Fix.

node_modules/istanbul-lib-source-maps/lib/source-store.js

@@ -0,0 +1,80 @@
+/*
+ Copyright 2015, Yahoo Inc.
+ Copyrights licensed under the New BSD License. See the accompanying LICENSE file for terms.
+ */
+'use strict';
+
+const fs = require('fs');
+const os = require('os');
+const path = require('path');
+const mkdirp = require('make-dir');
+const rimraf = require('rimraf');
+
+/* This exists for compatibility only to avoid changing the
+ * prototype chain. */
+class SourceStore {}
+
+class MemoryStore extends SourceStore {
+    constructor() {
+        super();
+
+        this.data = {};
+    }
+
+    registerSource(filePath, sourceText) {
+        this.data[filePath] = sourceText;
+    }
+
+    getSource(filePath) {
+        return this.data[filePath] || null;
+    }
+
+    dispose() {}
+}
+
+class FileStore extends SourceStore {
+    constructor(opts = {}) {
+        super();
+
+        const tmpDir = opts.tmpdir || os.tmpdir();
+        this.counter = 0;
+        this.mappings = [];
+        this.basePath = path.resolve(tmpDir, '.istanbul', 'cache_');
+        mkdirp.sync(path.dirname(this.basePath));
+    }
+
+    registerSource(filePath, sourceText) {
+        if (this.mappings[filePath]) {
+            return;
+        }
+
+        this.counter += 1;
+        const mapFile = this.basePath + this.counter;
+        this.mappings[filePath] = mapFile;
+        fs.writeFileSync(mapFile, sourceText, 'utf8');
+    }
+
+    getSource(filePath) {
+        const mapFile = this.mappings[filePath];
+        if (!mapFile) {
+            return null;
+        }
+
+        return fs.readFileSync(mapFile, 'utf8');
+    }
+
+    dispose() {
+        this.mappings = [];
+        rimraf.sync(path.dirname(this.basePath));
+    }
+}
+
+module.exports = {
+    create(type = 'memory', opts = {}) {
+        if (type.toLowerCase() === 'file') {
+            return new FileStore(opts);
+        }
+
+        return new MemoryStore(opts);
+    }
+};