fix(#977): map ephemeral fnm multishell execPath to a stable fnm alias in normalizeNodePath (#992)

* fix(#977): map ephemeral fnm multishell execPath to a stable fnm alias in normalizeNodePath Closes #977 * chore(#977): backfill changeset pr number (992) --------- Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>
2026-06-10 11:16:13 -04:00
parent 972a41a528
commit 36b68ac81d
4 changed files with 233 additions and 3 deletions
--- a/tests/bug-977-fnm-multishell-path.test.cjs
+++ b/tests/bug-977-fnm-multishell-path.test.cjs
@@ -0,0 +1,190 @@
+'use strict';
+
+process.env.GSD_TEST_MODE = '1';
+
+/**
+ * Bug #977: `resolveNodeRunner()` bakes an ephemeral fnm multishell shim path
+ * (e.g. `C:/Users/u/AppData/Local/fnm_multishells/<pid>_<ts>/node.exe`) into
+ * managed `.js` hook commands. fnm cleans up these per-shell-session directories
+ * when the shell exits, so the captured path later points at nothing — every
+ * managed hook fails to spawn until reinstall.
+ *
+ * Fix: when `normalizeNodePath` detects a path matching the fnm multishell
+ * directory pattern (`fnm_multishells/<id>/node(\.exe)?$`), it probes a stable
+ * alias path derived from `FNM_DIR` or `APPDATA` env vars (with injected
+ * `existsSync` for testability) and returns the first that exists. Falls back to
+ * the raw execPath if no stable alias is found.
+ *
+ * All assertions go against exported function return values — no source-grep.
+ */
+
+const { test, describe } = require('node:test');
+const assert = require('node:assert/strict');
+const path = require('node:path');
+
+const INSTALL = require(path.join(__dirname, '..', 'bin', 'install.js'));
+const { normalizeNodePath, resolveNodeRunner } = INSTALL;
+
+// ─── Synthetic paths used across tests ───────────────────────────────────────
+
+const EPHEMERAL_FNM_WIN = 'C:/Users/u/AppData/Local/fnm_multishells/15600_1781041703752/node.exe';
+const EPHEMERAL_FNM_WIN_BACKSLASH = 'C:\\Users\\u\\AppData\\Local\\fnm_multishells\\15600_1781041703752\\node.exe';
+const FNM_DIR_WIN = 'C:/Users/u/AppData/Roaming/fnm';
+const APPDATA_WIN = 'C:/Users/u/AppData/Roaming';
+const STABLE_FNM_DIR_NODE = `${FNM_DIR_WIN}/aliases/default/node.exe`;
+const STABLE_APPDATA_NODE = `${APPDATA_WIN}/fnm/aliases/default/node.exe`;
+
+// ─── normalizeNodePath — fnm multishell ephemeral path → stable alias ────────
+
+describe('Bug #977: normalizeNodePath — fnm multishell path with FNM_DIR → stable alias', () => {
+  test('forward-slash Windows ephemeral path + FNM_DIR set + alias exists → stable FNM_DIR alias', () => {
+    const result = normalizeNodePath(EPHEMERAL_FNM_WIN, {
+      env: { FNM_DIR: FNM_DIR_WIN },
+      existsSync: p => p === STABLE_FNM_DIR_NODE,
+    });
+    assert.equal(
+      result,
+      STABLE_FNM_DIR_NODE,
+      `expected stable FNM_DIR alias, got: ${result}`,
+    );
+  });
+
+  test('backslash Windows ephemeral path + FNM_DIR set + alias exists → stable FNM_DIR alias', () => {
+    const result = normalizeNodePath(EPHEMERAL_FNM_WIN_BACKSLASH, {
+      env: { FNM_DIR: FNM_DIR_WIN },
+      existsSync: p => p === STABLE_FNM_DIR_NODE,
+    });
+    assert.equal(
+      result,
+      STABLE_FNM_DIR_NODE,
+      `expected stable FNM_DIR alias, got: ${result}`,
+    );
+  });
+
+  test('FNM_DIR alias does not exist → falls through to APPDATA alias → returns APPDATA alias', () => {
+    const result = normalizeNodePath(EPHEMERAL_FNM_WIN, {
+      env: { FNM_DIR: FNM_DIR_WIN, APPDATA: APPDATA_WIN },
+      existsSync: p => p === STABLE_APPDATA_NODE, // FNM_DIR alias absent, APPDATA alias present
+    });
+    assert.equal(
+      result,
+      STABLE_APPDATA_NODE,
+      `expected stable APPDATA alias, got: ${result}`,
+    );
+  });
+
+  test('no alias exists → returns raw execPath unchanged (graceful fallback)', () => {
+    const result = normalizeNodePath(EPHEMERAL_FNM_WIN, {
+      env: { FNM_DIR: FNM_DIR_WIN, APPDATA: APPDATA_WIN },
+      existsSync: () => false, // nothing exists
+    });
+    assert.equal(
+      result,
+      EPHEMERAL_FNM_WIN,
+      `expected raw execPath fallback, got: ${result}`,
+    );
+  });
+
+  test('no FNM_DIR or APPDATA in env → returns raw execPath unchanged', () => {
+    const result = normalizeNodePath(EPHEMERAL_FNM_WIN, {
+      env: {},
+      existsSync: () => false,
+    });
+    assert.equal(
+      result,
+      EPHEMERAL_FNM_WIN,
+      `expected raw execPath fallback, got: ${result}`,
+    );
+  });
+});
+
+// ─── normalizeNodePath — non-fnm paths are NOT affected by the new branch ────
+
+describe('Bug #977: normalizeNodePath — non-fnm paths are unaffected (no regression to existing behavior)', () => {
+  test('NVM path is unchanged', () => {
+    const nvm = '/Users/dev/.nvm/versions/node/v20.11.0/bin/node';
+    assert.equal(normalizeNodePath(nvm), nvm);
+  });
+
+  test('Intel Homebrew Cellar path still maps to stable symlink', () => {
+    assert.equal(
+      normalizeNodePath('/usr/local/Cellar/node/25.8.1/bin/node'),
+      '/usr/local/bin/node',
+    );
+  });
+
+  test('Apple Silicon Homebrew Cellar path still maps to stable symlink', () => {
+    assert.equal(
+      normalizeNodePath('/opt/homebrew/Cellar/node/25.8.1/bin/node'),
+      '/opt/homebrew/bin/node',
+    );
+  });
+
+  test('regular Windows nodejs path is unchanged', () => {
+    const win = 'C:\\Program Files\\nodejs\\node.exe';
+    assert.equal(normalizeNodePath(win), win);
+  });
+
+  test('empty string is returned as-is', () => {
+    assert.equal(normalizeNodePath(''), '');
+  });
+
+  test('null is returned as-is', () => {
+    assert.equal(normalizeNodePath(null), null);
+  });
+});
+
+// ─── normalizeNodePath — already-stable fnm alias path is not re-processed ───
+
+describe('Bug #977: normalizeNodePath — already-stable fnm alias path passes through unchanged', () => {
+  test('stable FNM_DIR alias path is returned as-is', () => {
+    assert.equal(
+      normalizeNodePath(STABLE_FNM_DIR_NODE),
+      STABLE_FNM_DIR_NODE,
+    );
+  });
+});
+
+// ─── normalizeNodePath — false-positive guard: non-numeric id must NOT remap ──
+
+describe('Bug #977: normalizeNodePath — non-ephemeral fnm_multishells path is not remapped', () => {
+  test('non-numeric id segment (e.g. custom-dir) returns raw execPath unchanged even when alias exists', () => {
+    const nonEphemeral = 'C:/Users/u/AppData/Local/fnm_multishells/custom-dir/node.exe';
+    const stableAlias = 'C:/Users/u/AppData/Roaming/fnm/aliases/default/node.exe';
+    const result = normalizeNodePath(nonEphemeral, {
+      env: { FNM_DIR: 'C:/Users/u/AppData/Roaming/fnm' },
+      // existsSync returns true for the alias to prove the regex — not the existsSync — is the guard
+      existsSync: p => p === stableAlias,
+    });
+    assert.equal(
+      result,
+      nonEphemeral,
+      `expected raw execPath (non-ephemeral id must not be remapped), got: ${result}`,
+    );
+  });
+});
+
+// ─── resolveNodeRunner — opts pass-through ────────────────────────────────────
+
+describe('Bug #977: resolveNodeRunner — passes opts through to normalizeNodePath', () => {
+  test('fnm multishell execPath is resolved to stable alias via injected opts', () => {
+    const orig = process.execPath;
+    try {
+      Object.defineProperty(process, 'execPath', {
+        value: EPHEMERAL_FNM_WIN,
+        configurable: true,
+      });
+      const runner = resolveNodeRunner({
+        env: { FNM_DIR: FNM_DIR_WIN },
+        existsSync: p => p === STABLE_FNM_DIR_NODE,
+      });
+      assert.equal(
+        runner,
+        JSON.stringify(STABLE_FNM_DIR_NODE),
+        `expected stable FNM_DIR alias quoted, got: ${runner}`,
+      );
+    } finally {
+      Object.defineProperty(process, 'execPath', { value: orig, configurable: true });
+    }
+  });
+});