Improve where snapshots are stored (#1489)

* Allow users to configure the snapshot location
* Resolve the location through source-maps, in case the tests were precompiled into a build directory, e.g. via TypeScript

Author: impaler

docs/recipes/typescript.md

@@ -18,7 +18,8 @@ Create a [`tsconfig.json`](https://github.com/Microsoft/TypeScript/wiki/tsconfig
 {
 	"compilerOptions": {
 		"module": "commonjs",
-		"target": "es2015"
+		"target": "es2015",
+		"sourceMaps": true
 	}
 }
 ```

lib/cli.js

@@ -149,6 +149,7 @@ exports.run = () => {
 		timeout: conf.timeout,
 		concurrency: conf.concurrency ? parseInt(conf.concurrency, 10) : 0,
 		updateSnapshots: conf.updateSnapshots,
+		snapshotDir: conf.snapshotDir ? path.resolve(projectDir, conf.snapshotDir) : null,
 		color: conf.color
 	});
 

lib/main.js

@@ -13,7 +13,8 @@ const runner = new Runner({
 	match: opts.match,
 	projectDir: opts.projectDir,
 	serial: opts.serial,
-	updateSnapshots: opts.updateSnapshots
+	updateSnapshots: opts.updateSnapshots,
+	snapshotDir: opts.snapshotDir
 });
 
 worker.setRunner(runner);

lib/runner.js

@@ -52,6 +52,7 @@ class Runner extends EventEmitter {
 		this.projectDir = options.projectDir;
 		this.serial = options.serial;
 		this.updateSnapshots = options.updateSnapshots;
+		this.snapshotDir = options.snapshotDir;
 
 		this.hasStarted = false;
 		this.results = [];
@@ -184,6 +185,8 @@ class Runner extends EventEmitter {
 	compareTestSnapshot(options) {
 		if (!this.snapshots) {
 			this.snapshots = snapshotManager.load({
+				file: this.file,
+				fixedLocation: this.snapshotDir,
 				name: path.basename(this.file),
 				projectDir: this.projectDir,
 				relFile: path.relative(this.projectDir, this.file),

lib/snapshot-manager.js

@@ -11,6 +11,7 @@ const indentString = require('indent-string');
 const makeDir = require('make-dir');
 const md5Hex = require('md5-hex');
 const Buffer = require('safe-buffer').Buffer;
+const convertSourceMap = require('convert-source-map');
 
 const concordanceOptions = require('./concordance-options').snapshotManager;
 
@@ -355,8 +356,13 @@ class Manager {
 	}
 }
 
-function determineSnapshotDir(projectDir, testDir) {
-	const parts = new Set(path.relative(projectDir, testDir).split(path.sep));
+function determineSnapshotDir(options) {
+	const testDir = determineSourceMappedDir(options);
+	if (options.fixedLocation) {
+		const relativeTestLocation = path.relative(options.projectDir, testDir);
+		return path.join(options.fixedLocation, relativeTestLocation);
+	}
+	const parts = new Set(path.relative(options.projectDir, testDir).split(path.sep));
 	if (parts.has('__tests__')) {
 		return path.join(testDir, '__snapshots__');
 	} else if (parts.has('test') || parts.has('tests')) { // Accept tests, even though it's not in the default test patterns
@@ -365,8 +371,21 @@ function determineSnapshotDir(projectDir, testDir) {
 	return testDir;
 }
 
+function determineSourceMappedDir(options) {
+	const source = tryRead(options.file).toString();
+	const converter = convertSourceMap.fromSource(source) || convertSourceMap.fromMapFileSource(source, options.testDir);
+	if (converter) {
+		const map = converter.toObject();
+		const firstSource = `${map.sourceRoot || ''}${map.sources[0]}`;
+		const sourceFile = path.resolve(options.testDir, firstSource);
+		return path.dirname(sourceFile);
+	}
+
+	return options.testDir;
+}
+
 function load(options) {
-	const dir = determineSnapshotDir(options.projectDir, options.testDir);
+	const dir = determineSnapshotDir(options);
 	const reportFile = `${options.name}.md`;
 	const snapFile = `${options.name}.snap`;
 	const snapPath = path.join(dir, snapFile);

readme.md

@@ -1045,6 +1045,20 @@ You can then check your code. If the change was intentional you can use the `--u
 $ ava --update-snapshots
 ```
 
+You can specify a fixed location for storing the snapshot files in AVA's [`package.json` configuration](#configuration):
+
+```json
+{
+  "ava": {
+    "snapshotLocation": "custom-directory"
+  }
+}
+```
+
+The snapshot files will be saved in a directory structure that mirrors that of your test files.
+
+If you are running AVA against precompiled test files, AVA will try and use source maps to determine the location of the original files. Snapshots will be stored next to these files, following the same rules as if AVA had executed the original files directly. This is great if you're writing your tests in TypeScript (see our [TypeScript recipe](docs/recipes/typescript.md)).
+
 ### Skipping assertions
 
 Any assertion can be skipped using the `skip` modifier. Skipped assertions are still counted, so there is no need to change your planned assertion count.

test/assert.js

@@ -755,10 +755,12 @@ test('.snapshot()', t => {
 
 	const projectDir = path.join(__dirname, 'fixture');
 	const manager = snapshotManager.load({
-		projectDir,
-		testDir: projectDir,
+		file: __filename,
 		name: 'assert.js',
+		projectDir,
 		relFile: 'test/assert.js',
+		fixedLocation: null,
+		testDir: projectDir,
 		updating
 	});
 	const setup = title => {

test/cli.js

@@ -710,6 +710,83 @@ test('legacy snapshot files are reported to the console', t => {
 	});
 });
 
+test('snapshots infer their location from sourcemaps', t => {
+	t.plan(8);
+	const relativeFixtureDir = path.join('fixture/snapshots/test-sourcemaps');
+	const snapDirStructure = [
+		'src',
+		'src/test/snapshots',
+		'src/feature/__tests__/__snapshots__'
+	];
+	const snapFixtureFilePaths = snapDirStructure
+		.map(snapRelativeDir => {
+			const snapPath = path.join(__dirname, relativeFixtureDir, snapRelativeDir);
+			return [
+				path.join(snapPath, 'test.js.md'),
+				path.join(snapPath, 'test.js.snap')
+			];
+		})
+		.reduce((a, b) => a.concat(b), []);
+	const removeExistingSnapFixtureFiles = snapPath => {
+		try {
+			fs.unlinkSync(snapPath);
+		} catch (err) {
+			if (err.code !== 'ENOENT') {
+				throw err;
+			}
+		}
+	};
+	snapFixtureFilePaths.forEach(removeExistingSnapFixtureFiles);
+	const verifySnapFixtureFiles = relFilePath => {
+		t.true(fs.existsSync(relFilePath));
+	};
+	execCli([], {dirname: relativeFixtureDir}, (err, stdout, stderr) => {
+		t.ifError(err);
+		snapFixtureFilePaths.forEach(verifySnapFixtureFiles);
+		t.match(stderr, /6 passed/);
+		t.end();
+	});
+});
+
+test('snapshots resolved location from "snapshotDir" in AVA config', t => {
+	t.plan(8);
+	const relativeFixtureDir = 'fixture/snapshots/test-snapshot-location';
+	const snapDir = 'snapshot-fixtures';
+	const snapDirStructure = [
+		'src',
+		'src/feature',
+		'src/feature/nested-feature'
+	];
+	const snapFixtureFilePaths = snapDirStructure
+		.map(snapRelativeDir => {
+			const snapPath = path.join(__dirname, relativeFixtureDir, snapDir, snapRelativeDir);
+			return [
+				path.join(snapPath, 'test.js.md'),
+				path.join(snapPath, 'test.js.snap')
+			];
+		})
+		.reduce((a, b) => a.concat(b), []);
+	const removeExistingSnapFixtureFiles = snapPath => {
+		try {
+			fs.unlinkSync(snapPath);
+		} catch (err) {
+			if (err.code !== 'ENOENT') {
+				throw err;
+			}
+		}
+	};
+	snapFixtureFilePaths.forEach(removeExistingSnapFixtureFiles);
+	const verifySnapFixtureFiles = relFilePath => {
+		t.true(fs.existsSync(relFilePath));
+	};
+	execCli([], {dirname: relativeFixtureDir}, (err, stdout, stderr) => {
+		t.ifError(err);
+		snapFixtureFilePaths.forEach(verifySnapFixtureFiles);
+		t.match(stderr, /6 passed/);
+		t.end();
+	});
+});
+
 test('--no-color disables formatting colors', t => {
 	execCli(['--no-color', '--verbose', 'formatting-color.js'], {dirname: 'fixture'}, (err, stdout, stderr) => {
 		t.ok(err);

test/fixture/snapshots/test-snapshot-location/package.json

@@ -0,0 +1,8 @@
+{
+	"ava": {
+		"files": [
+			"src/**/*test.js"
+		],
+		"snapshotDir": "snapshot-fixtures"
+	}
+}

test/fixture/snapshots/test-snapshot-location/src/feature/nested-feature/test.js

@@ -0,0 +1,11 @@
+import test from '../../../../../../..';
+
+test('test nested feature title', t => {
+	t.snapshot({foo: 'bar'});
+
+	t.snapshot({answer: 42});
+});
+
+test('another nested feature test', t => {
+	t.snapshot(new Map());
+});

test/fixture/snapshots/test-snapshot-location/src/feature/test.js

@@ -0,0 +1,11 @@
+import test from '../../../../../..';
+
+test('test feature title', t => {
+	t.snapshot({foo: 'bar'});
+
+	t.snapshot({answer: 42});
+});
+
+test('another feature test', t => {
+	t.snapshot(new Map());
+});

test/fixture/snapshots/test-snapshot-location/src/test.js

@@ -0,0 +1,11 @@
+import test from '../../../../..';
+
+test('test title', t => {
+	t.snapshot({foo: 'bar'});
+
+	t.snapshot({answer: 42});
+});
+
+test('another test', t => {
+	t.snapshot(new Map());
+});

test/fixture/snapshots/test-sourcemaps/build/feature/__tests__/test.js

@@ -0,0 +1,7 @@
+{
+	"ava": {
+		"files": [
+			"build/**/*test.js"
+		]
+	}
+}

test/fixture/snapshots/test-sourcemaps/build/feature/__tests__/test.js.map

@@ -0,0 +1,11 @@
+import test from '../../../../../../..'
+
+test('feature test title', t => {
+	t.snapshot({foo: 'bar'});
+
+	t.snapshot({answer: 40});
+});
+
+test('another feature test', t => {
+	t.snapshot(new Map());
+});

test/fixture/snapshots/test-sourcemaps/build/test.js

@@ -0,0 +1,11 @@
+import test from '../../../../..';
+
+test('top level test title', t => {
+	t.snapshot({foo: 'bar'});
+
+	t.snapshot({answer: 42});
+});
+
+test('another top level test', t => {
+	t.snapshot(new Map());
+});

test/fixture/snapshots/test-sourcemaps/build/test.js.map

@@ -0,0 +1,11 @@
+import test from '../../../../../..';
+
+test('test title', t => {
+	t.snapshot({foo: 'bar'});
+
+	t.snapshot({answer: 43});
+});
+
+test('another test', t => {
+	t.snapshot(new Map());
+});

test/fixture/snapshots/test-sourcemaps/build/test/test.js

@@ -0,0 +1,11 @@
+{
+	"compilerOptions": {
+		"target": "es6",
+		"module": "commonjs",
+		"outDir": "build",
+		"sourceMap": true
+	},
+	"include": [
+		"src/**/*test.ts"
+	]
+}