From 3d9eaa4263e3db341092986e76fc5b972f7d87e8 Mon Sep 17 00:00:00 2001
From: Corey Farrell <git@cfware.com>
Date: Wed, 24 Apr 2019 14:12:31 -0400
Subject: [PATCH] fix: Purge source-map cache before reporting if cache is
 disabled. (#1080)

---
 bin/nyc.js          |  1 +
 index.js            |  6 ++++++
 lib/source-maps.js  |  8 ++++++--
 test/source-maps.js | 20 --------------------
 4 files changed, 13 insertions(+), 22 deletions(-)
 delete mode 100644 test/source-maps.js

diff --git a/bin/nyc.js b/bin/nyc.js
index 7c188e40a..97ef50b67 100755
--- a/bin/nyc.js
+++ b/bin/nyc.js
@@ -67,6 +67,7 @@ if ([
 
     nyc.writeProcessIndex()
 
+    nyc.maybePurgeSourceMapCache()
     if (argv.checkCoverage) {
       nyc.checkCoverage({
         lines: argv.lines,
diff --git a/index.js b/index.js
index 8c9d8e9a8..acf66ff19 100755
--- a/index.js
+++ b/index.js
@@ -236,6 +236,12 @@ class NYC {
     return this._transform(code, filename)
   }
 
+  maybePurgeSourceMapCache () {
+    if (!this.cache) {
+      this.sourceMaps.purgeCache()
+    }
+  }
+
   _transformFactory (cacheDir) {
     const instrumenter = this.instrumenter()
     let instrumented
diff --git a/lib/source-maps.js b/lib/source-maps.js
index c4840fc01..b36285d75 100644
--- a/lib/source-maps.js
+++ b/lib/source-maps.js
@@ -4,12 +4,16 @@ const libSourceMaps = require('istanbul-lib-source-maps')
 const fs = require('fs')
 const path = require('path')
 
-const sourceMapCache = libSourceMaps.createSourceMapStore()
 function SourceMaps (opts) {
   this.cache = opts.cache
   this.cacheDirectory = opts.cacheDirectory
   this.loadedMaps = {}
-  this._sourceMapCache = sourceMapCache
+  this._sourceMapCache = libSourceMaps.createSourceMapStore()
+}
+
+SourceMaps.prototype.purgeCache = function () {
+  this._sourceMapCache = libSourceMaps.createSourceMapStore()
+  this.loadedMaps = {}
 }
 
 SourceMaps.prototype.extractAndRegister = function (code, filename, hash) {
diff --git a/test/source-maps.js b/test/source-maps.js
deleted file mode 100644
index c95334832..000000000
--- a/test/source-maps.js
+++ /dev/null
@@ -1,20 +0,0 @@
-/* global describe, it */
-
-require('chai').should()
-require('tap').mochaGlobals()
-
-const { readFileSync } = require('fs')
-const SourceMaps = require('../self-coverage/lib/source-maps')
-
-describe('source-maps', function () {
-  it('caches source maps globally', function () {
-    const sm = new SourceMaps({})
-    // load a source map into cache.
-    const sourceFile = require.resolve('./fixtures/source-maps/instrumented/s1.min.js')
-    sm.extractAndRegister(readFileSync(sourceFile, 'utf8'), sourceFile, 'abc123')
-    // create a new SourceMaps instance.
-    const sm2 = new SourceMaps({})
-    // the two instances of SourceMaps should share a cache.
-    sm._sourceMapCache.should.deep.equal(sm2._sourceMapCache)
-  })
-})