Fix JS CI regressions from CLI follow-up

Author: mohamedashrraf222

codeflash/code_utils/formatter.py

@@ -60,6 +60,10 @@ def apply_formatter_cmds(
     for command in cmds:
         formatter_cmd_list = shlex.split(command, posix=os.name != "nt")
         formatter_cmd_list = [file_path.as_posix() if chunk == file_token else chunk for chunk in formatter_cmd_list]
+        if str(lang_support.language) in ("javascript", "typescript"):
+            from codeflash.languages.javascript.command_utils import resolve_node_command_list
+
+            formatter_cmd_list = resolve_node_command_list(formatter_cmd_list)
         try:
             result = subprocess.run(formatter_cmd_list, capture_output=True, check=False)
             if result.returncode == 0:

codeflash/discovery/functions_to_optimize.py

@@ -1,7 +1,6 @@
 from __future__ import annotations
 
 import ast
-import contextlib
 import os
 import random
 import warnings

codeflash/verification/verifier.py

@@ -61,10 +61,11 @@ def generate_tests(
 
         source_file_abs = source_file.resolve().with_suffix("")
         test_dir_abs = test_path.resolve().parent
-        # Compute relative path from test directory to source file
-        rel_import_path = os.path.relpath(str(source_file_abs), str(test_dir_abs))
+        # Compute relative path from test directory to source file.
+        # JavaScript import specifiers must always use forward slashes, even on Windows.
+        rel_import_path = os.path.relpath(str(source_file_abs), str(test_dir_abs)).replace("\\", "/")
         # Ensure path starts with ./ or ../ for JavaScript/TypeScript imports
-        if not rel_import_path.startswith("../"):
+        if not rel_import_path.startswith(("../", "./")):
             rel_import_path = f"./{rel_import_path}"
         # ESM requires explicit file extensions in import specifiers.
         # TypeScript ESM also uses .js extensions (TS resolves .js → .ts).

tests/languages/javascript/test_vitest_runner.py

@@ -16,6 +16,10 @@
 )
 
 
+def command_name(command: str) -> str:
+    return Path(command).stem.lower()
+
+
 class TestFindVitestProjectRoot:
     """Tests for _find_vitest_project_root function."""
 
@@ -96,9 +100,8 @@ def test_basic_command_structure(self) -> None:
 
             cmd = _build_vitest_behavioral_command([test_file], timeout=60)
 
-            assert cmd[0] == "npx"
-            assert cmd[1] == "vitest"
-            assert cmd[2] == "run"
+            assert command_name(cmd[0]) == "npx"
+            assert cmd[1:3] == ["vitest", "run"]
 
     def test_includes_reporter_flags(self) -> None:
         """Should include reporter flags for JUnit output."""
@@ -174,9 +177,8 @@ def test_basic_command_structure(self) -> None:
 
             cmd = _build_vitest_benchmarking_command([test_file], timeout=60)
 
-            assert cmd[0] == "npx"
-            assert cmd[1] == "vitest"
-            assert cmd[2] == "run"
+            assert command_name(cmd[0]) == "npx"
+            assert cmd[1:3] == ["vitest", "run"]
 
     def test_includes_serial_execution(self) -> None:
         """Should include serial execution for consistent benchmarking."""
@@ -202,7 +204,8 @@ def test_vitest_uses_run_subcommand(self) -> None:
 
             vitest_cmd = _build_vitest_behavioral_command([test_file], timeout=60)
 
-            assert vitest_cmd[0:3] == ["npx", "vitest", "run"]
+            assert command_name(vitest_cmd[0]) == "npx"
+            assert vitest_cmd[1:3] == ["vitest", "run"]
 
     def test_vitest_uses_hyphenated_timeout(self) -> None:
         """Vitest uses --test-timeout, Jest uses --testTimeout (camelCase)."""

tests/test_formatter.py

@@ -6,10 +6,10 @@
 import pytest
 
 from codeflash.code_utils.config_parser import parse_config_file
-from codeflash.code_utils.formatter import format_code, format_generated_code, sort_imports
+from codeflash.code_utils.formatter import apply_formatter_cmds, format_code, format_generated_code, sort_imports
 from codeflash.discovery.functions_to_optimize import FunctionToOptimize
-from codeflash.models.models import CodeString, CodeStringsMarkdown
 from codeflash.languages.function_optimizer import FunctionOptimizer
+from codeflash.models.models import CodeString, CodeStringsMarkdown
 from codeflash.verification.verification_utils import TestConfig
 
 
@@ -1394,6 +1394,30 @@ def test_format_generated_code_unicode():
     assert "Hello, 世界! 🌍" in result
 
 
+def test_apply_formatter_cmds_resolves_node_wrappers_for_javascript(tmp_path: Path):
+    """JavaScript formatter commands should resolve npx/npm wrappers before subprocess execution."""
+    from unittest.mock import MagicMock, patch
+
+    js_file = tmp_path / "test.js"
+    js_file.write_text("const value = 1;\n", encoding="utf-8")
+    resolved_cmd = [r"C:\nvm4w\nodejs\npx.cmd", "prettier", "--write", js_file.as_posix()]
+
+    with (
+        patch(
+            "codeflash.languages.javascript.command_utils.resolve_node_command_list", return_value=resolved_cmd
+        ) as mock_resolve,
+        patch("codeflash.code_utils.formatter.subprocess.run", return_value=MagicMock(returncode=0)) as mock_run,
+    ):
+        _, formatted_code, changed = apply_formatter_cmds(
+            ["npx prettier --write $file"], js_file, test_dir_str=None, print_status=False
+        )
+
+    mock_resolve.assert_called_once_with(["npx", "prettier", "--write", js_file.as_posix()])
+    mock_run.assert_called_once_with(resolved_cmd, capture_output=True, check=False)
+    assert changed is True
+    assert formatted_code == js_file.read_text(encoding="utf-8")
+
+
 def test_format_generated_code_uses_correct_extension_for_javascript():
     """Test that format_generated_code creates temp files with .js extension for JavaScript code."""
     from unittest.mock import patch

tests/test_init_javascript.py

@@ -1,6 +1,7 @@
 """Tests for JavaScript/TypeScript project initialization and package manager detection."""
 
 import json
+import tempfile
 from pathlib import Path
 from unittest.mock import patch
 
@@ -17,9 +18,15 @@
 
 
 @pytest.fixture
-def tmp_project(tmp_path: Path) -> Path:
-    """Create a temporary project directory."""
-    return tmp_path
+def tmp_project() -> Path:
+    """Create a temporary project directory with a deterministic parent chain."""
+    with tempfile.TemporaryDirectory(dir=Path.cwd()) as tmp_dir:
+        yield Path(tmp_dir)
+
+
+def assert_install_command(actual: list[str], executable: str, expected_args: list[str]) -> None:
+    assert Path(actual[0]).stem.lower() == executable
+    assert actual[1:] == expected_args
 
 
 class TestDetermineJsPackageManager:
@@ -206,7 +213,7 @@ def test_npm_install_command(self, tmp_project: Path) -> None:
 
         result = get_package_install_command(tmp_project, "codeflash", dev=True)
 
-        assert result == ["npm", "install", "codeflash", "--save-dev"]
+        assert_install_command(result, "npm", ["install", "codeflash", "--save-dev"])
 
     def test_npm_install_command_non_dev(self, tmp_project: Path) -> None:
         """Should return npm install command without --save-dev when dev=False."""
@@ -215,7 +222,7 @@ def test_npm_install_command_non_dev(self, tmp_project: Path) -> None:
 
         result = get_package_install_command(tmp_project, "codeflash", dev=False)
 
-        assert result == ["npm", "install", "codeflash"]
+        assert_install_command(result, "npm", ["install", "codeflash"])
 
     def test_pnpm_add_command(self, tmp_project: Path) -> None:
         """Should return pnpm add command for pnpm projects."""
@@ -224,7 +231,7 @@ def test_pnpm_add_command(self, tmp_project: Path) -> None:
 
         result = get_package_install_command(tmp_project, "codeflash", dev=True)
 
-        assert result == ["pnpm", "add", "codeflash", "--save-dev"]
+        assert_install_command(result, "pnpm", ["add", "codeflash", "--save-dev"])
 
     def test_pnpm_add_command_non_dev(self, tmp_project: Path) -> None:
         """Should return pnpm add command without --save-dev when dev=False."""
@@ -233,7 +240,7 @@ def test_pnpm_add_command_non_dev(self, tmp_project: Path) -> None:
 
         result = get_package_install_command(tmp_project, "codeflash", dev=False)
 
-        assert result == ["pnpm", "add", "codeflash"]
+        assert_install_command(result, "pnpm", ["add", "codeflash"])
 
     def test_yarn_add_command(self, tmp_project: Path) -> None:
         """Should return yarn add command for yarn projects."""
@@ -242,7 +249,7 @@ def test_yarn_add_command(self, tmp_project: Path) -> None:
 
         result = get_package_install_command(tmp_project, "codeflash", dev=True)
 
-        assert result == ["yarn", "add", "codeflash", "--dev"]
+        assert_install_command(result, "yarn", ["add", "codeflash", "--dev"])
 
     def test_yarn_add_command_non_dev(self, tmp_project: Path) -> None:
         """Should return yarn add command without --dev when dev=False."""
@@ -251,7 +258,7 @@ def test_yarn_add_command_non_dev(self, tmp_project: Path) -> None:
 
         result = get_package_install_command(tmp_project, "codeflash", dev=False)
 
-        assert result == ["yarn", "add", "codeflash"]
+        assert_install_command(result, "yarn", ["add", "codeflash"])
 
     def test_bun_add_command(self, tmp_project: Path) -> None:
         """Should return bun add command for bun projects."""
@@ -260,7 +267,7 @@ def test_bun_add_command(self, tmp_project: Path) -> None:
 
         result = get_package_install_command(tmp_project, "codeflash", dev=True)
 
-        assert result == ["bun", "add", "codeflash", "--dev"]
+        assert_install_command(result, "bun", ["add", "codeflash", "--dev"])
 
     def test_bun_add_command_non_dev(self, tmp_project: Path) -> None:
         """Should return bun add command without --dev when dev=False."""
@@ -269,14 +276,14 @@ def test_bun_add_command_non_dev(self, tmp_project: Path) -> None:
 
         result = get_package_install_command(tmp_project, "codeflash", dev=False)
 
-        assert result == ["bun", "add", "codeflash"]
+        assert_install_command(result, "bun", ["add", "codeflash"])
 
     def test_defaults_to_npm_for_unknown(self, tmp_project: Path) -> None:
         """Should default to npm for unknown package manager."""
         # No lockfile, no package.json - unknown package manager
         result = get_package_install_command(tmp_project, "codeflash", dev=True)
 
-        assert result == ["npm", "install", "codeflash", "--save-dev"]
+        assert_install_command(result, "npm", ["install", "codeflash", "--save-dev"])
 
     def test_different_package_name(self, tmp_project: Path) -> None:
         """Should work with different package names."""
@@ -285,7 +292,7 @@ def test_different_package_name(self, tmp_project: Path) -> None:
 
         result = get_package_install_command(tmp_project, "typescript", dev=True)
 
-        assert result == ["pnpm", "add", "typescript", "--save-dev"]
+        assert_install_command(result, "pnpm", ["add", "typescript", "--save-dev"])
 
 
 class TestShouldModifySkipConfirm:

tests/test_languages/test_javascript_requirements.py

@@ -4,7 +4,7 @@
 """
 
 import json
-from pathlib import Path
+from pathlib import Path, PureWindowsPath
 from unittest.mock import MagicMock, patch
 
 import pytest
@@ -15,6 +15,12 @@
 class TestVerifyRequirements:
     """Tests for JavaScriptSupport.verify_requirements()."""
 
+    @staticmethod
+    def _command_name(command: str) -> str:
+        if "\\" in command:
+            return PureWindowsPath(command).stem.lower()
+        return Path(command).stem.lower()
+
     @pytest.fixture
     def js_support(self):
         """Create a JavaScriptSupport instance."""
@@ -98,7 +104,7 @@ def test_verify_requirements_fails_without_npm(self, js_support, project_with_je
         """Test verification fails when npm is not available."""
 
         def mock_run_side_effect(cmd, **kwargs):
-            command_name = Path(cmd[0]).stem.lower()
+            command_name = self._command_name(cmd[0])
             if command_name == "node":
                 return MagicMock(returncode=0)
             if command_name == "npm":
@@ -113,13 +119,10 @@ def mock_run_side_effect(cmd, **kwargs):
             assert npm_error_found is True
 
     def test_verify_requirements_accepts_windows_cmd_wrappers(self, js_support, project_with_jest):
-        resolved_commands = {
-            "node": r"C:\nvm4w\nodejs\node.exe",
-            "npm": r"C:\nvm4w\nodejs\npm.cmd",
-        }
+        resolved_commands = {"node": r"C:\nvm4w\nodejs\node.exe", "npm": r"C:\nvm4w\nodejs\npm.cmd"}
 
         def mock_run_side_effect(cmd, **kwargs):
-            command_name = Path(cmd[0]).stem.lower()
+            command_name = self._command_name(cmd[0])
             assert cmd[0] == resolved_commands[command_name]
             return MagicMock(returncode=0)
 

tests/verification/test_verifier_path_handling.py

@@ -8,10 +8,13 @@
 """
 
 from pathlib import Path
+from unittest.mock import MagicMock, patch
 
 import pytest
 
 from codeflash.code_utils.code_utils import module_name_from_file_path
+from codeflash.models.function_types import FunctionToOptimize
+from codeflash.verification.verifier import generate_tests
 
 
 class TestVerifierPathHandling:
@@ -53,3 +56,54 @@ def test_module_name_from_file_path_with_fallback_succeeds(self) -> None:
 
         # After fallback, we should have a valid path
         assert test_module_path == "test_foo.test.ts"
+
+    def test_generate_tests_uses_forward_slashes_for_javascript_module_paths(self, tmp_path: Path) -> None:
+        """Generated JS import paths should stay valid on Windows by using forward slashes."""
+        project_root = tmp_path / "project"
+        source_dir = project_root / "src"
+        source_dir.mkdir(parents=True)
+
+        source_file = source_dir / "async_utils.js"
+        source_file.write_text("export async function processItemsSequential() {}", encoding="utf-8")
+
+        generated_tests_dir = source_dir / "__tests__" / "codeflash-generated"
+        generated_tests_dir.mkdir(parents=True)
+        test_path = generated_tests_dir / "test_processItemsSequential__unit_test_0.test.js"
+        test_perf_path = generated_tests_dir / "test_processItemsSequential__perf_test_0.test.js"
+
+        function_to_optimize = FunctionToOptimize(
+            function_name="processItemsSequential", file_path=source_file, language="javascript"
+        )
+        test_cfg = MagicMock(tests_project_rootdir=project_root / "tests", test_framework="jest")
+        ai_client = MagicMock()
+        ai_client.generate_regression_tests.return_value = ("generated", "behavior", "perf", None)
+
+        mock_support = MagicMock()
+        mock_support.detect_module_system.return_value = "esm"
+        mock_support.language_version = None
+        mock_support.process_generated_test_strings.side_effect = lambda **kwargs: (
+            kwargs["generated_test_source"],
+            kwargs["instrumented_behavior_test_source"],
+            kwargs["instrumented_perf_test_source"],
+        )
+
+        with patch("codeflash.verification.verifier.current_language_support", return_value=mock_support):
+            result = generate_tests(
+                aiservice_client=ai_client,
+                source_code_being_tested=source_file.read_text(encoding="utf-8"),
+                function_to_optimize=function_to_optimize,
+                helper_function_names=[],
+                module_path=source_file,
+                test_cfg=test_cfg,
+                test_timeout=30,
+                function_trace_id="trace-id",
+                test_index=0,
+                test_path=test_path,
+                test_perf_path=test_perf_path,
+            )
+
+        assert result is not None
+        module_path = ai_client.generate_regression_tests.call_args.kwargs["module_path"]
+        assert module_path == "../../async_utils.js"
+        assert "\\" not in module_path
+        assert not module_path.startswith("./..")