From fc7b27ea781b0f5a04391a011d486769f248349e Mon Sep 17 00:00:00 2001
From: Ruben Bridgewater <ruben@bridgewater.de>
Date: Thu, 12 Dec 2019 22:51:43 +0100
Subject: [PATCH] assert: implement `assert.match()` and
 `assert.doesNotMatch()`
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This adds a new functionality to the assertion module: a dedicated
check for regular expressions. So far it's possible to use
`assert.ok(regexp.test(string))`. This is not ideal though when it
comes to the error message, since it's not possible to know how
either of the input values look like. It's just known that the
assertion failed.
This allows to pass through the regular expression and the input
string. The string is then matched against the regular expression
and reports a expressive error message in case of a failure.

Backport-PR-URL: https://github.com/nodejs/node/pull/31431
PR-URL: https://github.com/nodejs/node/pull/30929
Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Stephen Belanger <admin@stephenbelanger.com>
---
 doc/api/assert.md            |  72 +++++++++++++++++++++++++
 lib/assert.js                |  52 ++++++++++++++++--
 test/parallel/test-assert.js | 100 +++++++++++++++++++++++++++++++++++
 3 files changed, 220 insertions(+), 4 deletions(-)

diff --git a/doc/api/assert.md b/doc/api/assert.md
index 585a9dff4b3e48..277f29880d5b24 100644
--- a/doc/api/assert.md
+++ b/doc/api/assert.md
@@ -425,6 +425,42 @@ parameter is undefined, a default error message is assigned. If the `message`
 parameter is an instance of an [`Error`][] then it will be thrown instead of the
 `AssertionError`.
 
+## `assert.doesNotMatch(string, regexp[, message])`
+<!-- YAML
+added: REPLACEME
+-->
+
+* `string` {string}
+* `regexp` {RegExp}
+* `message` {string|Error}
+
+> Stability: 1 - Experimental
+
+Expects the `string` input not to match the regular expression.
+
+This feature is currently experimental and the name might change or it might be
+completely removed again.
+
+```js
+const assert = require('assert').strict;
+
+assert.doesNotMatch('I will fail', /fail/);
+// AssertionError [ERR_ASSERTION]: The input was expected to not match the ...
+
+assert.doesNotMatch(123, /pass/);
+// AssertionError [ERR_ASSERTION]: The "string" argument must be of type string.
+
+assert.doesNotMatch('I will pass', /different/);
+// OK
+```
+
+If the values do match, or if the `string` argument is of another type than
+`string`, an [`AssertionError`][] is thrown with a `message` property set equal
+to the value of the `message` parameter. If the `message` parameter is
+undefined, a default error message is assigned. If the `message` parameter is an
+instance of an [`Error`][] then it will be thrown instead of the
+[`AssertionError`][].
+
 ## `assert.doesNotReject(asyncFn[, error][, message])`
 <!-- YAML
 added: v10.0.0
@@ -728,6 +764,42 @@ let err;
 //     at errorFrame
 ```
 
+## `assert.match(string, regexp[, message])`
+<!-- YAML
+added: REPLACEME
+-->
+
+* `string` {string}
+* `regexp` {RegExp}
+* `message` {string|Error}
+
+> Stability: 1 - Experimental
+
+Expects the `string` input to match the regular expression.
+
+This feature is currently experimental and the name might change or it might be
+completely removed again.
+
+```js
+const assert = require('assert').strict;
+
+assert.match('I will fail', /pass/);
+// AssertionError [ERR_ASSERTION]: The input did not match the regular ...
+
+assert.match(123, /pass/);
+// AssertionError [ERR_ASSERTION]: The "string" argument must be of type string.
+
+assert.match('I will pass', /pass/);
+// OK
+```
+
+If the values do not match, or if the `string` argument is of another type than
+`string`, an [`AssertionError`][] is thrown with a `message` property set equal
+to the value of the `message` parameter. If the `message` parameter is
+undefined, a default error message is assigned. If the `message` parameter is an
+instance of an [`Error`][] then it will be thrown instead of the
+[`AssertionError`][].
+
 ## `assert.notDeepEqual(actual, expected[, message])`
 <!-- YAML
 added: v0.1.21
diff --git a/lib/assert.js b/lib/assert.js
index 52523db3948ca7..f37166be9c6798 100644
--- a/lib/assert.js
+++ b/lib/assert.js
@@ -27,6 +27,7 @@ const {
   ObjectKeys,
   ObjectPrototypeIsPrototypeOf,
   Map,
+  RegExpPrototypeTest,
 } = primordials;
 
 const { Buffer } = require('buffer');
@@ -533,7 +534,7 @@ class Comparison {
         if (actual !== undefined &&
             typeof actual[key] === 'string' &&
             isRegExp(obj[key]) &&
-            obj[key].test(actual[key])) {
+            RegExpPrototypeTest(obj[key], actual[key])) {
           this[key] = actual[key];
         } else {
           this[key] = obj[key];
@@ -579,7 +580,7 @@ function expectedException(actual, expected, message, fn) {
     // Handle regular expressions.
     if (isRegExp(expected)) {
       const str = String(actual);
-      if (expected.test(str))
+      if (RegExpPrototypeTest(expected, str))
         return;
 
       if (!message) {
@@ -614,7 +615,7 @@ function expectedException(actual, expected, message, fn) {
       for (const key of keys) {
         if (typeof actual[key] === 'string' &&
             isRegExp(expected[key]) &&
-            expected[key].test(actual[key])) {
+            RegExpPrototypeTest(expected[key], actual[key])) {
           continue;
         }
         compareExceptionKey(actual, expected, key, message, keys, fn);
@@ -751,7 +752,7 @@ function hasMatchingError(actual, expected) {
   if (typeof expected !== 'function') {
     if (isRegExp(expected)) {
       const str = String(actual);
-      return expected.test(str);
+      return RegExpPrototypeTest(expected, str);
     }
     throw new ERR_INVALID_ARG_TYPE(
       'expected', ['Function', 'RegExp'], expected
@@ -856,6 +857,49 @@ assert.ifError = function ifError(err) {
   }
 };
 
+function internalMatch(string, regexp, message, fn) {
+  if (!isRegExp(regexp)) {
+    throw new ERR_INVALID_ARG_TYPE(
+      'regexp', 'RegExp', regexp
+    );
+  }
+  const match = fn.name === 'match';
+  if (typeof string !== 'string' ||
+      RegExpPrototypeTest(regexp, string) !== match) {
+    if (message instanceof Error) {
+      throw message;
+    }
+
+    const generatedMessage = !message;
+
+    // 'The input was expected to not match the regular expression ' +
+    message = message || (typeof string !== 'string' ?
+      'The "string" argument must be of type string. Received type ' +
+        `${typeof string} (${inspect(string)})` :
+      (match ?
+        'The input did not match the regular expression ' :
+        'The input was expected to not match the regular expression ') +
+          `${inspect(regexp)}. Input:\n\n${inspect(string)}\n`);
+    const err = new AssertionError({
+      actual: string,
+      expected: regexp,
+      message,
+      operator: fn.name,
+      stackStartFn: fn
+    });
+    err.generatedMessage = generatedMessage;
+    throw err;
+  }
+}
+
+assert.match = function match(string, regexp, message) {
+  internalMatch(string, regexp, message, match);
+};
+
+assert.doesNotMatch = function doesNotMatch(string, regexp, message) {
+  internalMatch(string, regexp, message, doesNotMatch);
+};
+
 // Expose a strict only variant of assert
 function strict(...args) {
   innerOk(strict, args.length, ...args);
diff --git a/test/parallel/test-assert.js b/test/parallel/test-assert.js
index f0204d52f51b5b..27421d2373eab1 100644
--- a/test/parallel/test-assert.js
+++ b/test/parallel/test-assert.js
@@ -1301,3 +1301,103 @@ assert.throws(
     assert(!err2.stack.includes('hidden'));
   })();
 }
+
+// Multiple assert.match() tests.
+{
+  assert.throws(
+    () => assert.match(/abc/, 'string'),
+    {
+      code: 'ERR_INVALID_ARG_TYPE',
+      message: 'The "regexp" argument must be an instance of RegExp. ' +
+               "Received type string ('string')"
+    }
+  );
+  assert.throws(
+    () => assert.match('string', /abc/),
+    {
+      actual: 'string',
+      expected: /abc/,
+      operator: 'match',
+      message: 'The input did not match the regular expression /abc/. ' +
+               "Input:\n\n'string'\n",
+      generatedMessage: true
+    }
+  );
+  assert.throws(
+    () => assert.match('string', /abc/, 'foobar'),
+    {
+      actual: 'string',
+      expected: /abc/,
+      operator: 'match',
+      message: 'foobar',
+      generatedMessage: false
+    }
+  );
+  const errorMessage = new RangeError('foobar');
+  assert.throws(
+    () => assert.match('string', /abc/, errorMessage),
+    errorMessage
+  );
+  assert.throws(
+    () => assert.match({ abc: 123 }, /abc/),
+    {
+      actual: { abc: 123 },
+      expected: /abc/,
+      operator: 'match',
+      message: 'The "string" argument must be of type string. ' +
+               'Received type object ({ abc: 123 })',
+      generatedMessage: true
+    }
+  );
+  assert.match('I will pass', /pass$/);
+}
+
+// Multiple assert.doesNotMatch() tests.
+{
+  assert.throws(
+    () => assert.doesNotMatch(/abc/, 'string'),
+    {
+      code: 'ERR_INVALID_ARG_TYPE',
+      message: 'The "regexp" argument must be an instance of RegExp. ' +
+               "Received type string ('string')"
+    }
+  );
+  assert.throws(
+    () => assert.doesNotMatch('string', /string/),
+    {
+      actual: 'string',
+      expected: /string/,
+      operator: 'doesNotMatch',
+      message: 'The input was expected to not match the regular expression ' +
+               "/string/. Input:\n\n'string'\n",
+      generatedMessage: true
+    }
+  );
+  assert.throws(
+    () => assert.doesNotMatch('string', /string/, 'foobar'),
+    {
+      actual: 'string',
+      expected: /string/,
+      operator: 'doesNotMatch',
+      message: 'foobar',
+      generatedMessage: false
+    }
+  );
+  const errorMessage = new RangeError('foobar');
+  assert.throws(
+    () => assert.doesNotMatch('string', /string/, errorMessage),
+    errorMessage
+  );
+  assert.throws(
+    () => assert.doesNotMatch({ abc: 123 }, /abc/),
+    {
+      actual: { abc: 123 },
+      expected: /abc/,
+      operator: 'doesNotMatch',
+      message: 'The "string" argument must be of type string. ' +
+               'Received type object ({ abc: 123 })',
+      generatedMessage: true
+    }
+  );
+  assert.doesNotMatch('I will pass', /different$/);
+}