chore: import upstream snapshot with attribution

__tests__/include-ignored-config.test.ts

@@ -0,0 +1,144 @@
+/**
+ * `codegraph.json` `includeIgnored` loader (#970, #976 / #622, #699).
+ *
+ * Parsing, validation, and mtime-caching of the opt-in patterns that re-include
+ * gitignored directories for embedded-repo discovery. The behavioral end of this
+ * feature (scanDirectory / discoverEmbeddedRepoRoots / sync honoring the patterns)
+ * lives in `multi-repo-workspace.test.ts`; these are the loader unit tests,
+ * mirroring the `extensions` loader coverage in `extension-mapping.test.ts`.
+ *
+ * Invariant under test: every failure mode degrades to the zero-config default
+ * (empty patterns → `.gitignore` fully respected), never a throw.
+ */
+import { describe, it, expect, beforeEach, afterEach } from 'vitest';
+import * as fs from 'node:fs';
+import * as path from 'node:path';
+import * as os from 'node:os';
+import { loadIncludeIgnoredPatterns, loadExtensionOverrides, clearProjectConfigCache, addIncludeIgnoredPatterns } from '../src/project-config';
+
+describe('includeIgnored loader (codegraph.json)', () => {
+  let dir: string;
+  beforeEach(() => {
+    dir = fs.mkdtempSync(path.join(os.tmpdir(), 'cg-includeignored-'));
+    clearProjectConfigCache();
+  });
+  afterEach(() => {
+    clearProjectConfigCache();
+    fs.rmSync(dir, { recursive: true, force: true });
+  });
+  const writeConfig = (obj: unknown) =>
+    fs.writeFileSync(
+      path.join(dir, 'codegraph.json'),
+      typeof obj === 'string' ? obj : JSON.stringify(obj)
+    );
+
+  it('returns an empty list when there is no codegraph.json (the default)', () => {
+    expect(loadIncludeIgnoredPatterns(dir)).toEqual([]);
+  });
+
+  it('loads a well-formed pattern array', () => {
+    writeConfig({ includeIgnored: ['packages/', 'services/'] });
+    expect(loadIncludeIgnoredPatterns(dir)).toEqual(['packages/', 'services/']);
+  });
+
+  it('trims whitespace and drops blank / non-string entries', () => {
+    writeConfig({ includeIgnored: ['  packages/  ', '', '   ', 42, null, 'services/'] });
+    expect(loadIncludeIgnoredPatterns(dir)).toEqual(['packages/', 'services/']);
+  });
+
+  it('ignores a non-array includeIgnored value without throwing', () => {
+    writeConfig({ includeIgnored: 'packages/' });
+    expect(loadIncludeIgnoredPatterns(dir)).toEqual([]);
+  });
+
+  it('ignores malformed JSON without throwing', () => {
+    writeConfig('{ not: valid json ');
+    expect(loadIncludeIgnoredPatterns(dir)).toEqual([]);
+  });
+
+  it('returns [] when the field is absent but other config is present', () => {
+    writeConfig({ extensions: { '.foo': 'typescript' } });
+    expect(loadIncludeIgnoredPatterns(dir)).toEqual([]);
+  });
+
+  it('coexists with extensions in one file (shared single parse)', () => {
+    writeConfig({ extensions: { '.foo': 'typescript' }, includeIgnored: ['vendor/'] });
+    expect(loadExtensionOverrides(dir)).toEqual({ '.foo': 'typescript' });
+    expect(loadIncludeIgnoredPatterns(dir)).toEqual(['vendor/']);
+  });
+
+  it('picks up a changed config (mtime-invalidated cache)', () => {
+    writeConfig({ includeIgnored: ['packages/'] });
+    expect(loadIncludeIgnoredPatterns(dir)).toEqual(['packages/']);
+
+    writeConfig({ includeIgnored: ['services/'] });
+    // Force a distinct mtime in case the filesystem clock is coarse.
+    const future = new Date(Date.now() + 2000);
+    fs.utimesSync(path.join(dir, 'codegraph.json'), future, future);
+
+    expect(loadIncludeIgnoredPatterns(dir)).toEqual(['services/']);
+  });
+
+  it('drops the patterns again when the config file is removed', () => {
+    writeConfig({ includeIgnored: ['packages/'] });
+    expect(loadIncludeIgnoredPatterns(dir)).toEqual(['packages/']);
+
+    fs.rmSync(path.join(dir, 'codegraph.json'));
+    expect(loadIncludeIgnoredPatterns(dir)).toEqual([]);
+  });
+});
+
+describe('addIncludeIgnoredPatterns (codegraph.json writer, #1156)', () => {
+  let dir: string;
+  beforeEach(() => {
+    dir = fs.mkdtempSync(path.join(os.tmpdir(), 'cg-addincludeignored-'));
+    clearProjectConfigCache();
+  });
+  afterEach(() => {
+    clearProjectConfigCache();
+    fs.rmSync(dir, { recursive: true, force: true });
+  });
+  const readConfig = () => JSON.parse(fs.readFileSync(path.join(dir, 'codegraph.json'), 'utf-8'));
+
+  it('creates codegraph.json when none exists', () => {
+    expect(addIncludeIgnoredPatterns(dir, ['mtc-a/', 'mtc-b/'])).toBe(2);
+    expect(loadIncludeIgnoredPatterns(dir)).toEqual(['mtc-a/', 'mtc-b/']);
+  });
+
+  it('merges into an existing list, preserving other keys and de-duping', () => {
+    fs.writeFileSync(
+      path.join(dir, 'codegraph.json'),
+      JSON.stringify({ extensions: { '.foo': 'typescript' }, includeIgnored: ['mtc-a/'] }),
+    );
+    expect(addIncludeIgnoredPatterns(dir, ['mtc-a/', 'mtc-b/'])).toBe(1); // only mtc-b/ is new
+    const parsed = readConfig();
+    expect(parsed.includeIgnored).toEqual(['mtc-a/', 'mtc-b/']);
+    expect(parsed.extensions).toEqual({ '.foo': 'typescript' }); // untouched
+  });
+
+  it('is idempotent — re-adding the same patterns adds nothing', () => {
+    addIncludeIgnoredPatterns(dir, ['mtc-a/']);
+    expect(addIncludeIgnoredPatterns(dir, ['mtc-a/'])).toBe(0);
+    expect(loadIncludeIgnoredPatterns(dir)).toEqual(['mtc-a/']);
+  });
+
+  it('replaces a non-array includeIgnored value rather than crashing', () => {
+    fs.writeFileSync(path.join(dir, 'codegraph.json'), JSON.stringify({ includeIgnored: 'oops' }));
+    expect(addIncludeIgnoredPatterns(dir, ['mtc-a/'])).toBe(1);
+    expect(loadIncludeIgnoredPatterns(dir)).toEqual(['mtc-a/']);
+  });
+
+  it('refuses to clobber a malformed existing codegraph.json (throws, leaves file intact)', () => {
+    const bad = '{ not: valid json ';
+    fs.writeFileSync(path.join(dir, 'codegraph.json'), bad);
+    expect(() => addIncludeIgnoredPatterns(dir, ['mtc-a/'])).toThrow();
+    expect(fs.readFileSync(path.join(dir, 'codegraph.json'), 'utf-8')).toBe(bad);
+  });
+
+  it('writes pretty-printed, newline-terminated JSON', () => {
+    addIncludeIgnoredPatterns(dir, ['mtc-a/']);
+    const raw = fs.readFileSync(path.join(dir, 'codegraph.json'), 'utf-8');
+    expect(raw.endsWith('\n')).toBe(true);
+    expect(raw).toContain('\n  "includeIgnored"'); // 2-space indent
+  });
+});