test_runner: refactor snapshots to support multiple files in the same process

doc/api/test.md

@@ -3204,6 +3204,16 @@ test('top level test', (t) => {
 });
 ```
 
+### `context.filePath`
+
+<!-- YAML
+added: REPLACEME
+-->
+
+The absolute path of the test file that created the current test. If a test file
+imports additional modules that generate tests, the imported tests will return
+the path of the root test file.
+
 ### `context.fullName`
 
 <!-- YAML
@@ -3438,6 +3448,16 @@ An instance of `SuiteContext` is passed to each suite function in order to
 interact with the test runner. However, the `SuiteContext` constructor is not
 exposed as part of the API.
 
+### `context.filePath`
+
+<!-- YAML
+added: REPLACEME
+-->
+
+The absolute path of the test file that created the current suite. If a test
+file imports additional modules that generate suites, the imported suites will
+return the path of the root test file.
+
 ### `context.name`
 
 <!-- YAML

lib/internal/test_runner/harness.js

@@ -221,7 +221,7 @@ let globalRoot;
 let reportersSetup;
 function getGlobalRoot() {
  if (!globalRoot) {
- globalRoot = createTestTree();
+ globalRoot = createTestTree({ __proto__: null, entryFile: process.argv?.[1] });
  globalRoot.reporter.on('test:fail', (data) => {
  if (data.todo === undefined || data.todo === false) {
  process.exitCode = kGenericUserError;

lib/internal/test_runner/snapshot.js

@@ -58,50 +58,12 @@ function setDefaultSnapshotSerializers(serializers) {
  serializerFns = ArrayPrototypeSlice(serializers);
 }
 
-class SnapshotManager {
- constructor(entryFile, updateSnapshots) {
- this.entryFile = entryFile;
- this.snapshotFile = undefined;
+class SnapshotFile {
+ constructor(snapshotFile) {
+ this.snapshotFile = snapshotFile;
  this.snapshots = { __proto__: null };
  this.nameCounts = new SafeMap();
- // A manager instance will only read or write snapshot files based on the
- // updateSnapshots argument.
- this.loaded = updateSnapshots;
- this.updateSnapshots = updateSnapshots;
- }
-
- resolveSnapshotFile() {
- if (this.snapshotFile === undefined) {
- const resolved = resolveSnapshotPathFn(this.entryFile);
-
- if (typeof resolved !== 'string') {
- const err = new ERR_INVALID_STATE('Invalid snapshot filename.');
- err.filename = resolved;
- throw err;
- }
-
- this.snapshotFile = resolved;
- }
- }
-
- serialize(input, serializers = serializerFns) {
- try {
- let value = input;
-
- for (let i = 0; i < serializers.length; ++i) {
- const fn = serializers[i];
- value = fn(value);
- }
-
- return `\n${templateEscape(value)}\n`;
- } catch (err) {
- const error = new ERR_INVALID_STATE(
- 'The provided serializers did not generate a string.',
- );
- error.input = input;
- error.cause = err;
- throw error;
- }
+ this.loaded = false;
  }
 
  getSnapshot(id) {
@@ -122,12 +84,11 @@ class SnapshotManager {
 
  nextId(name) {
  const count = this.nameCounts.get(name) ?? 1;
-
  this.nameCounts.set(name, count + 1);
  return `${name} ${count}`;
  }
 
- readSnapshotFile() {
+ readFile() {
  if (this.loaded) {
  debug('skipping read of snapshot file');
  return;
@@ -164,12 +125,7 @@ class SnapshotManager {
  }
  }
 
- writeSnapshotFile() {
- if (!this.updateSnapshots) {
- debug('skipping write of snapshot file');
- return;
- }
-
+ writeFile() {
  try {
  const keys = ArrayPrototypeSort(ObjectKeys(this.snapshots));
  const snapshotStrings = ArrayPrototypeMap(keys, (key) => {
@@ -186,34 +142,87 @@ class SnapshotManager {
  throw error;
  }
  }
+}
+
+class SnapshotManager {
+ constructor(updateSnapshots) {
+ // A manager instance will only read or write snapshot files based on the
+ // updateSnapshots argument.
+ this.updateSnapshots = updateSnapshots;
+ this.cache = new SafeMap();
+ }
+
+ resolveSnapshotFile(entryFile) {
+ let snapshotFile = this.cache.get(entryFile);
+
+ if (snapshotFile === undefined) {
+ const resolved = resolveSnapshotPathFn(entryFile);
+
+ if (typeof resolved !== 'string') {
+ const err = new ERR_INVALID_STATE('Invalid snapshot filename.');
+ err.filename = resolved;
+ throw err;
+ }
+
+ snapshotFile = new SnapshotFile(resolved);
+ snapshotFile.loaded = this.updateSnapshots;
+ this.cache.set(entryFile, snapshotFile);
+ }
+
+ return snapshotFile;
+ }
+
+ serialize(input, serializers = serializerFns) {
+ try {
+ let value = input;
+
+ for (let i = 0; i < serializers.length; ++i) {
+ const fn = serializers[i];
+ value = fn(value);
+ }
+
+ return `\n${templateEscape(value)}\n`;
+ } catch (err) {
+ const error = new ERR_INVALID_STATE(
+ 'The provided serializers did not generate a string.',
+ );
+ error.input = input;
+ error.cause = err;
+ throw error;
+ }
+ }
+
+ writeSnapshotFiles() {
+ if (!this.updateSnapshots) {
+ debug('skipping write of snapshot files');
+ return;
+ }
+
+ this.cache.forEach((snapshotFile) => {
+ snapshotFile.writeFile();
+ });
+ }
 
  createAssert() {
  const manager = this;
 
  return function snapshotAssertion(actual, options = kEmptyObject) {
  emitExperimentalWarning(kExperimentalWarning);
- // Resolve the snapshot file here so that any resolution errors are
- // surfaced as early as possible.
- manager.resolveSnapshotFile();
-
- const { fullName } = this;
- const id = manager.nextId(fullName);
-
  validateObject(options, 'options');
-
  const {
  serializers = serializerFns,
  } = options;
-
  validateFunctionArray(serializers, 'options.serializers');
-
+ const { filePath, fullName } = this;
+ const snapshotFile = manager.resolveSnapshotFile(filePath);
  const value = manager.serialize(actual, serializers);
+ const id = snapshotFile.nextId(fullName);
 
  if (manager.updateSnapshots) {
- manager.setSnapshot(id, value);
+ snapshotFile.setSnapshot(id, value);
  } else {
- manager.readSnapshotFile();
- strictEqual(value, manager.getSnapshot(id));
+ snapshotFile.readFile();
+ strictEqual(value, snapshotFile.getSnapshot(id));
  }
  };
  }

lib/internal/test_runner/test.js

@@ -133,7 +133,7 @@ function lazyAssertObject(harness) {
  const { getOptionValue } = require('internal/options');
  if (getOptionValue('--experimental-test-snapshots')) {
  const { SnapshotManager } = require('internal/test_runner/snapshot');
- harness.snapshotManager = new SnapshotManager(kFilename, updateSnapshots);
+ harness.snapshotManager = new SnapshotManager(updateSnapshots);
  assertObj.set('snapshot', harness.snapshotManager.createAssert());
  }
  }
@@ -225,6 +225,10 @@ class TestContext {
  return this.#test.name;
  }
 
+ get filePath() {
+ return this.#test.entryFile;
+ }
+
  get fullName() {
  return getFullName(this.#test);
  }
@@ -343,6 +347,10 @@ class SuiteContext {
  return this.#suite.name;
  }
 
+ get filePath() {
+ return this.#suite.entryFile;
+ }
+
  get fullName() {
  return getFullName(this.#suite);
  }
@@ -357,7 +365,7 @@ class Test extends AsyncResource {
  super('Test');
 
  let { fn, name, parent } = options;
- const { concurrency, loc, only, timeout, todo, skip, signal, plan } = options;
+ const { concurrency, entryFile, loc, only, timeout, todo, skip, signal, plan } = options;
 
  if (typeof fn !== 'function') {
  fn = noop;
@@ -386,6 +394,7 @@ class Test extends AsyncResource {
  this.runOnlySubtests = this.only;
  this.childNumber = 0;
  this.timeout = kDefaultTimeout;
+ this.entryFile = entryFile;
  this.root = this;
  this.hooks = {
  __proto__: null,
@@ -406,6 +415,7 @@ class Test extends AsyncResource {
  this.runOnlySubtests = !this.only;
  this.childNumber = parent.subtests.length + 1;
  this.timeout = parent.timeout;
+ this.entryFile = parent.entryFile;
  this.root = parent.root;
  this.hooks = {
  __proto__: null,
@@ -967,7 +977,7 @@ class Test extends AsyncResource {
 
  // Call this harness.coverage() before collecting diagnostics, since failure to collect coverage is a diagnostic.
  const coverage = harness.coverage();
- harness.snapshotManager?.writeSnapshotFile();
+ harness.snapshotManager?.writeSnapshotFiles();
  for (let i = 0; i < diagnostics.length; i++) {
  reporter.diagnostic(nesting, loc, diagnostics[i]);
  }

test/fixtures/test-runner/snapshots/imported-tests.js

@@ -0,0 +1,8 @@
+'use strict';
+const { suite, test } = require('node:test');
+
+suite('imported suite', () => {
+ test('imported test', (t) => {
+ t.assert.snapshot({ foo: 1, bar: 2 });
+ });
+});

test/fixtures/test-runner/snapshots/unit.js

@@ -26,3 +26,5 @@ test('`${foo}`', async (t) => {
 test('escapes in `\\${foo}`\n', async (t) => {
  t.assert.snapshot('`\\${foo}`\n');
 });
+
+require('./imported-tests');