Allow instrumentation of transformed files with weird file extensions

CHANGELOG.md

@@ -27,6 +27,7 @@
 - `[jest-snapshot]` Downgrade semver to v6 to support node 8 ([#9451](https://github.com/facebook/jest/pull/9451))
 - `[jest-snapshot]` Properly indent new snapshots in the presences of existing ones ([#9523](https://github.com/facebook/jest/pull/9523))
 - `[jest-transform]` Correct sourcemap behavior for transformed and instrumented code ([#9460](https://github.com/facebook/jest/pull/9460))
+- `[jest-transform]` Allow instrumentation of transformed files with weird file extensions ([#9589](https://github.com/facebook/jest/pull/9589))
 - `[pretty-format]` Export `OldPlugin` type ([#9491](https://github.com/facebook/jest/pull/9491))
 
 ### Chore & Maintenance

e2e/__tests__/__snapshots__/coverageHandlebars.test.ts.snap

@@ -0,0 +1,10 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`code coverage for Handlebars 1`] = `
+"-----------|---------|----------|---------|---------|-------------------
+File       | % Stmts | % Branch | % Funcs | % Lines | Uncovered Line #s 
+-----------|---------|----------|---------|---------|-------------------
+All files  |      75 |    66.67 |   66.67 |   66.67 |                   
+ greet.hbs |      75 |    66.67 |   66.67 |   66.67 | 10                
+-----------|---------|----------|---------|---------|-------------------"
+`;

e2e/__tests__/coverageHandlebars.test.ts

@@ -0,0 +1,33 @@
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates. All Rights Reserved.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+import {readFileSync} from 'fs';
+import * as path from 'path';
+import {cleanup, run} from '../Utils';
+import runJest from '../runJest';
+
+const dir = path.resolve(__dirname, '../coverage-handlebars');
+const coverageDir = path.join(dir, 'coverage');
+
+beforeAll(() => {
+  cleanup(coverageDir);
+});
+
+it('code coverage for Handlebars', () => {
+  run('yarn', dir);
+  const result = runJest(dir, ['--coverage', '--no-cache']);
+
+  expect(result.exitCode).toBe(0);
+  expect(result.stdout).toMatchSnapshot();
+
+  const coverageMapFile = path.join(coverageDir, 'coverage-final.json');
+  const coverageMap = JSON.parse(readFileSync(coverageMapFile, 'utf-8'));
+
+  expect(
+    Object.keys(coverageMap).map(filename => path.basename(filename)),
+  ).toEqual(['greet.hbs']);
+});

e2e/coverage-handlebars/__tests__/greet.js

@@ -0,0 +1,13 @@
+/*
+ * Copyright (c) Facebook, Inc. and its affiliates. All Rights Reserved.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+const greet = require('../greet.hbs');
+
+test('am', () => {
+  expect(greet({am: true, name: 'Joe'})).toEqual(
+    '<p>Good\n  morning\nJoe!</p>\n'
+  );
+});

e2e/coverage-handlebars/greet.hbs

@@ -0,0 +1,13 @@
+{{!
+ * Copyright (c) Facebook, Inc. and its affiliates. All Rights Reserved.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+}}
+<p>Good
+{{#if am}}
+  morning
+{{else}}
+  evening
+{{/if}}
+{{name}}!</p>

e2e/coverage-handlebars/package.json

@@ -0,0 +1,12 @@
+{
+  "jest": {
+    "transform": {
+      "\\.hbs$": "<rootDir>/transform-handlebars.js"
+    },
+    "testEnvironment": "node"
+  },
+  "dependencies": {
+    "handlebars": "^4.7.3",
+    "source-map": "^0.6.1"
+  }
+}

e2e/coverage-handlebars/transform-handlebars.js

@@ -0,0 +1,20 @@
+/*
+ * Copyright (c) Facebook, Inc. and its affiliates. All Rights Reserved.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+const Handlebars = require('handlebars/dist/cjs/handlebars.js');
+const {SourceMapConsumer, SourceNode} = require('source-map');
+
+exports.process = (code, filename) => {
+  const pc = Handlebars.precompile(code, {srcName: filename});
+  const out = new SourceNode(null, null, null, [
+    'const Handlebars = require("handlebars/dist/cjs/handlebars.runtime.js");\n',
+    'module.exports = Handlebars.template(',
+    SourceNode.fromStringWithSourceMap(pc.code, new SourceMapConsumer(pc.map)),
+    ');\n',
+  ]).toStringWithSourceMap();
+  return {code: out.code, map: out.map.toString()};
+};

e2e/coverage-handlebars/yarn.lock

@@ -0,0 +1,55 @@
+# THIS IS AN AUTOGENERATED FILE. DO NOT EDIT THIS FILE DIRECTLY.
+# yarn lockfile v1
+
+
+commander@~2.20.3:
+  version "2.20.3"
+  resolved "https://registry.yarnpkg.com/commander/-/commander-2.20.3.tgz#fd485e84c03eb4881c20722ba48035e8531aeb33"
+  integrity sha512-GpVkmM8vF2vQUkj2LvZmD35JxeJOLCwJ9cUkugyk2nuhbv3+mJvpLYYt+0+USMxE+oj+ey/lJEnhZw75x/OMcQ==
+
+handlebars@^4.7.3:
+  version "4.7.3"
+  resolved "https://registry.yarnpkg.com/handlebars/-/handlebars-4.7.3.tgz#8ece2797826886cf8082d1726ff21d2a022550ee"
+  integrity sha512-SRGwSYuNfx8DwHD/6InAPzD6RgeruWLT+B8e8a7gGs8FWgHzlExpTFMEq2IA6QpAfOClpKHy6+8IqTjeBCu6Kg==
+  dependencies:
+    neo-async "^2.6.0"
+    optimist "^0.6.1"
+    source-map "^0.6.1"
+  optionalDependencies:
+    uglify-js "^3.1.4"
+
+minimist@~0.0.1:
+  version "0.0.10"
+  resolved "https://registry.yarnpkg.com/minimist/-/minimist-0.0.10.tgz#de3f98543dbf96082be48ad1a0c7cda836301dcf"
+  integrity sha1-3j+YVD2/lggr5IrRoMfNqDYwHc8=
+
+neo-async@^2.6.0:
+  version "2.6.1"
+  resolved "https://registry.yarnpkg.com/neo-async/-/neo-async-2.6.1.tgz#ac27ada66167fa8849a6addd837f6b189ad2081c"
+  integrity sha512-iyam8fBuCUpWeKPGpaNMetEocMt364qkCsfL9JuhjXX6dRnguRVOfk2GZaDpPjcOKiiXCPINZC1GczQ7iTq3Zw==
+
+optimist@^0.6.1:
+  version "0.6.1"
+  resolved "https://registry.yarnpkg.com/optimist/-/optimist-0.6.1.tgz#da3ea74686fa21a19a111c326e90eb15a0196686"
+  integrity sha1-2j6nRob6IaGaERwybpDrFaAZZoY=
+  dependencies:
+    minimist "~0.0.1"
+    wordwrap "~0.0.2"
+
+source-map@^0.6.1, source-map@~0.6.1:
+  version "0.6.1"
+  resolved "https://registry.yarnpkg.com/source-map/-/source-map-0.6.1.tgz#74722af32e9614e9c287a8d0bbde48b5e2f1a263"
+  integrity sha512-UjgapumWlbMhkBgzT7Ykc5YXUT46F0iKu8SGXq0bcwP5dz/h0Plj6enJqjz1Zbq2l5WaqYnrVbwWOWMyF3F47g==
+
+uglify-js@^3.1.4:
+  version "3.8.0"
+  resolved "https://registry.yarnpkg.com/uglify-js/-/uglify-js-3.8.0.tgz#f3541ae97b2f048d7e7e3aa4f39fd8a1f5d7a805"
+  integrity sha512-ugNSTT8ierCsDHso2jkBHXYrU8Y5/fY2ZUprfrJUiD7YpuFvV4jODLFmb3h4btQjqr5Nh4TX4XtgDfCU1WdioQ==
+  dependencies:
+    commander "~2.20.3"
+    source-map "~0.6.1"
+
+wordwrap@~0.0.2:
+  version "0.0.3"
+  resolved "https://registry.yarnpkg.com/wordwrap/-/wordwrap-0.0.3.tgz#a3d5da6cd5c0bc0008d37234bbaf1bed63059107"
+  integrity sha1-o9XabNXAvAAI03I0u68b7WMFkQc=

packages/jest-transform/src/ScriptTransformer.ts

@@ -213,6 +213,7 @@ export default class ScriptTransformer {
             // files outside `cwd` will not be instrumented
             cwd: this._config.rootDir,
             exclude: [],
+            extension: false,
             // Needed for correct coverage as soon as we start storing a source map of the instrumented code
             inputSourceMap: input.map,
             useInlineSourceMaps: false,