From 4138b80c5eb571e9b080868e7c9d8f7f49d11ec5 Mon Sep 17 00:00:00 2001
From: Matt Lewis <matthew.lewis@socialsignin.co.uk>
Date: Sat, 23 Dec 2017 18:13:10 +0000
Subject: [PATCH] fix: prepend the webpack context to the source root if not
 set Closes #32

---
 src/reporter.js   |  2 +-
 src/util.js       | 10 +++++++++-
 test/util.spec.js | 34 ++++++++++++++++++++++++++++++++++
 3 files changed, 44 insertions(+), 2 deletions(-)

diff --git a/src/reporter.js b/src/reporter.js
index e817567..6103399 100644
--- a/src/reporter.js
+++ b/src/reporter.js
@@ -61,7 +61,7 @@ function CoverageIstanbulReporter(baseReporterDecorator, logger, config) {
       Object.keys(coverage).forEach(filename => {
         const fileCoverage = coverage[filename];
         if (fileCoverage.inputSourceMap && coverageIstanbulReporter.fixWebpackSourcePaths) {
-          fileCoverage.inputSourceMap = util.fixWebpackSourcePaths(fileCoverage.inputSourceMap);
+          fileCoverage.inputSourceMap = util.fixWebpackSourcePaths(fileCoverage.inputSourceMap, config.webpack);
         }
         if (
           coverageIstanbulReporter.skipFilesWithNoCoverage &&
diff --git a/src/util.js b/src/util.js
index 2198094..ef5761e 100644
--- a/src/util.js
+++ b/src/util.js
@@ -22,8 +22,16 @@ function fixWebpackFilePath(filePath) {
   return filePath;
 }
 
-function fixWebpackSourcePaths(sourceMap) {
+function fixWebpackSourcePaths(sourceMap, webpackConfig) {
+  let sourceRoot = sourceMap.sourceRoot;
+  // Fix for https://github.com/mattlewis92/karma-coverage-istanbul-reporter/issues/32
+  // The sourceRoot is relative to the project directory and not an absolute path, so add the webpack context to it if set
+  if (webpackConfig && webpackConfig.context && sourceMap.sourceRoot && !sourceMap.sourceRoot.startsWith(webpackConfig.context)) {
+    sourceRoot = path.join(webpackConfig.context, sourceRoot);
+  }
+
   return Object.assign({}, sourceMap, {
+    sourceRoot: sourceRoot, // eslint-disable-line object-shorthand
     sources: (sourceMap.sources || []).map(source => {
       source = fixWebpackFilePath(source);
       if (sourceMap.sourceRoot && source.startsWith(sourceMap.sourceRoot)) {
diff --git a/test/util.spec.js b/test/util.spec.js
index b109b7d..336b312 100644
--- a/test/util.spec.js
+++ b/test/util.spec.js
@@ -108,5 +108,39 @@ describe('util', () => {
 
       expect(fixWebpackSourcePaths(input)).to.deep.equal(output);
     });
+
+    it('should add the webpack context to the source root if not set', () => {
+      const input = {
+        file: 'example.ts',
+        sourceRoot: 'src',
+        sources: ['example.ts']
+      };
+
+      const output = {
+        file: 'example.ts',
+        sourceRoot: '/Users/mattlewis/Code/open-source/karma-coverage-istanbul-reporter/test/fixtures/typescript/src',
+        sources: ['example.ts']
+      };
+      expect(fixWebpackSourcePaths(input, {
+        context: '/Users/mattlewis/Code/open-source/karma-coverage-istanbul-reporter/test/fixtures/typescript'
+      })).to.deep.equal(output);
+    });
+
+    it('should only add the webpack context to the source root if not already set', () => {
+      const input = {
+        file: 'example.ts',
+        sourceRoot: '/Users/mattlewis/Code/open-source/karma-coverage-istanbul-reporter/test/fixtures/typescript/src',
+        sources: ['example.ts']
+      };
+
+      const output = {
+        file: 'example.ts',
+        sourceRoot: '/Users/mattlewis/Code/open-source/karma-coverage-istanbul-reporter/test/fixtures/typescript/src',
+        sources: ['example.ts']
+      };
+      expect(fixWebpackSourcePaths(input, {
+        context: '/Users/mattlewis/Code/open-source/karma-coverage-istanbul-reporter/test/fixtures/typescript'
+      })).to.deep.equal(output);
+    });
   });
 });