git a/src/lib/compile-route.js b/src/lib/compile-route.js
index 49702aae..caa49661 100644
--- a/src/lib/compile-route.js
+++ b/src/lib/compile-route.js
@@ -52,10 +52,10 @@ const sanitizeRoute = (route, useDebugger = true) => {
 	route.functionMatcher = route.matcher || route.functionMatcher;
 
 	useDebugger && debug('Setting route.identifier...')
-	useDebugger && debug(`- route.name is ${route.name}`)
-	useDebugger && debug(`- route.matcher is ${route.matcher}`)
+	useDebugger && debug(`  route.name is ${route.name}`)
+	useDebugger && debug(`  route.matcher is ${route.matcher}`)
 	route.identifier = route.name || route.url || route.functionMatcher;
-	useDebugger && debug(`=> route.identifier set to ${route.identifier}`);
+	useDebugger && debug(`  > route.identifier set to ${route.identifier}`);
 	return route;
 };
 
diff --git a/src/lib/fetch-handler.js b/src/lib/fetch-handler.js
index 971aef71..0ce7f0e0 100755
--- a/src/lib/fetch-handler.js
+++ b/src/lib/fetch-handler.js
@@ -1,3 +1,4 @@
+const debug = require('debug')('fetch-mock')
 const responseBuilder = require('./response-builder');
 const requestUtils = require('./request-utils');
 const FetchMock = {};
@@ -23,6 +24,7 @@ const resolve = async (
 	options,
 	request
 ) => {
+	debug('Recursively resolving function and promise responses')
 	// We want to allow things like
 	// - function returning a Promise for a response
 	// - delaying (using a timeout Promise) a function's execution to generate
@@ -32,22 +34,36 @@ const resolve = async (
 	// have something that looks like neither Promise nor function
 	while (true) {
 		if (typeof response === 'function') {
+			debug('  Response is a function')
 			// in the case of falling back to the network we need to make sure we're using
 			// the original Request instance, not our normalised url + options
-			response =
-				request && responseIsFetch
-					? response(request)
-					: response(url, options, request);
+			if (responseIsFetch) {
+				if (request) {
+					debug('  > Calling fetch with Request instance')
+					return response(request)
+				}
+				debug('  > Calling fetch with url and options')
+				return response(url, options);
+			} else {
+				debug('  > Calling custom matcher function')
+				return response(url, options, request);
+			}
 		} else if (typeof response.then === 'function') {
+			debug('  Response is a promise')
+			debug('  > Resolving promise')
 			response = await response;
 		} else {
+			debug('  Response is not a function or a promise')
+			debug('  > Returning response for conversion into Response instance')
 			return response;
 		}
 	}
 };
 
 FetchMock.fetchHandler = function(url, options, request) {
+	debug('**HANDLING NEW FETCH**');
 	const normalizedRequest = requestUtils.normalizeRequest(
+	({ url, options, request } = requestUtils.normalizeRequest(
 		url,
 		options,
 		this.config.Request
@@ -67,6 +83,7 @@ FetchMock.fetchHandler = function(url, options, request) {
 	// constructors defined by the user
 	return new this.config.Promise((res, rej) => {
 		if (signal) {
+			debug('options.signal exists - setting up fetch aborting')
 			const abort = () => {
 				// note that DOMException is not available in node.js; even node-fetch uses a custom error class: https://github.com/bitinn/node-fetch/blob/master/src/abort-error.js
 				rej(
@@ -77,6 +94,7 @@ FetchMock.fetchHandler = function(url, options, request) {
 				done();
 			};
 			if (signal.aborted) {
+				debug('options.signal is already aborted- abort the fetch')
 				abort();
 			}
 			signal.addEventListener('abort', abort);
@@ -91,13 +109,16 @@ FetchMock.fetchHandler = function(url, options, request) {
 FetchMock.fetchHandler.isMock = true;
 
 FetchMock.executeRouter = function(url, options, request) {
+	debug('Attempting to match request to defined routes')
 	if (this.config.fallbackToNetwork === 'always') {
+		debug('  Configured with fallbackToNetwork=always - passing through to fetch')
 		return { response: this.getNativeFetch(), responseIsFetch: true };
 	}
 
 	const match = this.router(url, options, request);
 
 	if (match) {
+		debug('  Matching route found')
 		return match;
 	}
 
@@ -108,6 +129,7 @@ FetchMock.executeRouter = function(url, options, request) {
 	this.push({ url, options, request, isUnmatched: true });
 
 	if (this.fallbackResponse) {
+		debug('  No matching route found - using fallbackResponse')
 		return { response: this.fallbackResponse };
 	}
 
@@ -119,6 +141,7 @@ FetchMock.executeRouter = function(url, options, request) {
 		);
 	}
 
+	debug('  Configured to fallbackToNetwork - passing through to fetch')
 	return { response: this.getNativeFetch(), responseIsFetch: true };
 };
 
@@ -128,11 +151,13 @@ FetchMock.generateResponse = async function(route, url, options, request) {
 	// If the response says to throw an error, throw it
 	// Type checking is to deal with sinon spies having a throws property :-0
 	if (response.throws && typeof response !== 'function') {
+		debug('response.throws is defined - throwing an error')
 		throw response.throws;
 	}
 
 	// If the response is a pre-made Response, respond with it
 	if (this.config.Response.prototype.isPrototypeOf(response)) {
+		debug('response is already a Response instance - returning it')
 		return response;
 	}
 

From 4fa4c69229f350fa474e6a98260b46c0816cb47d Mon Sep 17 00:00:00 2001
From: Rhys Evans <rhys.evans@ft.com>
Date: Sat, 27 Jul 2019 23:20:44 +0100
Subject: [PATCH 04/12] debug logs for fetch handler function

---
 src/lib/generate-matcher.js | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/lib/generate-matcher.js b/src/lib/generate-matcher.js
index baae61be..8e33ac42 100644
--- a/src/lib/generate-matcher.js
+++ b/src/lib/generate-matcher.js
@@ -1,3 +1,4 @@
+const debug = require('debug')('fetch-mock');
 const glob = require('glob-to-regexp');
 const pathToRegexp = require('path-to-regexp');
 const querystring = require('querystring');
@@ -133,6 +134,7 @@ const getUrlMatcher = route => {
 };
 
 module.exports = route => {
+	debug('Generating matcher for route')
 	const matchers = [
 		route.query && getQueryStringMatcher(route),
 		route.method && getMethodMatcher(route),

From c5f6c20c6d532068c2a543aec87fa3fbdc7a40f4 Mon Sep 17 00:00:00 2001
From: Rhys Evans <rhys.evans@ft.com>
Date: Sat, 27 Jul 2019 23:23:38 +0100
Subject: [PATCH 05/12] minor refactor to make debug logging easier in matcher
 building

---
 src/lib/generate-matcher.js | 30 +++++++++++++++++++++++++++---
 src/lib/inspecting.js       |  2 +-
 2 files changed, 28 insertions(+), 4 deletions(-)

diff --git a/src/lib/generate-matcher.js b/src/lib/generate-matcher.js
index 8e33ac42..2de2543a 100644
--- a/src/lib/generate-matcher.js
+++ b/src/lib/generate-matcher.js
@@ -25,6 +25,9 @@ const stringMatchers = {
 };
 
 const getHeaderMatcher = ({ headers: expectedHeaders }) => {
+	if (!expectedHeaders) {
+		return
+	}
 	const expectation = headerUtils.toLowerCase(expectedHeaders);
 	return (url, { headers = {} }) => {
 		const lowerCaseHeaders = headerUtils.toLowerCase(
@@ -38,11 +41,17 @@ const getHeaderMatcher = ({ headers: expectedHeaders }) => {
 };
 
 const getMethodMatcher = ({ method: expectedMethod }) => {
+	if (!expectedMethod) {
+		return
+	}
 	return (url, { method }) =>
 		expectedMethod === (method ? method.toLowerCase() : 'get');
 };
 
 const getQueryStringMatcher = ({ query: expectedQuery }) => {
+	if (!expectedQuery) {
+		return
+	}
 	const keys = Object.keys(expectedQuery);
 	return url => {
 		const query = querystring.parse(getQuery(url));
@@ -50,15 +59,18 @@ const getQueryStringMatcher = ({ query: expectedQuery }) => {
 	};
 };
 
-const getParamsMatcher = ({ params: expectedParams, url: matcheUrl }) => {
-	if (!/express:/.test(matcheUrl)) {
+const getParamsMatcher = ({ params: expectedParams, url: matcherUrl }) => {
+	if (!expectedParams) {
+		return
+	}
+	if (!/express:/.test(matcherUrl)) {
 		throw new Error(
 			'fetch-mock: matching on params is only possible when using an express: matcher'
 		);
 	}
 	const expectedKeys = Object.keys(expectedParams);
 	const keys = [];
-	const re = pathToRegexp(matcheUrl.replace(/^express:/, ''), keys);
+	const re = pathToRegexp(matcherUrl.replace(/^express:/, ''), keys);
 	return url => {
 		const vals = re.exec(getPath(url)) || [];
 		vals.shift();
@@ -106,6 +118,7 @@ const getFullUrlMatcher = (route, matcherUrl, query) => {
 	};
 };
 
+<<<<<<< HEAD
 const getFunctionMatcher = ({ functionMatcher }) => functionMatcher;
 
 const getUrlMatcher = route => {
@@ -143,6 +156,17 @@ module.exports = route => {
 		route.body && getBodyMatcher(route),
 		route.functionMatcher && getFunctionMatcher(route),
 		route.url && getUrlMatcher(route)
+=======
+module.exports = (route, useDebugger = true) => {
+	useDebugger && debug('Compiling matcher for route')
+	const matchers = [
+		getQueryStringMatcher(route),
+		getMethodMatcher(route),
+		getHeaderMatcher(route),
+		getParamsMatcher(route),
+		getFunctionMatcher(route),
+		getUrlMatcher(route)
+>>>>>>> minor refactor to make debug logging easier in matcher building
 	].filter(matcher => !!matcher);
 
 	return (url, options = {}, request) =>
diff --git a/src/lib/inspecting.js b/src/lib/inspecting.js
index 3e763829..e5d7dd59 100644
--- a/src/lib/inspecting.js
+++ b/src/lib/inspecting.js
@@ -6,7 +6,7 @@ const isName = nameOrMatcher =>
 	typeof nameOrMatcher === 'string' && /^[\da-zA-Z\-]+$/.test(nameOrMatcher);
 
 const filterCallsWithMatcher = (matcher, options = {}, calls) => {
-	matcher = generateMatcher(sanitizeRoute(Object.assign({ matcher }, options), false));
+	matcher = generateMatcher(sanitizeRoute(Object.assign({ matcher }, options), false), false);
 	return calls.filter(([url, options]) => matcher(normalizeUrl(url), options));
 };
 

From 959288f475eb7a64fc681e7bb58739a75acd0031 Mon Sep 17 00:00:00 2001
From: Rhys Evans <rhys.evans@ft.com>
Date: Sun, 28 Jul 2019 00:17:52 +0100
Subject: [PATCH 06/12] most matcher debug logs written

---
 src/lib/compile-route.js    |   6 +-
 src/lib/fetch-handler.js    |  38 ++++++------
 src/lib/generate-matcher.js | 112 +++++++++++++++++++++++++++---------
 src/lib/inspecting.js       |   5 +-
 4 files changed, 111 insertions(+), 50 deletions(-)

diff --git a/src/lib/compile-route.js b/src/lib/compile-route.js
index caa49661..50977b88 100644
--- a/src/lib/compile-route.js
+++ b/src/lib/compile-route.js
@@ -1,4 +1,4 @@
-const debug = require('debug')('fetch-mock')
+const debug = require('debug')('fetch-mock');
 const generateMatcher = require('./generate-matcher');
 
 const matcherProperties = [
@@ -74,11 +74,11 @@ const validateRoute = route => {
 const limitMatcher = route => {
 	debug('Limiting number of requests to handle by route');
 	if (!route.repeat) {
-		debug('No `repeat` value set on route. Will match any number of requests')
+		debug('No `repeat` value set on route. Will match any number of requests');
 		return;
 	}
 
-	debug(`Route set to repeat ${route.repeat} times`)
+	debug(`Route set to repeat ${route.repeat} times`);
 	const matcher = route.matcher;
 	let timesLeft = route.repeat;
 	route.matcher = (url, options) => {
diff --git a/src/lib/fetch-handler.js b/src/lib/fetch-handler.js
index 0ce7f0e0..d55c2315 100755
--- a/src/lib/fetch-handler.js
+++ b/src/lib/fetch-handler.js
@@ -1,4 +1,4 @@
-const debug = require('debug')('fetch-mock')
+const debug = require('debug')('fetch-mock');
 const responseBuilder = require('./response-builder');
 const requestUtils = require('./request-utils');
 const FetchMock = {};
@@ -24,7 +24,7 @@ const resolve = async (
 	options,
 	request
 ) => {
-	debug('Recursively resolving function and promise responses')
+	debug('Recursively resolving function and promise responses');
 	// We want to allow things like
 	// - function returning a Promise for a response
 	// - delaying (using a timeout Promise) a function's execution to generate
@@ -34,27 +34,27 @@ const resolve = async (
 	// have something that looks like neither Promise nor function
 	while (true) {
 		if (typeof response === 'function') {
-			debug('  Response is a function')
+			debug('  Response is a function');
 			// in the case of falling back to the network we need to make sure we're using
 			// the original Request instance, not our normalised url + options
 			if (responseIsFetch) {
 				if (request) {
-					debug('  > Calling fetch with Request instance')
-					return response(request)
+					debug('  > Calling fetch with Request instance');
+					return response(request);
 				}
-				debug('  > Calling fetch with url and options')
+				debug('  > Calling fetch with url and options');
 				return response(url, options);
 			} else {
-				debug('  > Calling custom matcher function')
+				debug('  > Calling custom matcher function');
 				return response(url, options, request);
 			}
 		} else if (typeof response.then === 'function') {
-			debug('  Response is a promise')
-			debug('  > Resolving promise')
+			debug('  Response is a promise');
+			debug('  > Resolving promise');
 			response = await response;
 		} else {
-			debug('  Response is not a function or a promise')
-			debug('  > Returning response for conversion into Response instance')
+			debug('  Response is not a function or a promise');
+			debug('  > Returning response for conversion into Response instance');
 			return response;
 		}
 	}
@@ -109,16 +109,18 @@ FetchMock.fetchHandler = function(url, options, request) {
 FetchMock.fetchHandler.isMock = true;
 
 FetchMock.executeRouter = function(url, options, request) {
-	debug('Attempting to match request to defined routes')
+	debug('Attempting to match request to defined routes');
 	if (this.config.fallbackToNetwork === 'always') {
-		debug('  Configured with fallbackToNetwork=always - passing through to fetch')
+		debug(
+			'  Configured with fallbackToNetwork=always - passing through to fetch'
+		);
 		return { response: this.getNativeFetch(), responseIsFetch: true };
 	}
 
 	const match = this.router(url, options, request);
 
 	if (match) {
-		debug('  Matching route found')
+		debug('  Matching route found');
 		return match;
 	}
 
@@ -129,7 +131,7 @@ FetchMock.executeRouter = function(url, options, request) {
 	this.push({ url, options, request, isUnmatched: true });
 
 	if (this.fallbackResponse) {
-		debug('  No matching route found - using fallbackResponse')
+		debug('  No matching route found - using fallbackResponse');
 		return { response: this.fallbackResponse };
 	}
 
@@ -141,7 +143,7 @@ FetchMock.executeRouter = function(url, options, request) {
 		);
 	}
 
-	debug('  Configured to fallbackToNetwork - passing through to fetch')
+	debug('  Configured to fallbackToNetwork - passing through to fetch');
 	return { response: this.getNativeFetch(), responseIsFetch: true };
 };
 
@@ -151,13 +153,13 @@ FetchMock.generateResponse = async function(route, url, options, request) {
 	// If the response says to throw an error, throw it
 	// Type checking is to deal with sinon spies having a throws property :-0
 	if (response.throws && typeof response !== 'function') {
-		debug('response.throws is defined - throwing an error')
+		debug('response.throws is defined - throwing an error');
 		throw response.throws;
 	}
 
 	// If the response is a pre-made Response, respond with it
 	if (this.config.Response.prototype.isPrototypeOf(response)) {
-		debug('response is already a Response instance - returning it')
+		debug('response is already a Response instance - returning it');
 		return response;
 	}
 
diff --git a/src/lib/generate-matcher.js b/src/lib/generate-matcher.js
index 2de2543a..1e351375 100644
--- a/src/lib/generate-matcher.js
+++ b/src/lib/generate-matcher.js
@@ -10,30 +10,42 @@ const {
 } = require('./request-utils');
 const isEqual = require('lodash.isequal');
 
+const debuggableUrlFunc = func => url => {
+	debug('Actual url:', url);
+	return func(url);
+};
+
 const stringMatchers = {
-	begin: targetString => url => url.indexOf(targetString) === 0,
-	end: targetString => url => url.substr(-targetString.length) === targetString,
+	begin: targetString =>
+		debuggableUrlFunc(url => url.indexOf(targetString) === 0),
+	end: targetString =>
+		debuggableUrlFunc(url => url.substr(-targetString.length) === targetString),
 	glob: targetString => {
 		const urlRX = glob(targetString);
-		return url => urlRX.test(url);
+		return debuggableUrlFunc(url => urlRX.test(url));
 	},
 	express: targetString => {
 		const urlRX = pathToRegexp(targetString);
-		return url => urlRX.test(getPath(url));
+		return debuggableUrlFunc(url => urlRX.test(getPath(url)));
 	},
-	path: targetString => url => getPath(url) === targetString
+	path: targetString => debuggableUrlFunc(url => getPath(url) === targetString)
 };
 
 const getHeaderMatcher = ({ headers: expectedHeaders }) => {
+	debug('Generating header matcher');
 	if (!expectedHeaders) {
-		return
+		debug('  No header expectations defined - skipping');
+		return;
 	}
 	const expectation = headerUtils.toLowerCase(expectedHeaders);
+	debug('  Expected headers:', expectation);
 	return (url, { headers = {} }) => {
+		debug('Attempting to match headers');
 		const lowerCaseHeaders = headerUtils.toLowerCase(
 			headerUtils.normalize(headers)
 		);
-
+		debug('  Expected headers:', expectation);
+		debug('  Actual headers:', lowerCaseHeaders);
 		return Object.keys(expectation).every(headerName =>
 			headerUtils.equal(lowerCaseHeaders[headerName], expectation[headerName])
 		);
@@ -41,37 +53,55 @@ const getHeaderMatcher = ({ headers: expectedHeaders }) => {
 };
 
 const getMethodMatcher = ({ method: expectedMethod }) => {
+	debug('Generating method matcher');
 	if (!expectedMethod) {
-		return
+		debug('  No method expectations defined - skipping');
+		return;
 	}
-	return (url, { method }) =>
-		expectedMethod === (method ? method.toLowerCase() : 'get');
+	debug('  Expected method:', expectedMethod);
+	return (url, { method }) => {
+		debug('Attempting to match method');
+		const actualMethod = method ? method.toLowerCase() : 'get';
+		debug('  Expected method:', expectedMethod);
+		debug('  Actual method:', actualMethod);
+		return expectedMethod === actualMethod;
+	};
 };
 
 const getQueryStringMatcher = ({ query: expectedQuery }) => {
+	debug('Generating query parameters matcher');
 	if (!expectedQuery) {
-		return
+		debug('  No query parameters expectations defined - skipping');
+		return;
 	}
+	debug('  Expected query parameters:', expectedQuery);
 	const keys = Object.keys(expectedQuery);
 	return url => {
+		debug('Attempting to match query parameters');
 		const query = querystring.parse(getQuery(url));
+		debug('  Expected query parameters:', expectedQuery);
+		debug('  Actual query parameters:', query);
 		return keys.every(key => query[key] === expectedQuery[key]);
 	};
 };
 
 const getParamsMatcher = ({ params: expectedParams, url: matcherUrl }) => {
+	debug('Generating path parameters matcher');
 	if (!expectedParams) {
-		return
+		debug('  No path parameters expectations defined - skipping');
+		return;
 	}
 	if (!/express:/.test(matcherUrl)) {
 		throw new Error(
 			'fetch-mock: matching on params is only possible when using an express: matcher'
 		);
 	}
+	debug('  Expected path parameters:', expectedParams);
 	const expectedKeys = Object.keys(expectedParams);
 	const keys = [];
 	const re = pathToRegexp(matcherUrl.replace(/^express:/, ''), keys);
 	return url => {
+		debug('Attempting to match path parameters');
 		const vals = re.exec(getPath(url)) || [];
 		vals.shift();
 		const params = keys.reduce(
@@ -79,13 +109,18 @@ const getParamsMatcher = ({ params: expectedParams, url: matcherUrl }) => {
 				vals[i] ? Object.assign(map, { [name]: vals[i] }) : map,
 			{}
 		);
+		debug('  Expected path parameters:', expectedParams);
+		debug('  Actual path parameters:', params);
 		return expectedKeys.every(key => params[key] === expectedParams[key]);
 	};
 };
 
 const getBodyMatcher = ({ body: expectedBody }) => {
+	debug('Generating body matcher');
 	return (url, { body, method = 'get' }) => {
+		debug('Attempting to match body');
 		if (method.toLowerCase() === 'get') {
+			debug('  GET request - skip matching body');
 			// GET requests don’t send a body so the body matcher should be ignored for them
 			return true;
 		}
@@ -93,8 +128,13 @@ const getBodyMatcher = ({ body: expectedBody }) => {
 		let sentBody;
 
 		try {
+			debug('  Parsing request body as JSON');
 			sentBody = JSON.parse(body);
-		} catch (_) {}
+		} catch (err) {
+			debug('  Failed to parse request body as JSON', err);
+		}
+		debug('Expected body:', expectedBody);
+		debug('Actual body:', sentBody);
 
 		return sentBody && isEqual(sentBody, expectedBody);
 	};
@@ -105,39 +145,66 @@ const getFullUrlMatcher = (route, matcherUrl, query) => {
 	// but we have to be careful to normalize the url we check and the name
 	// of the route to allow for e.g. http://it.at.there being indistinguishable
 	// from http://it.at.there/ once we start generating Request/Url objects
+	debug('  Matching using full url', matcherUrl);
 	const expectedUrl = normalizeUrl(matcherUrl);
+	debug('  Normalised url to:', matcherUrl);
 	if (route.identifier === matcherUrl) {
+		debug('  Updating route identifier to match normalized url:', matcherUrl);
 		route.identifier = expectedUrl;
 	}
 
 	return matcherUrl => {
+		debug('Expected url:', expectedUrl);
+		debug('Actual url:', matcherUrl);
 		if (query && expectedUrl.indexOf('?')) {
+			debug('Ignoring query string when matching url');
 			return matcherUrl.indexOf(expectedUrl) === 0;
 		}
 		return normalizeUrl(matcherUrl) === expectedUrl;
 	};
 };
 
-<<<<<<< HEAD
-const getFunctionMatcher = ({ functionMatcher }) => functionMatcher;
+const getFunctionMatcher = ({ matcher, functionMatcher }) => {
+	if (functionMatcher) {
+		debug('Using user defined function as matcher alongside other matchers');
+		return functionMatcher;
+	}
+	if (typeof matcher === 'function') {
+		debug('Using user defined function as matcher');
+		return matcher;
+	}
+};
+
+const getFunctionMatcher = ({ functionMatcher }) => {
+	debug('Detected user defined function matcher', functionMatcher);
+	return (...args) => {
+		debug('Calling function matcher with arguments', args)
+		return functionMatcher(...args);
+	}
+}
 
 const getUrlMatcher = route => {
+	debug('Generating url matcher');
 	const { url: matcherUrl, query } = route;
 
 	if (matcherUrl === '*') {
+		debug('  Using universal * rule to match any url');
 		return () => true;
 	}
 
 	if (matcherUrl instanceof RegExp) {
+		debug('  Using regular expression to match url:', matcherUrl);
 		return url => matcherUrl.test(url);
 	}
 
 	if (matcherUrl.href) {
+		debug(`  Using URL object to match url`, matcherUrl);
 		return getFullUrlMatcher(route, matcherUrl.href, query);
 	}
 
 	for (const shorthand in stringMatchers) {
 		if (matcherUrl.indexOf(shorthand + ':') === 0) {
+			debug(`  Using ${shorthand}: pattern to match url`, matcherUrl);
 			const urlFragment = matcherUrl.replace(new RegExp(`^${shorthand}:`), '');
 			return stringMatchers[shorthand](urlFragment);
 		}
@@ -146,8 +213,8 @@ const getUrlMatcher = route => {
 	return getFullUrlMatcher(route, matcherUrl, query);
 };
 
-module.exports = route => {
-	debug('Generating matcher for route')
+module.exports = (route, useDebugger = true) => {
+	useDebugger && debug('Compiling matcher for route');
 	const matchers = [
 		route.query && getQueryStringMatcher(route),
 		route.method && getMethodMatcher(route),
@@ -156,17 +223,6 @@ module.exports = route => {
 		route.body && getBodyMatcher(route),
 		route.functionMatcher && getFunctionMatcher(route),
 		route.url && getUrlMatcher(route)
-=======
-module.exports = (route, useDebugger = true) => {
-	useDebugger && debug('Compiling matcher for route')
-	const matchers = [
-		getQueryStringMatcher(route),
-		getMethodMatcher(route),
-		getHeaderMatcher(route),
-		getParamsMatcher(route),
-		getFunctionMatcher(route),
-		getUrlMatcher(route)
->>>>>>> minor refactor to make debug logging easier in matcher building
 	].filter(matcher => !!matcher);
 
 	return (url, options = {}, request) =>
diff --git a/src/lib/inspecting.js b/src/lib/inspecting.js
index e5d7dd59..8a5e6fbe 100644
--- a/src/lib/inspecting.js
+++ b/src/lib/inspecting.js
@@ -6,7 +6,10 @@ const isName = nameOrMatcher =>
 	typeof nameOrMatcher === 'string' && /^[\da-zA-Z\-]+$/.test(nameOrMatcher);
 
 const filterCallsWithMatcher = (matcher, options = {}, calls) => {
-	matcher = generateMatcher(sanitizeRoute(Object.assign({ matcher }, options), false), false);
+	matcher = generateMatcher(
+		sanitizeRoute(Object.assign({ matcher }, options), false),
+		false
+	);
 	return calls.filter(([url, options]) => matcher(normalizeUrl(url), options));
 };
 

From 13b947570d7288e29d762b0bf42b9c79b417a115 Mon Sep 17 00:00:00 2001
From: Rhys Evans <rhys.evans@ft.com>
Date: Sat, 25 Jan 2020 17:37:18 +0000
Subject: [PATCH 07/12] more debug logs

---
 README.md                       |  2 +-
 src/lib/compile-route.js        | 27 +++++++++++++++++----------
 src/lib/fetch-handler.js        | 24 +++++++++++++++---------
 src/lib/generate-matcher.js     | 21 +++++----------------
 src/lib/inspecting.js           |  5 +----
 src/lib/set-up-and-tear-down.js | 10 +++++++++-
 6 files changed, 48 insertions(+), 41 deletions(-)

diff --git a/README.md b/README.md
index d14597cb..df202ecd 100644
--- a/README.md
+++ b/README.md
@@ -2,7 +2,7 @@
 
 Mock http requests made using [fetch](https://developer.mozilla.org/en-US/docs/Web/API/WindowOrWorkerGlobalScope/fetch).
 
-*New* If using jest, try the new [fetch-mock-jest](https://www.npmjs.com/package/fetch-mock-jest) wrapper.
+_New_ If using jest, try the new [fetch-mock-jest](https://www.npmjs.com/package/fetch-mock-jest) wrapper.
 
 ![node version](https://img.shields.io/node/v/fetch-mock.svg?style=flat-square)
 [![licence](https://img.shields.io/npm/l/fetch-mock.svg?style=flat-square)](https://github.com/wheresrhys/fetch-mock/blob/master/LICENSE)
diff --git a/src/lib/compile-route.js b/src/lib/compile-route.js
index 50977b88..298e9377 100644
--- a/src/lib/compile-route.js
+++ b/src/lib/compile-route.js
@@ -36,12 +36,12 @@ const argsToRoute = args => {
 	return routeConfig;
 };
 
-const sanitizeRoute = (route, useDebugger = true) => {
-	useDebugger && debug('Sanitizing route properties');
+const sanitizeRoute = route => {
+	debug('Sanitizing route properties');
 	route = Object.assign({}, route);
 
 	if (route.method) {
-		useDebugger && debug(`Converting method ${route.method} to lower case`);
+		debug(`Converting method ${route.method} to lower case`);
 		route.method = route.method.toLowerCase();
 	}
 	if (isUrlMatcher(route.matcher)) {
@@ -51,11 +51,12 @@ const sanitizeRoute = (route, useDebugger = true) => {
 
 	route.functionMatcher = route.matcher || route.functionMatcher;
 
-	useDebugger && debug('Setting route.identifier...')
-	useDebugger && debug(`  route.name is ${route.name}`)
-	useDebugger && debug(`  route.matcher is ${route.matcher}`)
+	debug('Setting route.identifier...');
+	debug(`  route.name is ${route.name}`);
+	debug(`  route.url is ${route.url}`);
+	debug(`  route.functionMatcher is ${route.functionMatcher}`);
 	route.identifier = route.name || route.url || route.functionMatcher;
-	useDebugger && debug(`  > route.identifier set to ${route.identifier}`);
+	debug(`  > route.identifier set to ${route.identifier}`);
 	return route;
 };
 
@@ -74,7 +75,7 @@ const validateRoute = route => {
 const limitMatcher = route => {
 	debug('Limiting number of requests to handle by route');
 	if (!route.repeat) {
-		debug('No `repeat` value set on route. Will match any number of requests');
+		debug('  No `repeat` value set on route. Will match any number of requests');
 		return;
 	}
 
@@ -92,11 +93,17 @@ const limitMatcher = route => {
 };
 
 const delayResponse = route => {
+	debug(`Delaying response`)
 	const { delay } = route;
 	if (delay) {
+		debug(`  Wrapping response in delay of ${delay} miliseconds`)
 		const response = route.response;
-		route.response = () =>
-			new Promise(res => setTimeout(() => res(response), delay));
+		route.response = () => {
+			debug(`Delaying response by ${delay} miliseconds`)
+			return new Promise(res => setTimeout(() => res(response), delay));
+		}
+	} else {
+		debug(`  No delay set on route. Will respond 'immediately' (but asynchronously)`)
 	}
 };
 
diff --git a/src/lib/fetch-handler.js b/src/lib/fetch-handler.js
index d55c2315..dbda73ab 100755
--- a/src/lib/fetch-handler.js
+++ b/src/lib/fetch-handler.js
@@ -45,8 +45,8 @@ const resolve = async (
 				debug('  > Calling fetch with url and options');
 				return response(url, options);
 			} else {
-				debug('  > Calling custom matcher function');
-				return response(url, options, request);
+				debug('  > Calling response function');
+				response = response(url, options, request);
 			}
 		} else if (typeof response.then === 'function') {
 			debug('  Response is a promise');
@@ -61,9 +61,8 @@ const resolve = async (
 };
 
 FetchMock.fetchHandler = function(url, options, request) {
-	debug('**HANDLING NEW FETCH**');
+	debug('fetch called with:', url, options)
 	const normalizedRequest = requestUtils.normalizeRequest(
-	({ url, options, request } = requestUtils.normalizeRequest(
 		url,
 		options,
 		this.config.Request
@@ -83,7 +82,7 @@ FetchMock.fetchHandler = function(url, options, request) {
 	// constructors defined by the user
 	return new this.config.Promise((res, rej) => {
 		if (signal) {
-			debug('options.signal exists - setting up fetch aborting')
+			debug('options.signal exists - setting up fetch aborting');
 			const abort = () => {
 				// note that DOMException is not available in node.js; even node-fetch uses a custom error class: https://github.com/bitinn/node-fetch/blob/master/src/abort-error.js
 				rej(
@@ -94,7 +93,7 @@ FetchMock.fetchHandler = function(url, options, request) {
 				done();
 			};
 			if (signal.aborted) {
-				debug('options.signal is already aborted- abort the fetch')
+				debug('options.signal is already aborted- abort the fetch');
 				abort();
 			}
 			signal.addEventListener('abort', abort);
@@ -102,14 +101,18 @@ FetchMock.fetchHandler = function(url, options, request) {
 
 		this.generateResponse(route, url, options, request)
 			.then(res, rej)
-			.then(done, done);
+			.then(done, done)
+			.then(() => {
+				debug('fetch handled successfully')
+				debug('---------------')
+			})
 	});
 };
 
 FetchMock.fetchHandler.isMock = true;
 
 FetchMock.executeRouter = function(url, options, request) {
-	debug('Attempting to match request to defined routes');
+	debug(`Attempting to match request to a route`);
 	if (this.config.fallbackToNetwork === 'always') {
 		debug(
 			'  Configured with fallbackToNetwork=always - passing through to fetch'
@@ -173,7 +176,10 @@ FetchMock.generateResponse = async function(route, url, options, request) {
 };
 
 FetchMock.router = function(url, options, request) {
-	const route = this.routes.find(route => route.matcher(url, options, request));
+	const route = this.routes.find((route, i) => {
+		debug(`Trying to match route ${i}`)
+		return route.matcher(url, options, request)
+			});
 
 	if (route) {
 		this.push({
diff --git a/src/lib/generate-matcher.js b/src/lib/generate-matcher.js
index 1e351375..180a11df 100644
--- a/src/lib/generate-matcher.js
+++ b/src/lib/generate-matcher.js
@@ -164,24 +164,13 @@ const getFullUrlMatcher = (route, matcherUrl, query) => {
 	};
 };
 
-const getFunctionMatcher = ({ matcher, functionMatcher }) => {
-	if (functionMatcher) {
-		debug('Using user defined function as matcher alongside other matchers');
-		return functionMatcher;
-	}
-	if (typeof matcher === 'function') {
-		debug('Using user defined function as matcher');
-		return matcher;
-	}
-};
-
 const getFunctionMatcher = ({ functionMatcher }) => {
 	debug('Detected user defined function matcher', functionMatcher);
 	return (...args) => {
-		debug('Calling function matcher with arguments', args)
+		debug('Calling function matcher with arguments', args);
 		return functionMatcher(...args);
-	}
-}
+	};
+};
 
 const getUrlMatcher = route => {
 	debug('Generating url matcher');
@@ -213,8 +202,8 @@ const getUrlMatcher = route => {
 	return getFullUrlMatcher(route, matcherUrl, query);
 };
 
-module.exports = (route, useDebugger = true) => {
-	useDebugger && debug('Compiling matcher for route');
+module.exports = route => {
+	debug('Compiling matcher for route');
 	const matchers = [
 		route.query && getQueryStringMatcher(route),
 		route.method && getMethodMatcher(route),
diff --git a/src/lib/inspecting.js b/src/lib/inspecting.js
index 8a5e6fbe..65baed9c 100644
--- a/src/lib/inspecting.js
+++ b/src/lib/inspecting.js
@@ -6,10 +6,7 @@ const isName = nameOrMatcher =>
 	typeof nameOrMatcher === 'string' && /^[\da-zA-Z\-]+$/.test(nameOrMatcher);
 
 const filterCallsWithMatcher = (matcher, options = {}, calls) => {
-	matcher = generateMatcher(
-		sanitizeRoute(Object.assign({ matcher }, options), false),
-		false
-	);
+	matcher = generateMatcher(sanitizeRoute(Object.assign({ matcher }, options)));
 	return calls.filter(([url, options]) => matcher(normalizeUrl(url), options));
 };
 
diff --git a/src/lib/set-up-and-tear-down.js b/src/lib/set-up-and-tear-down.js
index d880ffb5..9c010d9c 100644
--- a/src/lib/set-up-and-tear-down.js
+++ b/src/lib/set-up-and-tear-down.js
@@ -1,3 +1,4 @@
+const debug = require('debug')('fetch-mock');
 const { compileRoute } = require('./compile-route');
 const FetchMock = {};
 
@@ -10,6 +11,7 @@ FetchMock.mock = function(...args) {
 };
 
 FetchMock.addRoute = function(uncompiledRoute) {
+	debug('Adding route', uncompiledRoute)
 	const route = this.compileRoute(uncompiledRoute);
 	const clashes = this.routes.filter(
 		({ identifier, method }) =>
@@ -24,6 +26,8 @@ FetchMock.addRoute = function(uncompiledRoute) {
 
 	if (overwriteRoutes === false || !clashes.length) {
 		this._uncompiledRoutes.push(uncompiledRoute);
+		debug('Route added successfully')
+		debug('---------------')
 		return this.routes.push(route);
 	}
 
@@ -33,7 +37,8 @@ FetchMock.addRoute = function(uncompiledRoute) {
 			this._uncompiledRoutes.splice(index, 1, uncompiledRoute);
 			this.routes.splice(index, 1, route);
 		});
-
+		debug('Route added successfully')
+		debug('---------------')
 		return this.routes;
 	}
 
@@ -45,6 +50,9 @@ FetchMock.addRoute = function(uncompiledRoute) {
 
 	this._uncompiledRoutes.push(uncompiledRoute);
 	this.routes.push(route);
+	debug('Route added successfully')
+	debug('---------------')
+
 };
 
 FetchMock._mock = function() {

From 51a7d6094c9da357a9f9d7b010c42b76b245ba3b Mon Sep 17 00:00:00 2001
From: Rhys Evans <rhys.evans@ft.com>
Date: Sat, 25 Jan 2020 21:14:13 +0000
Subject: [PATCH 08/12] most debug messages are done

---
 src/lib/compile-route.js        | 12 ++--
 src/lib/debug.js                | 24 ++++++++
 src/lib/fetch-handler.js        | 30 ++++++----
 src/lib/generate-matcher.js     |  3 +-
 src/lib/index.js                |  3 +
 src/lib/inspecting.js           | 99 +++++++++++++++++++++++++--------
 src/lib/request-utils.js        |  1 +
 src/lib/response-builder.js     |  1 +
 src/lib/set-up-and-tear-down.js | 10 +---
 9 files changed, 136 insertions(+), 47 deletions(-)
 create mode 100644 src/lib/debug.js

diff --git a/src/lib/compile-route.js b/src/lib/compile-route.js
index 298e9377..630deec2 100644
--- a/src/lib/compile-route.js
+++ b/src/lib/compile-route.js
@@ -1,4 +1,4 @@
-const debug = require('debug')('fetch-mock');
+const {debug, setDebugNamespace} = require('./debug');
 const generateMatcher = require('./generate-matcher');
 
 const matcherProperties = [
@@ -15,6 +15,7 @@ const isUrlMatcher = matcher =>
 	matcher instanceof RegExp ||
 	typeof matcher === 'string' ||
 	(typeof matcher === 'object' && 'href' in matcher);
+
 const isFunctionMatcher = matcher => typeof matcher === 'function';
 
 const argsToRoute = args => {
@@ -45,6 +46,7 @@ const sanitizeRoute = route => {
 		route.method = route.method.toLowerCase();
 	}
 	if (isUrlMatcher(route.matcher)) {
+		debug('Mock uses a url matcher', route.matcher)
 		route.url = route.matcher;
 		delete route.matcher;
 	}
@@ -56,7 +58,7 @@ const sanitizeRoute = route => {
 	debug(`  route.url is ${route.url}`);
 	debug(`  route.functionMatcher is ${route.functionMatcher}`);
 	route.identifier = route.name || route.url || route.functionMatcher;
-	debug(`  > route.identifier set to ${route.identifier}`);
+	debug(`  -> route.identifier set to ${route.identifier}`);
 	return route;
 };
 
@@ -79,7 +81,7 @@ const limitMatcher = route => {
 		return;
 	}
 
-	debug(`Route set to repeat ${route.repeat} times`);
+	debug(`  Route set to repeat ${route.repeat} times`);
 	const matcher = route.matcher;
 	let timesLeft = route.repeat;
 	route.matcher = (url, options) => {
@@ -93,7 +95,7 @@ const limitMatcher = route => {
 };
 
 const delayResponse = route => {
-	debug(`Delaying response`)
+	debug(`Applying response delay settings`)
 	const { delay } = route;
 	if (delay) {
 		debug(`  Wrapping response in delay of ${delay} miliseconds`)
@@ -108,12 +110,14 @@ const delayResponse = route => {
 };
 
 const compileRoute = function(args) {
+	setDebugNamespace('compile');
 	debug('Compiling route');
 	const route = sanitizeRoute(argsToRoute(args));
 	validateRoute(route);
 	route.matcher = generateMatcher(route);
 	limitMatcher(route);
 	delayResponse(route);
+	setDebugNamespace();
 	return route;
 };
 
diff --git a/src/lib/debug.js b/src/lib/debug.js
new file mode 100644
index 00000000..4f4db385
--- /dev/null
+++ b/src/lib/debug.js
@@ -0,0 +1,24 @@
+const debug = require('debug');
+
+let debugFunc
+let phase = 'default';
+let namespace = '';
+const newDebug = () => {
+	debugFunc = namespace ? debug(`fetch-mock:${phase}:${namespace}`) : debug(`fetch-mock:${phase}`)
+}
+
+newDebug()
+
+module.exports = {
+	debug: (...args) => {
+		debugFunc(...args)
+	},
+	setDebugNamespace: str => {
+		namespace = str
+		newDebug();
+	},
+	setDebugPhase: str => {
+		phase = str || 'default';
+		newDebug();
+	}
+}
diff --git a/src/lib/fetch-handler.js b/src/lib/fetch-handler.js
index dbda73ab..f566e32d 100755
--- a/src/lib/fetch-handler.js
+++ b/src/lib/fetch-handler.js
@@ -1,4 +1,4 @@
-const debug = require('debug')('fetch-mock');
+const {debug, setDebugPhase} = require('./debug');
 const responseBuilder = require('./response-builder');
 const requestUtils = require('./request-utils');
 const FetchMock = {};
@@ -39,28 +39,29 @@ const resolve = async (
 			// the original Request instance, not our normalised url + options
 			if (responseIsFetch) {
 				if (request) {
-					debug('  > Calling fetch with Request instance');
+					debug('  -> Calling fetch with Request instance');
 					return response(request);
 				}
-				debug('  > Calling fetch with url and options');
+				debug('  -> Calling fetch with url and options');
 				return response(url, options);
 			} else {
-				debug('  > Calling response function');
+				debug('  -> Calling response function');
 				response = response(url, options, request);
 			}
 		} else if (typeof response.then === 'function') {
 			debug('  Response is a promise');
-			debug('  > Resolving promise');
+			debug('  -> Resolving promise');
 			response = await response;
 		} else {
 			debug('  Response is not a function or a promise');
-			debug('  > Returning response for conversion into Response instance');
+			debug('  -> Exiting response resolution recursion');
 			return response;
 		}
 	}
 };
 
 FetchMock.fetchHandler = function(url, options, request) {
+	setDebugPhase('handle');
 	debug('fetch called with:', url, options)
 	const normalizedRequest = requestUtils.normalizeRequest(
 		url,
@@ -72,6 +73,12 @@ FetchMock.fetchHandler = function(url, options, request) {
 
 	const { signal } = normalizedRequest;
 
+	debug('Request normalised')
+	debug('  url', url)
+	debug('  options', options)
+	debug('  request', request)
+	debug('  signal', signal)
+
 	const route = this.executeRouter(url, options, request);
 
 	// this is used to power the .flush() method
@@ -82,8 +89,9 @@ FetchMock.fetchHandler = function(url, options, request) {
 	// constructors defined by the user
 	return new this.config.Promise((res, rej) => {
 		if (signal) {
-			debug('options.signal exists - setting up fetch aborting');
+			debug('signal exists - enabling fetch abort');
 			const abort = () => {
+				debug('aborting fetch');
 				// note that DOMException is not available in node.js; even node-fetch uses a custom error class: https://github.com/bitinn/node-fetch/blob/master/src/abort-error.js
 				rej(
 					typeof DOMException !== 'undefined'
@@ -93,7 +101,7 @@ FetchMock.fetchHandler = function(url, options, request) {
 				done();
 			};
 			if (signal.aborted) {
-				debug('options.signal is already aborted- abort the fetch');
+				debug('signal is already aborted - aborting the fetch');
 				abort();
 			}
 			signal.addEventListener('abort', abort);
@@ -103,8 +111,7 @@ FetchMock.fetchHandler = function(url, options, request) {
 			.then(res, rej)
 			.then(done, done)
 			.then(() => {
-				debug('fetch handled successfully')
-				debug('---------------')
+				setDebugPhase();
 			})
 	});
 };
@@ -196,13 +203,14 @@ FetchMock.getNativeFetch = function() {
 	const func = this.realFetch || (this.isSandbox && this.config.fetch);
 	if (!func) {
 		throw new Error(
-			'fetch-mock: Falling back to network only available on gloabl fetch-mock, or by setting config.fetch on sandboxed fetch-mock'
+			'fetch-mock: Falling back to network only available on global fetch-mock, or by setting config.fetch on sandboxed fetch-mock'
 		);
 	}
 	return func;
 };
 
 FetchMock.push = function({ url, options, request, isUnmatched, identifier }) {
+	debug('Recording fetch call', { url, options, request, isUnmatched, identifier })
 	const args = [url, options];
 	args.request = request;
 	args.identifier = identifier;
diff --git a/src/lib/generate-matcher.js b/src/lib/generate-matcher.js
index 180a11df..caef1d0a 100644
--- a/src/lib/generate-matcher.js
+++ b/src/lib/generate-matcher.js
@@ -1,4 +1,4 @@
-const debug = require('debug')('fetch-mock');
+const {debug} = require('./debug');
 const glob = require('glob-to-regexp');
 const pathToRegexp = require('path-to-regexp');
 const querystring = require('querystring');
@@ -214,6 +214,7 @@ module.exports = route => {
 		route.url && getUrlMatcher(route)
 	].filter(matcher => !!matcher);
 
+	debug('Compiled matcher for route');
 	return (url, options = {}, request) =>
 		matchers.every(matcher => matcher(url, options, request));
 };
diff --git a/src/lib/index.js b/src/lib/index.js
index 44153747..601e8c87 100644
--- a/src/lib/index.js
+++ b/src/lib/index.js
@@ -1,3 +1,4 @@
+const {debug} = require('./debug');
 const setUpAndTearDown = require('./set-up-and-tear-down');
 const fetchHandler = require('./fetch-handler');
 const inspecting = require('./inspecting');
@@ -13,6 +14,7 @@ FetchMock.config = {
 };
 
 FetchMock.createInstance = function() {
+	debug('Creating fetch-mock instance')
 	const instance = Object.create(FetchMock);
 	instance._uncompiledRoutes = (this._uncompiledRoutes || []).slice();
 	instance.routes = instance._uncompiledRoutes.map(config =>
@@ -34,6 +36,7 @@ FetchMock.bindMethods = function() {
 };
 
 FetchMock.sandbox = function() {
+	debug('Creating sandboxed fetch-mock instance')
 	// this construct allows us to create a fetch-mock instance which is also
 	// a callable function, while circumventing circularity when defining the
 	// object that this function should be bound to
diff --git a/src/lib/inspecting.js b/src/lib/inspecting.js
index 65baed9c..3ab95a2a 100644
--- a/src/lib/inspecting.js
+++ b/src/lib/inspecting.js
@@ -1,3 +1,4 @@
+const {setDebugPhase, setDebugNamespace, debug} = require('./debug');
 const { normalizeUrl } = require('./request-utils');
 const FetchMock = {};
 const { sanitizeRoute } = require('./compile-route');
@@ -10,76 +11,118 @@ const filterCallsWithMatcher = (matcher, options = {}, calls) => {
 	return calls.filter(([url, options]) => matcher(normalizeUrl(url), options));
 };
 
+const formatDebug = (func) => {
+	return function (...args) {
+		setDebugPhase('inspect')
+		const result = func.call(this, ...args);
+		setDebugPhase()
+		return result;
+	}
+}
+
 FetchMock.filterCalls = function(nameOrMatcher, options) {
+	debug('Filtering fetch calls')
 	let calls = this._calls;
 	let matcher = '*';
 
 	if ([true, 'matched'].includes(nameOrMatcher)) {
+		debug(`Filter provided is ${nameOrMatcher}. Returning matched calls only`)
 		calls = calls.filter(({ isUnmatched }) => !isUnmatched);
+
 	} else if ([false, 'unmatched'].includes(nameOrMatcher)) {
+		debug(`Filter provided is ${nameOrMatcher}. Returning unmatched calls only`)
 		calls = calls.filter(({ isUnmatched }) => isUnmatched);
 	} else if (typeof nameOrMatcher === 'undefined') {
+		debug(`Filter provided is undefined. Returning all calls`)
 		calls = calls;
 	} else if (isName(nameOrMatcher)) {
+		debug(`Filter provided, looks like the name of a named route. Returning only calls handled by that route`)
 		calls = calls.filter(({ identifier }) => identifier === nameOrMatcher);
 	} else {
 		matcher = normalizeUrl(nameOrMatcher);
 		if (this.routes.some(({ identifier }) => identifier === matcher)) {
+			debug(`Filter provided, ${nameOrMatcher}, identifies a route. Returning only calls handled by that route`)
 			calls = calls.filter(call => call.identifier === matcher);
 		}
 	}
 
+
 	if ((options || matcher !== '*') && calls.length) {
 		if (typeof options === 'string') {
 			options = { method: options };
 		}
+		debug('Compiling filter and options to route in order to filter all calls', nameOrMatcher)
 		calls = filterCallsWithMatcher(matcher, options, calls);
 	}
+	debug(`Retrieved ${calls.length} calls`)
 	return calls;
 };
 
-FetchMock.calls = function(nameOrMatcher, options) {
+FetchMock.calls = formatDebug(function(nameOrMatcher, options) {
+	debug('retrieving matching calls');
 	return this.filterCalls(nameOrMatcher, options);
-};
+});
 
-FetchMock.lastCall = function(nameOrMatcher, options) {
+FetchMock.lastCall = formatDebug(function(nameOrMatcher, options) {
+	debug('retrieving last matching call');
 	return [...this.filterCalls(nameOrMatcher, options)].pop();
-};
+});
 
-FetchMock.lastUrl = function(nameOrMatcher, options) {
+FetchMock.lastUrl = formatDebug(function(nameOrMatcher, options) {
+	debug('retrieving url of last matching call');
 	return (this.lastCall(nameOrMatcher, options) || [])[0];
-};
+});
 
-FetchMock.lastOptions = function(nameOrMatcher, options) {
+FetchMock.lastOptions = formatDebug(function(nameOrMatcher, options) {
+	debug('retrieving options of last matching call');
 	return (this.lastCall(nameOrMatcher, options) || [])[1];
-};
+});
 
-FetchMock.called = function(nameOrMatcher, options) {
+FetchMock.called = formatDebug(function(nameOrMatcher, options) {
+	debug('checking if matching call was made');
 	return !!this.filterCalls(nameOrMatcher, options).length;
-};
+});
+
+FetchMock.flush = formatDebug(async function(waitForResponseMethods) {
+	setDebugNamespace('flush')
+	debug(`flushing all fetch calls. ${waitForResponseMethods ? '' : 'Not '}waiting for response bodies to complete download`);
 
-FetchMock.flush = function(waitForResponseMethods) {
 	const queuedPromises = this._holdingPromises;
 	this._holdingPromises = [];
-
-	return Promise.all(queuedPromises).then(() => {
-		if (waitForResponseMethods && this._holdingPromises.length) {
-			return this.flush(waitForResponseMethods);
+	debug(`${queuedPromises.length} fetch calls to be awaited`)
+
+	await Promise.all(queuedPromises)
+	debug(`All fetch calls have completed`)
+	if (waitForResponseMethods && this._holdingPromises.length) {
+		debug(`Awaiting all fetch bodies to download`)
+		await this.flush(waitForResponseMethods);
+		debug(`All fetch bodies have completed downloading`)
+	}
+	setDebugNamespace()
+});
+
+FetchMock.done = formatDebug(function(nameOrMatcher) {
+	setDebugPhase('inspect')
+	setDebugNamespace('done')
+	debug('Checking to see if expected calls have been made')
+	let routesToCheck;
+
+
+		if(nameOrMatcher && typeof nameOrMatcher !== 'boolean') {
+			debug('Checking to see if expected calls have been made for single route:', nameOrMatcher)
+			routesToCheck = [{ identifier: nameOrMatcher }]
+		} else {
+			debug('Checking to see if expected calls have been made for all routes')
+			routesToCheck = this.routes;
 		}
-	});
-};
 
-FetchMock.done = function(nameOrMatcher) {
-	const routesToCheck =
-		nameOrMatcher && typeof nameOrMatcher !== 'boolean'
-			? [{ identifier: nameOrMatcher }]
-			: this.routes;
 
 	// Can't use array.every because would exit after first failure, which would
 	// break the logging
-	return routesToCheck
+	const result = routesToCheck
 		.map(({ identifier }) => {
 			if (!this.called(identifier)) {
+				debug('No calls made for route:', identifier)
 				console.warn(`Warning: ${identifier} not called`); // eslint-disable-line
 				return false;
 			}
@@ -89,10 +132,14 @@ FetchMock.done = function(nameOrMatcher) {
 			).repeat;
 
 			if (!expectedTimes) {
+				debug('Route has been called at least once, and no expectation of more set:', identifier)
 				return true;
 			}
 			const actualTimes = this.filterCalls(identifier).length;
+
+			debug(`Route called ${actualTimes} times:`, identifier)
 			if (expectedTimes > actualTimes) {
+				debug(`Route called ${actualTimes} times, but expected ${expectedTimes}:`, identifier)
 				console.warn(
 					`Warning: ${identifier} only called ${actualTimes} times, but ${expectedTimes} expected`
 				); // eslint-disable-line
@@ -102,6 +149,10 @@ FetchMock.done = function(nameOrMatcher) {
 			}
 		})
 		.every(isDone => isDone);
-};
+
+		setDebugNamespace()
+		setDebugPhase()
+		return result
+});
 
 module.exports = FetchMock;
diff --git a/src/lib/request-utils.js b/src/lib/request-utils.js
index 319c00f2..9dd570fe 100644
--- a/src/lib/request-utils.js
+++ b/src/lib/request-utils.js
@@ -1,3 +1,4 @@
+const {debug} = require('./debug');
 let URL;
 // https://stackoverflow.com/a/19709846/308237
 const absoluteUrlRX = new RegExp('^(?:[a-z]+:)?//', 'i');
diff --git a/src/lib/response-builder.js b/src/lib/response-builder.js
index e9482b24..24f884b1 100644
--- a/src/lib/response-builder.js
+++ b/src/lib/response-builder.js
@@ -1,3 +1,4 @@
+const {debug} = require('./debug');
 const responseConfigProps = [
 	'body',
 	'headers',
diff --git a/src/lib/set-up-and-tear-down.js b/src/lib/set-up-and-tear-down.js
index 9c010d9c..ddfbc3ae 100644
--- a/src/lib/set-up-and-tear-down.js
+++ b/src/lib/set-up-and-tear-down.js
@@ -1,8 +1,9 @@
-const debug = require('debug')('fetch-mock');
+const {debug, setDebugPhase} = require('./debug');
 const { compileRoute } = require('./compile-route');
 const FetchMock = {};
 
 FetchMock.mock = function(...args) {
+	setDebugPhase('setup');
 	if (args.length) {
 		this.addRoute(args);
 	}
@@ -26,8 +27,6 @@ FetchMock.addRoute = function(uncompiledRoute) {
 
 	if (overwriteRoutes === false || !clashes.length) {
 		this._uncompiledRoutes.push(uncompiledRoute);
-		debug('Route added successfully')
-		debug('---------------')
 		return this.routes.push(route);
 	}
 
@@ -37,8 +36,6 @@ FetchMock.addRoute = function(uncompiledRoute) {
 			this._uncompiledRoutes.splice(index, 1, uncompiledRoute);
 			this.routes.splice(index, 1, route);
 		});
-		debug('Route added successfully')
-		debug('---------------')
 		return this.routes;
 	}
 
@@ -50,8 +47,6 @@ FetchMock.addRoute = function(uncompiledRoute) {
 
 	this._uncompiledRoutes.push(uncompiledRoute);
 	this.routes.push(route);
-	debug('Route added successfully')
-	debug('---------------')
 
 };
 
@@ -61,6 +56,7 @@ FetchMock._mock = function() {
 		this.realFetch = this.realFetch || this.global.fetch;
 		this.global.fetch = this.fetchHandler;
 	}
+	setDebugPhase();
 	return this;
 };
 

From 8c2f83379cd4e6b641712c06f01c950e68ee9260 Mon Sep 17 00:00:00 2001
From: Rhys Evans <rhys.evans@ft.com>
Date: Sat, 25 Jan 2020 21:16:44 +0000
Subject: [PATCH 09/12] most debug messages are done

---
 src/lib/compile-route.js | 10 +++++++---
 src/lib/debug.js         |  7 ++++---
 2 files changed, 11 insertions(+), 6 deletions(-)

diff --git a/src/lib/compile-route.js b/src/lib/compile-route.js
index 630deec2..8d543323 100644
--- a/src/lib/compile-route.js
+++ b/src/lib/compile-route.js
@@ -1,4 +1,4 @@
-const {debug, setDebugNamespace} = require('./debug');
+const {debug, getDebug, setDebugNamespace} = require('./debug');
 const generateMatcher = require('./generate-matcher');
 
 const matcherProperties = [
@@ -38,6 +38,7 @@ const argsToRoute = args => {
 };
 
 const sanitizeRoute = route => {
+	const debug = getDebug('sanitizeRoute()');
 	debug('Sanitizing route properties');
 	route = Object.assign({}, route);
 
@@ -74,7 +75,8 @@ const validateRoute = route => {
 	}
 };
 
-const limitMatcher = route => {
+const limit = route => {
+	const debug = getDebug('limit()');
 	debug('Limiting number of requests to handle by route');
 	if (!route.repeat) {
 		debug('  No `repeat` value set on route. Will match any number of requests');
@@ -95,6 +97,7 @@ const limitMatcher = route => {
 };
 
 const delayResponse = route => {
+	const debug = getDebug('delayResponse()');
 	debug(`Applying response delay settings`)
 	const { delay } = route;
 	if (delay) {
@@ -110,12 +113,13 @@ const delayResponse = route => {
 };
 
 const compileRoute = function(args) {
+	const debug = getDebug('compileRoute()');
 	setDebugNamespace('compile');
 	debug('Compiling route');
 	const route = sanitizeRoute(argsToRoute(args));
 	validateRoute(route);
 	route.matcher = generateMatcher(route);
-	limitMatcher(route);
+	limit(route);
 	delayResponse(route);
 	setDebugNamespace();
 	return route;
diff --git a/src/lib/debug.js b/src/lib/debug.js
index 4f4db385..4d5e5eab 100644
--- a/src/lib/debug.js
+++ b/src/lib/debug.js
@@ -3,8 +3,8 @@ const debug = require('debug');
 let debugFunc
 let phase = 'default';
 let namespace = '';
-const newDebug = () => {
-	debugFunc = namespace ? debug(`fetch-mock:${phase}:${namespace}`) : debug(`fetch-mock:${phase}`)
+const newDebug = (ns) => {
+	debugFunc = (ns || namespace) ? debug(`fetch-mock:${phase}:${namespace}`) : debug(`fetch-mock:${phase}`)
 }
 
 newDebug()
@@ -20,5 +20,6 @@ module.exports = {
 	setDebugPhase: str => {
 		phase = str || 'default';
 		newDebug();
-	}
+	},
+	getDebug = (namespace) => newDebug(namespace);
 }

From 671130b614da253f60c21640c2dc07884bd52411 Mon Sep 17 00:00:00 2001
From: Rhys Evans <rhys.evans@ft.com>
Date: Sat, 25 Jan 2020 21:31:39 +0000
Subject: [PATCH 10/12] finalised debug logs

---
 src/lib/compile-route.js    |  2 --
 src/lib/debug.js            |  8 +++++---
 src/lib/fetch-handler.js    |  6 +++++-
 src/lib/generate-matcher.js |  4 +++-
 src/lib/response-builder.js | 17 ++++++++++++++++-
 5 files changed, 29 insertions(+), 8 deletions(-)

diff --git a/src/lib/compile-route.js b/src/lib/compile-route.js
index 8d543323..0a13f8a7 100644
--- a/src/lib/compile-route.js
+++ b/src/lib/compile-route.js
@@ -114,14 +114,12 @@ const delayResponse = route => {
 
 const compileRoute = function(args) {
 	const debug = getDebug('compileRoute()');
-	setDebugNamespace('compile');
 	debug('Compiling route');
 	const route = sanitizeRoute(argsToRoute(args));
 	validateRoute(route);
 	route.matcher = generateMatcher(route);
 	limit(route);
 	delayResponse(route);
-	setDebugNamespace();
 	return route;
 };
 
diff --git a/src/lib/debug.js b/src/lib/debug.js
index 4d5e5eab..1ff215fd 100644
--- a/src/lib/debug.js
+++ b/src/lib/debug.js
@@ -3,10 +3,12 @@ const debug = require('debug');
 let debugFunc
 let phase = 'default';
 let namespace = '';
-const newDebug = (ns) => {
-	debugFunc = (ns || namespace) ? debug(`fetch-mock:${phase}:${namespace}`) : debug(`fetch-mock:${phase}`)
+const newDebug = () => {
+	debugFunc = namespace ? debug(`fetch-mock:${phase}:${namespace}`) : debug(`fetch-mock:${phase}`)
 }
 
+const newDebugSandbox = (ns) => debug(`fetch-mock:${phase}:${ns}`);
+
 newDebug()
 
 module.exports = {
@@ -21,5 +23,5 @@ module.exports = {
 		phase = str || 'default';
 		newDebug();
 	},
-	getDebug = (namespace) => newDebug(namespace);
+	getDebug: (namespace) => newDebugSandbox(namespace)
 }
diff --git a/src/lib/fetch-handler.js b/src/lib/fetch-handler.js
index f566e32d..ee00cd92 100755
--- a/src/lib/fetch-handler.js
+++ b/src/lib/fetch-handler.js
@@ -1,4 +1,4 @@
-const {debug, setDebugPhase} = require('./debug');
+const {debug, setDebugPhase, getDebug} = require('./debug');
 const responseBuilder = require('./response-builder');
 const requestUtils = require('./request-utils');
 const FetchMock = {};
@@ -24,6 +24,7 @@ const resolve = async (
 	options,
 	request
 ) => {
+	const debug = getDebug('resolve()');
 	debug('Recursively resolving function and promise responses');
 	// We want to allow things like
 	// - function returning a Promise for a response
@@ -62,6 +63,7 @@ const resolve = async (
 
 FetchMock.fetchHandler = function(url, options, request) {
 	setDebugPhase('handle');
+	const debug = getDebug('fetchHandler()');
 	debug('fetch called with:', url, options)
 	const normalizedRequest = requestUtils.normalizeRequest(
 		url,
@@ -119,6 +121,7 @@ FetchMock.fetchHandler = function(url, options, request) {
 FetchMock.fetchHandler.isMock = true;
 
 FetchMock.executeRouter = function(url, options, request) {
+	const debug = getDebug('executeRouter()');
 	debug(`Attempting to match request to a route`);
 	if (this.config.fallbackToNetwork === 'always') {
 		debug(
@@ -158,6 +161,7 @@ FetchMock.executeRouter = function(url, options, request) {
 };
 
 FetchMock.generateResponse = async function(route, url, options, request) {
+	const debug = getDebug('generateResponse()');
 	const response = await resolve(route, url, options, request);
 
 	// If the response says to throw an error, throw it
diff --git a/src/lib/generate-matcher.js b/src/lib/generate-matcher.js
index caef1d0a..3bf8588f 100644
--- a/src/lib/generate-matcher.js
+++ b/src/lib/generate-matcher.js
@@ -1,4 +1,4 @@
-const {debug} = require('./debug');
+const {debug, getDebug, setDebugNamespace} = require('./debug');
 const glob = require('glob-to-regexp');
 const pathToRegexp = require('path-to-regexp');
 const querystring = require('querystring');
@@ -203,6 +203,7 @@ const getUrlMatcher = route => {
 };
 
 module.exports = route => {
+	setDebugNamespace('generateMatcher()')
 	debug('Compiling matcher for route');
 	const matchers = [
 		route.query && getQueryStringMatcher(route),
@@ -215,6 +216,7 @@ module.exports = route => {
 	].filter(matcher => !!matcher);
 
 	debug('Compiled matcher for route');
+	setDebugNamespace()
 	return (url, options = {}, request) =>
 		matchers.every(matcher => matcher(url, options, request));
 };
diff --git a/src/lib/response-builder.js b/src/lib/response-builder.js
index 24f884b1..ddb38b84 100644
--- a/src/lib/response-builder.js
+++ b/src/lib/response-builder.js
@@ -1,4 +1,4 @@
-const {debug} = require('./debug');
+const {debug, getDebug} = require('./debug');
 const responseConfigProps = [
 	'body',
 	'headers',
@@ -9,10 +9,13 @@ const responseConfigProps = [
 
 class ResponseBuilder {
 	constructor(options) {
+		this.debug = getDebug('ResponseBuilder()');
+		this.debug('Response builder created with options', options)
 		Object.assign(this, options);
 	}
 
 	exec() {
+		this.debug('building response')
 		this.normalizeResponseConfig();
 		this.constructFetchOpts();
 		this.constructResponseBody();
@@ -40,12 +43,14 @@ class ResponseBuilder {
 	normalizeResponseConfig() {
 		// If the response config looks like a status, start to generate a simple response
 		if (typeof this.responseConfig === 'number') {
+			this.debug('building response using status', this.responseConfig)
 			this.responseConfig = {
 				status: this.responseConfig
 			};
 			// If the response config is not an object, or is an object that doesn't use
 			// any reserved properties, assume it is meant to be the body of the response
 		} else if (typeof this.responseConfig === 'string' || this.sendAsObject()) {
+			this.debug('building text response from', this.responseConfig)
 			this.responseConfig = {
 				body: this.responseConfig
 			};
@@ -54,6 +59,7 @@ class ResponseBuilder {
 
 	validateStatus(status) {
 		if (!status) {
+			this.debug('No status provided. Defaulting to 200')
 			return 200;
 		}
 
@@ -63,6 +69,7 @@ class ResponseBuilder {
 				status >= 200) ||
 			status < 600
 		) {
+			this.debug('Valid status provided', status)
 			return status;
 		}
 
@@ -97,6 +104,7 @@ e.g. {"body": {"status: "registered"}}`);
 			this.responseConfig.body != null && //eslint-disable-line
 			typeof this.body === 'object'
 		) {
+			this.debug('Stringifying JSON response body')
 			this.body = JSON.stringify(this.body);
 			if (!this.options.headers.has('Content-Type')) {
 				this.options.headers.set('Content-Type', 'application/json');
@@ -111,6 +119,7 @@ e.g. {"body": {"status: "registered"}}`);
 			typeof this.body === 'string' &&
 			!this.options.headers.has('Content-Length')
 		) {
+			this.debug('Setting content-length header:', this.body.length.toString())
 			this.options.headers.set('Content-Length', this.body.length.toString());
 		}
 	}
@@ -124,6 +133,7 @@ e.g. {"body": {"status: "registered"}}`);
 		// On the server we need to manually construct the readable stream for the
 		// Response object (on the client this done automatically)
 		if (this.Stream) {
+			this.debug('Creating response stream')
 			const stream = new this.Stream.Readable();
 			if (this.body != null) { //eslint-disable-line
 				stream.push(this.body, 'utf-8');
@@ -140,21 +150,26 @@ e.g. {"body": {"status: "registered"}}`);
 		// Using a proxy means we can set properties that may not be writable on
 		// the original Response. It also means we can track the resolution of
 		// promises returned by res.json(), res.text() etc
+		this.debug('Wrappipng Response in ES proxy for observability')
 		return new Proxy(response, {
 			get: (originalResponse, name) => {
 				if (this.responseConfig.redirectUrl) {
 					if (name === 'url') {
+						this.debug('Retrieving redirect url', this.responseConfig.redirectUrl)
 						return this.responseConfig.redirectUrl;
 					}
 
 					if (name === 'redirected') {
+						this.debug('Retrieving redirected status', true)
 						return true;
 					}
 				}
 
 				if (typeof originalResponse[name] === 'function') {
+					this.debug('Wrapping body promises in ES proxies for observability')
 					return new Proxy(originalResponse[name], {
 						apply: (func, thisArg, args) => {
+							this.debug(`Calling res.${name}`)
 							const result = func.apply(response, args);
 							if (result.then) {
 								fetchMock._holdingPromises.push(result.catch(() => null));

From a575bb84ef339d7e4befa4cbae14cdaaedaf450c Mon Sep 17 00:00:00 2001
From: Rhys Evans <rhys.evans@ft.com>
Date: Sat, 25 Jan 2020 21:35:09 +0000
Subject: [PATCH 11/12] docs

---
 docs/_troubleshooting/troubleshooting.md |  2 ++
 docs/_usage/_defaults.md                 | 16 ----------------
 docs/_usage/debug-mode.md                |  6 ++++++
 3 files changed, 8 insertions(+), 16 deletions(-)
 delete mode 100644 docs/_usage/_defaults.md
 create mode 100644 docs/_usage/debug-mode.md

diff --git a/docs/_troubleshooting/troubleshooting.md b/docs/_troubleshooting/troubleshooting.md
index 2342334f..7f59edff 100644
--- a/docs/_troubleshooting/troubleshooting.md
+++ b/docs/_troubleshooting/troubleshooting.md
@@ -2,6 +2,8 @@
 title: General
 position: 1
 content_markdown: |-
+  The first  step when debugging tests should be to run with the environment variable `DEBUG=fetch-mock*`. This will output additional logs for debugging purposes.
+
   ### `fetch` is assigned to a local variable, not a global
 
   First of all, consider whether you could just use `fetch` as a global. Here are 3 reasons why this is a good idea:
diff --git a/docs/_usage/_defaults.md b/docs/_usage/_defaults.md
deleted file mode 100644
index 4c3e1fc8..00000000
--- a/docs/_usage/_defaults.md
+++ /dev/null
@@ -1,16 +0,0 @@
----
-title:
-position:
-parameters:
-  - name:
-    content:
-content_markdown:
-left_code_blocks:
-  - code_block:
-    title:
-    language:
-right_code_blocks:
-  - code_block:
-    title:
-    language:
----
diff --git a/docs/_usage/debug-mode.md b/docs/_usage/debug-mode.md
new file mode 100644
index 00000000..683f971f
--- /dev/null
+++ b/docs/_usage/debug-mode.md
@@ -0,0 +1,6 @@
+---
+title: Debugging
+position: 8
+content_markdown: |-
+  The first  step when debugging tests should be to run with the environment variable `DEBUG=fetch-mock*`. This will output additional logs for debugging purposes.
+---

From e6dff3258290b250f31538c5c1e5e79ddb0f9d7e Mon Sep 17 00:00:00 2001
From: Rhys Evans <rhys.evans@ft.com>
Date: Sat, 25 Jan 2020 21:36:57 +0000
Subject: [PATCH 12/12] lint

---
 src/lib/compile-route.js        |  20 +++---
 src/lib/debug.js                |  20 +++---
 src/lib/fetch-handler.js        |  30 +++++----
 src/lib/generate-matcher.js     |   6 +-
 src/lib/index.js                |   6 +-
 src/lib/inspecting.js           | 106 +++++++++++++++++++-------------
 src/lib/request-utils.js        |   1 -
 src/lib/response-builder.js     |  33 +++++-----
 src/lib/set-up-and-tear-down.js |   5 +-
 9 files changed, 129 insertions(+), 98 deletions(-)

diff --git a/src/lib/compile-route.js b/src/lib/compile-route.js
index 0a13f8a7..8a87d7f0 100644
--- a/src/lib/compile-route.js
+++ b/src/lib/compile-route.js
@@ -1,4 +1,4 @@
-const {debug, getDebug, setDebugNamespace} = require('./debug');
+const { getDebug } = require('./debug');
 const generateMatcher = require('./generate-matcher');
 
 const matcherProperties = [
@@ -47,7 +47,7 @@ const sanitizeRoute = route => {
 		route.method = route.method.toLowerCase();
 	}
 	if (isUrlMatcher(route.matcher)) {
-		debug('Mock uses a url matcher', route.matcher)
+		debug('Mock uses a url matcher', route.matcher);
 		route.url = route.matcher;
 		delete route.matcher;
 	}
@@ -79,7 +79,9 @@ const limit = route => {
 	const debug = getDebug('limit()');
 	debug('Limiting number of requests to handle by route');
 	if (!route.repeat) {
-		debug('  No `repeat` value set on route. Will match any number of requests');
+		debug(
+			'  No `repeat` value set on route. Will match any number of requests'
+		);
 		return;
 	}
 
@@ -98,17 +100,19 @@ const limit = route => {
 
 const delayResponse = route => {
 	const debug = getDebug('delayResponse()');
-	debug(`Applying response delay settings`)
+	debug(`Applying response delay settings`);
 	const { delay } = route;
 	if (delay) {
-		debug(`  Wrapping response in delay of ${delay} miliseconds`)
+		debug(`  Wrapping response in delay of ${delay} miliseconds`);
 		const response = route.response;
 		route.response = () => {
-			debug(`Delaying response by ${delay} miliseconds`)
+			debug(`Delaying response by ${delay} miliseconds`);
 			return new Promise(res => setTimeout(() => res(response), delay));
-		}
+		};
 	} else {
-		debug(`  No delay set on route. Will respond 'immediately' (but asynchronously)`)
+		debug(
+			`  No delay set on route. Will respond 'immediately' (but asynchronously)`
+		);
 	}
 };
 
diff --git a/src/lib/debug.js b/src/lib/debug.js
index 1ff215fd..c6c06f7a 100644
--- a/src/lib/debug.js
+++ b/src/lib/debug.js
@@ -1,27 +1,29 @@
 const debug = require('debug');
 
-let debugFunc
+let debugFunc;
 let phase = 'default';
 let namespace = '';
 const newDebug = () => {
-	debugFunc = namespace ? debug(`fetch-mock:${phase}:${namespace}`) : debug(`fetch-mock:${phase}`)
-}
+	debugFunc = namespace
+		? debug(`fetch-mock:${phase}:${namespace}`)
+		: debug(`fetch-mock:${phase}`);
+};
 
-const newDebugSandbox = (ns) => debug(`fetch-mock:${phase}:${ns}`);
+const newDebugSandbox = ns => debug(`fetch-mock:${phase}:${ns}`);
 
-newDebug()
+newDebug();
 
 module.exports = {
 	debug: (...args) => {
-		debugFunc(...args)
+		debugFunc(...args);
 	},
 	setDebugNamespace: str => {
-		namespace = str
+		namespace = str;
 		newDebug();
 	},
 	setDebugPhase: str => {
 		phase = str || 'default';
 		newDebug();
 	},
-	getDebug: (namespace) => newDebugSandbox(namespace)
-}
+	getDebug: namespace => newDebugSandbox(namespace)
+};
diff --git a/src/lib/fetch-handler.js b/src/lib/fetch-handler.js
index ee00cd92..3e335ec1 100755
--- a/src/lib/fetch-handler.js
+++ b/src/lib/fetch-handler.js
@@ -1,4 +1,4 @@
-const {debug, setDebugPhase, getDebug} = require('./debug');
+const { debug, setDebugPhase, getDebug } = require('./debug');
 const responseBuilder = require('./response-builder');
 const requestUtils = require('./request-utils');
 const FetchMock = {};
@@ -64,7 +64,7 @@ const resolve = async (
 FetchMock.fetchHandler = function(url, options, request) {
 	setDebugPhase('handle');
 	const debug = getDebug('fetchHandler()');
-	debug('fetch called with:', url, options)
+	debug('fetch called with:', url, options);
 	const normalizedRequest = requestUtils.normalizeRequest(
 		url,
 		options,
@@ -75,11 +75,11 @@ FetchMock.fetchHandler = function(url, options, request) {
 
 	const { signal } = normalizedRequest;
 
-	debug('Request normalised')
-	debug('  url', url)
-	debug('  options', options)
-	debug('  request', request)
-	debug('  signal', signal)
+	debug('Request normalised');
+	debug('  url', url);
+	debug('  options', options);
+	debug('  request', request);
+	debug('  signal', signal);
 
 	const route = this.executeRouter(url, options, request);
 
@@ -114,7 +114,7 @@ FetchMock.fetchHandler = function(url, options, request) {
 			.then(done, done)
 			.then(() => {
 				setDebugPhase();
-			})
+			});
 	});
 };
 
@@ -188,9 +188,9 @@ FetchMock.generateResponse = async function(route, url, options, request) {
 
 FetchMock.router = function(url, options, request) {
 	const route = this.routes.find((route, i) => {
-		debug(`Trying to match route ${i}`)
-		return route.matcher(url, options, request)
-			});
+		debug(`Trying to match route ${i}`);
+		return route.matcher(url, options, request);
+	});
 
 	if (route) {
 		this.push({
@@ -214,7 +214,13 @@ FetchMock.getNativeFetch = function() {
 };
 
 FetchMock.push = function({ url, options, request, isUnmatched, identifier }) {
-	debug('Recording fetch call', { url, options, request, isUnmatched, identifier })
+	debug('Recording fetch call', {
+		url,
+		options,
+		request,
+		isUnmatched,
+		identifier
+	});
 	const args = [url, options];
 	args.request = request;
 	args.identifier = identifier;
diff --git a/src/lib/generate-matcher.js b/src/lib/generate-matcher.js
index 3bf8588f..36b259f0 100644
--- a/src/lib/generate-matcher.js
+++ b/src/lib/generate-matcher.js
@@ -1,4 +1,4 @@
-const {debug, getDebug, setDebugNamespace} = require('./debug');
+const { debug, setDebugNamespace } = require('./debug');
 const glob = require('glob-to-regexp');
 const pathToRegexp = require('path-to-regexp');
 const querystring = require('querystring');
@@ -203,7 +203,7 @@ const getUrlMatcher = route => {
 };
 
 module.exports = route => {
-	setDebugNamespace('generateMatcher()')
+	setDebugNamespace('generateMatcher()');
 	debug('Compiling matcher for route');
 	const matchers = [
 		route.query && getQueryStringMatcher(route),
@@ -216,7 +216,7 @@ module.exports = route => {
 	].filter(matcher => !!matcher);
 
 	debug('Compiled matcher for route');
-	setDebugNamespace()
+	setDebugNamespace();
 	return (url, options = {}, request) =>
 		matchers.every(matcher => matcher(url, options, request));
 };
diff --git a/src/lib/index.js b/src/lib/index.js
index 601e8c87..8e296769 100644
--- a/src/lib/index.js
+++ b/src/lib/index.js
@@ -1,4 +1,4 @@
-const {debug} = require('./debug');
+const { debug } = require('./debug');
 const setUpAndTearDown = require('./set-up-and-tear-down');
 const fetchHandler = require('./fetch-handler');
 const inspecting = require('./inspecting');
@@ -14,7 +14,7 @@ FetchMock.config = {
 };
 
 FetchMock.createInstance = function() {
-	debug('Creating fetch-mock instance')
+	debug('Creating fetch-mock instance');
 	const instance = Object.create(FetchMock);
 	instance._uncompiledRoutes = (this._uncompiledRoutes || []).slice();
 	instance.routes = instance._uncompiledRoutes.map(config =>
@@ -36,7 +36,7 @@ FetchMock.bindMethods = function() {
 };
 
 FetchMock.sandbox = function() {
-	debug('Creating sandboxed fetch-mock instance')
+	debug('Creating sandboxed fetch-mock instance');
 	// this construct allows us to create a fetch-mock instance which is also
 	// a callable function, while circumventing circularity when defining the
 	// object that this function should be bound to
diff --git a/src/lib/inspecting.js b/src/lib/inspecting.js
index 3ab95a2a..b2d87518 100644
--- a/src/lib/inspecting.js
+++ b/src/lib/inspecting.js
@@ -1,4 +1,4 @@
-const {setDebugPhase, setDebugNamespace, debug} = require('./debug');
+const { setDebugPhase, setDebugNamespace, debug } = require('./debug');
 const { normalizeUrl } = require('./request-utils');
 const FetchMock = {};
 const { sanitizeRoute } = require('./compile-route');
@@ -11,50 +11,57 @@ const filterCallsWithMatcher = (matcher, options = {}, calls) => {
 	return calls.filter(([url, options]) => matcher(normalizeUrl(url), options));
 };
 
-const formatDebug = (func) => {
-	return function (...args) {
-		setDebugPhase('inspect')
+const formatDebug = func => {
+	return function(...args) {
+		setDebugPhase('inspect');
 		const result = func.call(this, ...args);
-		setDebugPhase()
+		setDebugPhase();
 		return result;
-	}
-}
+	};
+};
 
 FetchMock.filterCalls = function(nameOrMatcher, options) {
-	debug('Filtering fetch calls')
+	debug('Filtering fetch calls');
 	let calls = this._calls;
 	let matcher = '*';
 
 	if ([true, 'matched'].includes(nameOrMatcher)) {
-		debug(`Filter provided is ${nameOrMatcher}. Returning matched calls only`)
+		debug(`Filter provided is ${nameOrMatcher}. Returning matched calls only`);
 		calls = calls.filter(({ isUnmatched }) => !isUnmatched);
-
 	} else if ([false, 'unmatched'].includes(nameOrMatcher)) {
-		debug(`Filter provided is ${nameOrMatcher}. Returning unmatched calls only`)
+		debug(
+			`Filter provided is ${nameOrMatcher}. Returning unmatched calls only`
+		);
 		calls = calls.filter(({ isUnmatched }) => isUnmatched);
 	} else if (typeof nameOrMatcher === 'undefined') {
-		debug(`Filter provided is undefined. Returning all calls`)
+		debug(`Filter provided is undefined. Returning all calls`);
 		calls = calls;
 	} else if (isName(nameOrMatcher)) {
-		debug(`Filter provided, looks like the name of a named route. Returning only calls handled by that route`)
+		debug(
+			`Filter provided, looks like the name of a named route. Returning only calls handled by that route`
+		);
 		calls = calls.filter(({ identifier }) => identifier === nameOrMatcher);
 	} else {
 		matcher = normalizeUrl(nameOrMatcher);
 		if (this.routes.some(({ identifier }) => identifier === matcher)) {
-			debug(`Filter provided, ${nameOrMatcher}, identifies a route. Returning only calls handled by that route`)
+			debug(
+				`Filter provided, ${nameOrMatcher}, identifies a route. Returning only calls handled by that route`
+			);
 			calls = calls.filter(call => call.identifier === matcher);
 		}
 	}
 
-
 	if ((options || matcher !== '*') && calls.length) {
 		if (typeof options === 'string') {
 			options = { method: options };
 		}
-		debug('Compiling filter and options to route in order to filter all calls', nameOrMatcher)
+		debug(
+			'Compiling filter and options to route in order to filter all calls',
+			nameOrMatcher
+		);
 		calls = filterCallsWithMatcher(matcher, options, calls);
 	}
-	debug(`Retrieved ${calls.length} calls`)
+	debug(`Retrieved ${calls.length} calls`);
 	return calls;
 };
 
@@ -84,45 +91,50 @@ FetchMock.called = formatDebug(function(nameOrMatcher, options) {
 });
 
 FetchMock.flush = formatDebug(async function(waitForResponseMethods) {
-	setDebugNamespace('flush')
-	debug(`flushing all fetch calls. ${waitForResponseMethods ? '' : 'Not '}waiting for response bodies to complete download`);
+	setDebugNamespace('flush');
+	debug(
+		`flushing all fetch calls. ${
+			waitForResponseMethods ? '' : 'Not '
+		}waiting for response bodies to complete download`
+	);
 
 	const queuedPromises = this._holdingPromises;
 	this._holdingPromises = [];
-	debug(`${queuedPromises.length} fetch calls to be awaited`)
+	debug(`${queuedPromises.length} fetch calls to be awaited`);
 
-	await Promise.all(queuedPromises)
-	debug(`All fetch calls have completed`)
+	await Promise.all(queuedPromises);
+	debug(`All fetch calls have completed`);
 	if (waitForResponseMethods && this._holdingPromises.length) {
-		debug(`Awaiting all fetch bodies to download`)
+		debug(`Awaiting all fetch bodies to download`);
 		await this.flush(waitForResponseMethods);
-		debug(`All fetch bodies have completed downloading`)
+		debug(`All fetch bodies have completed downloading`);
 	}
-	setDebugNamespace()
+	setDebugNamespace();
 });
 
 FetchMock.done = formatDebug(function(nameOrMatcher) {
-	setDebugPhase('inspect')
-	setDebugNamespace('done')
-	debug('Checking to see if expected calls have been made')
+	setDebugPhase('inspect');
+	setDebugNamespace('done');
+	debug('Checking to see if expected calls have been made');
 	let routesToCheck;
 
-
-		if(nameOrMatcher && typeof nameOrMatcher !== 'boolean') {
-			debug('Checking to see if expected calls have been made for single route:', nameOrMatcher)
-			routesToCheck = [{ identifier: nameOrMatcher }]
-		} else {
-			debug('Checking to see if expected calls have been made for all routes')
-			routesToCheck = this.routes;
-		}
-
+	if (nameOrMatcher && typeof nameOrMatcher !== 'boolean') {
+		debug(
+			'Checking to see if expected calls have been made for single route:',
+			nameOrMatcher
+		);
+		routesToCheck = [{ identifier: nameOrMatcher }];
+	} else {
+		debug('Checking to see if expected calls have been made for all routes');
+		routesToCheck = this.routes;
+	}
 
 	// Can't use array.every because would exit after first failure, which would
 	// break the logging
 	const result = routesToCheck
 		.map(({ identifier }) => {
 			if (!this.called(identifier)) {
-				debug('No calls made for route:', identifier)
+				debug('No calls made for route:', identifier);
 				console.warn(`Warning: ${identifier} not called`); // eslint-disable-line
 				return false;
 			}
@@ -132,14 +144,20 @@ FetchMock.done = formatDebug(function(nameOrMatcher) {
 			).repeat;
 
 			if (!expectedTimes) {
-				debug('Route has been called at least once, and no expectation of more set:', identifier)
+				debug(
+					'Route has been called at least once, and no expectation of more set:',
+					identifier
+				);
 				return true;
 			}
 			const actualTimes = this.filterCalls(identifier).length;
 
-			debug(`Route called ${actualTimes} times:`, identifier)
+			debug(`Route called ${actualTimes} times:`, identifier);
 			if (expectedTimes > actualTimes) {
-				debug(`Route called ${actualTimes} times, but expected ${expectedTimes}:`, identifier)
+				debug(
+					`Route called ${actualTimes} times, but expected ${expectedTimes}:`,
+					identifier
+				);
 				console.warn(
 					`Warning: ${identifier} only called ${actualTimes} times, but ${expectedTimes} expected`
 				); // eslint-disable-line
@@ -150,9 +168,9 @@ FetchMock.done = formatDebug(function(nameOrMatcher) {
 		})
 		.every(isDone => isDone);
 
-		setDebugNamespace()
-		setDebugPhase()
-		return result
+	setDebugNamespace();
+	setDebugPhase();
+	return result;
 });
 
 module.exports = FetchMock;
diff --git a/src/lib/request-utils.js b/src/lib/request-utils.js
index 9dd570fe..319c00f2 100644
--- a/src/lib/request-utils.js
+++ b/src/lib/request-utils.js
@@ -1,4 +1,3 @@
-const {debug} = require('./debug');
 let URL;
 // https://stackoverflow.com/a/19709846/308237
 const absoluteUrlRX = new RegExp('^(?:[a-z]+:)?//', 'i');
diff --git a/src/lib/response-builder.js b/src/lib/response-builder.js
index ddb38b84..cdacf2dc 100644
--- a/src/lib/response-builder.js
+++ b/src/lib/response-builder.js
@@ -1,4 +1,4 @@
-const {debug, getDebug} = require('./debug');
+const { getDebug } = require('./debug');
 const responseConfigProps = [
 	'body',
 	'headers',
@@ -10,12 +10,12 @@ const responseConfigProps = [
 class ResponseBuilder {
 	constructor(options) {
 		this.debug = getDebug('ResponseBuilder()');
-		this.debug('Response builder created with options', options)
+		this.debug('Response builder created with options', options);
 		Object.assign(this, options);
 	}
 
 	exec() {
-		this.debug('building response')
+		this.debug('building response');
 		this.normalizeResponseConfig();
 		this.constructFetchOpts();
 		this.constructResponseBody();
@@ -43,14 +43,14 @@ class ResponseBuilder {
 	normalizeResponseConfig() {
 		// If the response config looks like a status, start to generate a simple response
 		if (typeof this.responseConfig === 'number') {
-			this.debug('building response using status', this.responseConfig)
+			this.debug('building response using status', this.responseConfig);
 			this.responseConfig = {
 				status: this.responseConfig
 			};
 			// If the response config is not an object, or is an object that doesn't use
 			// any reserved properties, assume it is meant to be the body of the response
 		} else if (typeof this.responseConfig === 'string' || this.sendAsObject()) {
-			this.debug('building text response from', this.responseConfig)
+			this.debug('building text response from', this.responseConfig);
 			this.responseConfig = {
 				body: this.responseConfig
 			};
@@ -59,7 +59,7 @@ class ResponseBuilder {
 
 	validateStatus(status) {
 		if (!status) {
-			this.debug('No status provided. Defaulting to 200')
+			this.debug('No status provided. Defaulting to 200');
 			return 200;
 		}
 
@@ -69,7 +69,7 @@ class ResponseBuilder {
 				status >= 200) ||
 			status < 600
 		) {
-			this.debug('Valid status provided', status)
+			this.debug('Valid status provided', status);
 			return status;
 		}
 
@@ -104,7 +104,7 @@ e.g. {"body": {"status: "registered"}}`);
 			this.responseConfig.body != null && //eslint-disable-line
 			typeof this.body === 'object'
 		) {
-			this.debug('Stringifying JSON response body')
+			this.debug('Stringifying JSON response body');
 			this.body = JSON.stringify(this.body);
 			if (!this.options.headers.has('Content-Type')) {
 				this.options.headers.set('Content-Type', 'application/json');
@@ -119,7 +119,7 @@ e.g. {"body": {"status: "registered"}}`);
 			typeof this.body === 'string' &&
 			!this.options.headers.has('Content-Length')
 		) {
-			this.debug('Setting content-length header:', this.body.length.toString())
+			this.debug('Setting content-length header:', this.body.length.toString());
 			this.options.headers.set('Content-Length', this.body.length.toString());
 		}
 	}
@@ -133,7 +133,7 @@ e.g. {"body": {"status: "registered"}}`);
 		// On the server we need to manually construct the readable stream for the
 		// Response object (on the client this done automatically)
 		if (this.Stream) {
-			this.debug('Creating response stream')
+			this.debug('Creating response stream');
 			const stream = new this.Stream.Readable();
 			if (this.body != null) { //eslint-disable-line
 				stream.push(this.body, 'utf-8');
@@ -150,26 +150,29 @@ e.g. {"body": {"status: "registered"}}`);
 		// Using a proxy means we can set properties that may not be writable on
 		// the original Response. It also means we can track the resolution of
 		// promises returned by res.json(), res.text() etc
-		this.debug('Wrappipng Response in ES proxy for observability')
+		this.debug('Wrappipng Response in ES proxy for observability');
 		return new Proxy(response, {
 			get: (originalResponse, name) => {
 				if (this.responseConfig.redirectUrl) {
 					if (name === 'url') {
-						this.debug('Retrieving redirect url', this.responseConfig.redirectUrl)
+						this.debug(
+							'Retrieving redirect url',
+							this.responseConfig.redirectUrl
+						);
 						return this.responseConfig.redirectUrl;
 					}
 
 					if (name === 'redirected') {
-						this.debug('Retrieving redirected status', true)
+						this.debug('Retrieving redirected status', true);
 						return true;
 					}
 				}
 
 				if (typeof originalResponse[name] === 'function') {
-					this.debug('Wrapping body promises in ES proxies for observability')
+					this.debug('Wrapping body promises in ES proxies for observability');
 					return new Proxy(originalResponse[name], {
 						apply: (func, thisArg, args) => {
-							this.debug(`Calling res.${name}`)
+							this.debug(`Calling res.${name}`);
 							const result = func.apply(response, args);
 							if (result.then) {
 								fetchMock._holdingPromises.push(result.catch(() => null));
diff --git a/src/lib/set-up-and-tear-down.js b/src/lib/set-up-and-tear-down.js
index ddfbc3ae..39e2d3ba 100644
--- a/src/lib/set-up-and-tear-down.js
+++ b/src/lib/set-up-and-tear-down.js
@@ -1,4 +1,4 @@
-const {debug, setDebugPhase} = require('./debug');
+const { debug, setDebugPhase } = require('./debug');
 const { compileRoute } = require('./compile-route');
 const FetchMock = {};
 
@@ -12,7 +12,7 @@ FetchMock.mock = function(...args) {
 };
 
 FetchMock.addRoute = function(uncompiledRoute) {
-	debug('Adding route', uncompiledRoute)
+	debug('Adding route', uncompiledRoute);
 	const route = this.compileRoute(uncompiledRoute);
 	const clashes = this.routes.filter(
 		({ identifier, method }) =>
@@ -47,7 +47,6 @@ FetchMock.addRoute = function(uncompiledRoute) {
 
 	this._uncompiledRoutes.push(uncompiledRoute);
 	this.routes.push(route);
-
 };
 
 FetchMock._mock = function() {