gstack/test/gstack-paths.test.ts

import { describe, test, expect } from 'bun:test';
import { spawnSync } from 'child_process';
import * as path from 'path';

const ROOT = path.resolve(import.meta.dir, '..');
const BIN = path.join(ROOT, 'bin', 'gstack-paths');

// Invoke via `bash` rather than executing the shebang-script directly.
// On Windows, spawnSync(scriptPath, ...) goes through CreateProcess, which
// doesn't parse `#!/usr/bin/env bash`. Production usage always sources the
// helper from inside a bash block (`eval "$(~/.claude/skills/gstack/bin/gstack-paths)"`)
// so bash is always the executor — this matches that contract.
//
// USERPROFILE: '' is a Windows-specific override. Git Bash auto-populates
// HOME from USERPROFILE at shell startup if HOME is unset/empty, which
// silently breaks the "HOME unset" test scenarios. Clearing USERPROFILE
// alongside HOME prevents that auto-population on Windows runners.
function run(env: Record<string, string | undefined>): Record<string, string> {
  const result = spawnSync('bash', [BIN], {
    env: { PATH: process.env.PATH, USERPROFILE: '', ...env } as Record<string, string>,
    encoding: 'utf-8',
    timeout: 30_000,
  });
  if (result.status !== 0) {
    throw new Error(`gstack-paths failed (status ${result.status}): ${result.stderr}`);
  }
  const out: Record<string, string> = {};
  for (const line of result.stdout.split('\n')) {
    const eq = line.indexOf('=');
    if (eq > 0) out[line.slice(0, eq)] = line.slice(eq + 1);
  }
  return out;
}

describe('gstack-paths', () => {
  test('GSTACK_HOME wins over CLAUDE_PLUGIN_DATA and HOME', () => {
    const got = run({
      GSTACK_HOME: '/tmp/explicit-state',
      CLAUDE_PLUGIN_DATA: '/tmp/plugin-data',
      HOME: '/tmp/home',
    });
    expect(got.GSTACK_STATE_ROOT).toBe('/tmp/explicit-state');
  });

  test('CLAUDE_PLUGIN_DATA ignored when CLAUDE_PLUGIN_ROOT is absent or non-gstack', () => {
    // Without CLAUDE_PLUGIN_ROOT, falls through to HOME path.
    const noRoot = run({ CLAUDE_PLUGIN_DATA: '/tmp/plugin-data', HOME: '/tmp/home' });
    expect(noRoot.GSTACK_STATE_ROOT).toBe('/tmp/home/.gstack');

    // With a CLAUDE_PLUGIN_ROOT that doesn't contain "gstack" (e.g. the codex plugin),
    // still falls through to HOME path — this is the cross-plugin contamination scenario.
    const wrongRoot = run({
      CLAUDE_PLUGIN_DATA: '/tmp/codex-data',
      CLAUDE_PLUGIN_ROOT: '/tmp/openai-codex',
      HOME: '/tmp/home',
    });
    expect(wrongRoot.GSTACK_STATE_ROOT).toBe('/tmp/home/.gstack');
  });

  test('CLAUDE_PLUGIN_DATA respected when CLAUDE_PLUGIN_ROOT identifies gstack', () => {
    const got = run({
      CLAUDE_PLUGIN_DATA: '/tmp/gstack-plugin-data',
      CLAUDE_PLUGIN_ROOT: '/tmp/gstack-garrytan',
      HOME: '/tmp/home',
    });
    expect(got.GSTACK_STATE_ROOT).toBe('/tmp/gstack-plugin-data');
  });

  test('HOME-derived state root when GSTACK_HOME and CLAUDE_PLUGIN_DATA unset', () => {
    const got = run({ HOME: '/tmp/myhome' });
    expect(got.GSTACK_STATE_ROOT).toBe('/tmp/myhome/.gstack');
  });

  test('CWD fallback when HOME also unset (container env)', () => {
    // Skip on Windows: Git Bash auto-derives HOME from USERPROFILE,
    // HOMEDRIVE, and HOMEPATH at shell startup. Even with all three
    // cleared, bash falls back to /c/Users/<user>. The container env
    // (HOME genuinely unset) is unreachable on Windows runners. The bash
    // script's CWD fallback IS correct — exercised on Linux/Mac CI.
    if (process.platform === 'win32') return;
    const got = run({ HOME: '' });
    expect(got.GSTACK_STATE_ROOT).toBe('.gstack');
  });

  test('PLAN_ROOT chain: GSTACK_PLAN_DIR > CLAUDE_PLANS_DIR > HOME > CWD', () => {
    expect(run({ GSTACK_PLAN_DIR: '/tmp/explicit', HOME: '/h' }).PLAN_ROOT).toBe('/tmp/explicit');
    expect(run({ CLAUDE_PLANS_DIR: '/tmp/claude', HOME: '/h' }).PLAN_ROOT).toBe('/tmp/claude');
    expect(run({ HOME: '/tmp/myhome' }).PLAN_ROOT).toBe('/tmp/myhome/.claude/plans');
    // CWD fallback only verifiable on POSIX — Git Bash auto-populates HOME.
    if (process.platform !== 'win32') {
      expect(run({ HOME: '' }).PLAN_ROOT).toBe('.claude/plans');
    }
  });

  test('TMP_ROOT chain: TMPDIR > TMP > .gstack/tmp', () => {
    expect(run({ TMPDIR: '/tmp/x', HOME: '/h' }).TMP_ROOT).toBe('/tmp/x');
    expect(run({ TMP: '/tmp/y', HOME: '/h' }).TMP_ROOT).toBe('/tmp/y');
    expect(run({ HOME: '' }).TMP_ROOT).toBe('.gstack/tmp');
  });

  test('emits all three exports on every invocation', () => {
    const got = run({ HOME: '/tmp/h' });
    expect(got).toHaveProperty('GSTACK_STATE_ROOT');
    expect(got).toHaveProperty('PLAN_ROOT');
    expect(got).toHaveProperty('TMP_ROOT');
  });

  // Regression: values must survive `eval "$(gstack-paths)"`, which is the
  // documented calling convention. A bare `echo` emits an unquoted RHS, so eval
  // re-parses it: backslashes become escapes and spaces become word separators.
  // On Windows $TMP is always a backslash path, so every skill that then runs
  // mktemp "$TMP_ROOT/..." fails and the bash block dies before doing any work.
  // These run identically on POSIX — the values are just strings.
  function evalRoundTrip(env: Record<string, string | undefined>, varName: string): string {
    const result = spawnSync(
      'bash',
      ['-c', `eval "$(bash "$1")"; printf '%s' "\${${varName}}"`, 'sh', BIN],
      {
        env: { PATH: process.env.PATH, USERPROFILE: '', ...env } as Record<string, string>,
        encoding: 'utf-8',
        timeout: 30_000,
      },
    );
    if (result.status !== 0) {
      throw new Error(`eval round-trip failed (status ${result.status}): ${result.stderr}`);
    }
    return result.stdout;
  }

  // Values are POSIX-shaped on purpose: MSYS/Git Bash rewrites `C:\...` env
  // values to `/c/...` before bash sees them, so a literal Windows path would
  // assert the translation layer rather than the quoting. A backslash is a
  // backslash to eval either way, which is the behavior under test.
  test('eval round-trip preserves backslashes (#2374)', () => {
    // Skip on Windows: MSYS also rewrites backslashes to forward slashes in
    // env values, so a literal backslash cannot be injected through the
    // environment on a Git Bash runner. The escape-eating this guards against
    // is pure eval semantics, so exercising it on Linux/macOS CI is sufficient
    // — same reasoning as the HOME-unset skips above.
    if (process.platform === 'win32') return;
    const backslashed = '/tmp/back\\slash/dir';
    expect(evalRoundTrip({ TMPDIR: backslashed, HOME: '/h' }, 'TMP_ROOT')).toBe(backslashed);
  });

  test('eval round-trip preserves spaces (#2374)', () => {
    // Bare echo made eval word-split this, leaving the variable empty and
    // emitting `<second-word>: command not found`.
    const spaced = '/tmp/two words/dir';
    expect(evalRoundTrip({ TMPDIR: spaced, HOME: '/h' }, 'TMP_ROOT')).toBe(spaced);
  });

  test('eval round-trip preserves quotes, and leaves plain paths alone (#2374)', () => {
    expect(evalRoundTrip({ TMPDIR: "/tmp/o'brien", HOME: '/h' }, 'TMP_ROOT')).toBe("/tmp/o'brien");
    expect(evalRoundTrip({ GSTACK_HOME: '/tmp/state root' }, 'GSTACK_STATE_ROOT')).toBe(
      '/tmp/state root',
    );
    expect(evalRoundTrip({ HOME: '/tmp/myhome' }, 'PLAN_ROOT')).toBe('/tmp/myhome/.claude/plans');
  });

  test('output is shell-evalable: only KEY=VALUE lines, no extra prose', () => {
    const result = spawnSync('bash', [BIN], {
      env: { PATH: process.env.PATH, USERPROFILE: '', HOME: '/tmp/h' } as Record<string, string>,
      encoding: 'utf-8',
      timeout: 30_000,
    });
    const lines = result.stdout.split('\n').filter(Boolean);
    for (const line of lines) {
      expect(line).toMatch(/^[A-Z_]+=.*/);
    }
  });
});