fix(hooks): emit PostToolUse additional context

tests/hooks/post-tool-use-auto-update.test.mjs

@@ -0,0 +1,157 @@
+import { spawnSync } from 'node:child_process';
+import {
+  mkdirSync,
+  mkdtempSync,
+  readFileSync,
+  rmSync,
+  writeFileSync,
+} from 'node:fs';
+import { tmpdir } from 'node:os';
+import { dirname, join, resolve } from 'node:path';
+import { fileURLToPath } from 'node:url';
+import { describe, expect, it } from 'vitest';
+
+const __dirname = dirname(fileURLToPath(import.meta.url));
+const repoRoot = resolve(__dirname, '../..');
+const hookScript = join(
+  repoRoot,
+  'understand-anything-plugin',
+  'hooks',
+  'post-tool-use-auto-update.mjs',
+);
+const hooksConfig = JSON.parse(
+  readFileSync(
+    join(repoRoot, 'understand-anything-plugin', 'hooks', 'hooks.json'),
+    'utf8',
+  ),
+);
+
+function runHook({
+  command = 'git commit -m "test"',
+  autoUpdate = true,
+  configContents,
+  createConfig = true,
+  createGraph = true,
+  dataDirName = '.understand-anything',
+  input,
+  pluginRoot,
+} = {}) {
+  const projectRoot = mkdtempSync(join(tmpdir(), 'ua-post-tool-use-'));
+  const dataDir = join(projectRoot, dataDirName);
+  mkdirSync(dataDir);
+  if (createConfig) {
+    writeFileSync(
+      join(dataDir, 'config.json'),
+      configContents ?? JSON.stringify({ autoUpdate }),
+    );
+  }
+  if (createGraph) writeFileSync(join(dataDir, 'knowledge-graph.json'), '{}');
+
+  const resolvedPluginRoot = pluginRoot ?? join(projectRoot, 'plugin root');
+  const result = spawnSync(process.execPath, [hookScript], {
+    cwd: projectRoot,
+    input:
+      input ??
+      JSON.stringify({
+        tool_name: 'Bash',
+        tool_input: { command },
+      }),
+    env: { ...process.env, CLAUDE_PLUGIN_ROOT: resolvedPluginRoot },
+    encoding: 'utf8',
+  });
+
+  rmSync(projectRoot, { recursive: true, force: true });
+  return { ...result, pluginRoot: resolvedPluginRoot };
+}
+
+describe('PostToolUse auto-update hook', () => {
+  it('is registered as the Bash PostToolUse handler', () => {
+    const registration = hooksConfig.hooks.PostToolUse[0];
+
+    expect(registration.matcher).toBe('Bash');
+    expect(registration.hooks).toEqual([
+      {
+        type: 'command',
+        command:
+          'node "${CLAUDE_PLUGIN_ROOT}/hooks/post-tool-use-auto-update.mjs"',
+      },
+    ]);
+  });
+
+  it('injects the auto-update instruction as PostToolUse additional context', () => {
+    const result = runHook();
+    const output = JSON.parse(result.stdout);
+
+    expect(result.status).toBe(0);
+    expect(result.stderr).toBe('');
+    expect(output).toEqual({
+      hookSpecificOutput: {
+        hookEventName: 'PostToolUse',
+        additionalContext: expect.stringContaining(
+          '[understand-anything] Commit detected',
+        ),
+      },
+    });
+    expect(output.hookSpecificOutput.additionalContext).toContain(
+      `${result.pluginRoot}/hooks/auto-update-prompt.md`,
+    );
+  });
+
+  it.each(['commit', 'merge', 'cherry-pick', 'rebase'])(
+    'recognizes git %s as a graph-changing operation',
+    (operation) => {
+      const result = runHook({ command: `git ${operation} example` });
+
+      expect(result.status).toBe(0);
+      expect(
+        JSON.parse(result.stdout).hookSpecificOutput.hookEventName,
+      ).toBe('PostToolUse');
+    },
+  );
+
+  it('preserves Windows-style plugin paths as valid JSON', () => {
+    const pluginRoot = 'C:\\Users\\Example Person\\understand-anything';
+    const result = runHook({ pluginRoot });
+    const output = JSON.parse(result.stdout);
+
+    expect(output.hookSpecificOutput.additionalContext).toContain(
+      `${pluginRoot}/hooks/auto-update-prompt.md`,
+    );
+  });
+
+  it('supports the legacy .ua data directory', () => {
+    const result = runHook({ dataDirName: '.ua' });
+
+    expect(result.status).toBe(0);
+    expect(JSON.parse(result.stdout).hookSpecificOutput.hookEventName).toBe(
+      'PostToolUse',
+    );
+  });
+
+  it('stays silent for unrelated Bash commands', () => {
+    const result = runHook({ command: 'git status --short' });
+
+    expect(result.status).toBe(0);
+    expect(result.stdout).toBe('');
+  });
+
+  it('stays silent when automatic updates are disabled', () => {
+    const result = runHook({ autoUpdate: false });
+
+    expect(result.status).toBe(0);
+    expect(result.stdout).toBe('');
+  });
+
+  it.each([
+    ['malformed stdin', { input: '{not-json' }],
+    ['a missing config', { createConfig: false }],
+    ['a malformed config', { configContents: '{not-json' }],
+    ['a missing graph', { createGraph: false }],
+  ])('stays silent for %s', (_scenario, options) => {
+    const result = runHook(options);
+
+    expect(result.status).toBe(0);
+    expect(result.stderr).toBe('');
+    expect(result.stdout).toBe('');
+  });
+});

understand-anything-plugin/hooks/hooks.json

@@ -6,7 +6,7 @@
         "hooks": [
           {
             "type": "command",
-            "command": "UA_DIR=.understand-anything; [ -d \"$UA_DIR\" ] || UA_DIR=.ua; INPUT=$(cat); CMD=$(printf '%s' \"$INPUT\" | node -e \"let d='';process.stdin.on('data',c=>d+=c);process.stdin.on('end',()=>{try{process.stdout.write(JSON.parse(d).tool_input?.command||'')}catch{}})\" 2>/dev/null); printf '%s' \"$CMD\" | grep -qE 'git\\s+(commit|merge|cherry-pick|rebase)' && [ -f $UA_DIR/config.json ] && grep -q '\"autoUpdate\".*true' $UA_DIR/config.json && [ -f $UA_DIR/knowledge-graph.json ] && echo \"[understand-anything] Commit detected with auto-update enabled. You MUST read the file at ${CLAUDE_PLUGIN_ROOT}/hooks/auto-update-prompt.md and execute its instructions to incrementally update the knowledge graph. Do not ask the user for confirmation — just do it.\" || true"
+            "command": "node \"${CLAUDE_PLUGIN_ROOT}/hooks/post-tool-use-auto-update.mjs\""
           }
         ]
       }

understand-anything-plugin/hooks/post-tool-use-auto-update.mjs

@@ -0,0 +1,57 @@
+import { existsSync, readFileSync } from 'node:fs';
+
+const COMMIT_COMMAND = /git\s+(commit|merge|cherry-pick|rebase)/;
+
+function findDataDir() {
+  return existsSync('.understand-anything') ? '.understand-anything' : '.ua';
+}
+
+function autoUpdateEnabled(dataDir) {
+  try {
+    const config = JSON.parse(readFileSync(`${dataDir}/config.json`, 'utf8'));
+    return config.autoUpdate === true;
+  } catch {
+    return false;
+  }
+}
+
+async function readStdin() {
+  let input = '';
+  process.stdin.setEncoding('utf8');
+  for await (const chunk of process.stdin) input += chunk;
+  return input;
+}
+
+async function main() {
+  let payload;
+  try {
+    payload = JSON.parse(await readStdin());
+  } catch {
+    return;
+  }
+
+  const command = payload?.tool_input?.command;
+  if (typeof command !== 'string' || !COMMIT_COMMAND.test(command)) return;
+
+  const dataDir = findDataDir();
+  if (!autoUpdateEnabled(dataDir)) return;
+  if (!existsSync(`${dataDir}/knowledge-graph.json`)) return;
+
+  const pluginRoot = process.env.CLAUDE_PLUGIN_ROOT ?? '';
+  const additionalContext =
+    `[understand-anything] Commit detected with auto-update enabled. ` +
+    `You MUST read the file at ${pluginRoot}/hooks/auto-update-prompt.md ` +
+    'and execute its instructions to incrementally update the knowledge graph. ' +
+    'Do not ask the user for confirmation — just do it.';
+
+  process.stdout.write(
+    JSON.stringify({
+      hookSpecificOutput: {
+        hookEventName: 'PostToolUse',
+        additionalContext,
+      },
+    }),
+  );
+}
+
+await main();