feat: early exit on JS setup failures and introduce SetupError type

setup_test_config now returns bool so the optimizer aborts when JS
requirements (Node, npm, test framework) are missing instead of
silently continuing. Adds SetupError dataclass, fixes warning log to
print messages, and updates tests.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: mohammedahmed18

codeflash/languages/base.py

@@ -50,6 +50,12 @@ class IndexResult:
     error: bool
 
 
+@dataclass(frozen=True)
+class SetupError:
+    message: str
+    should_abort: bool
+
+
 @dataclass
 class HelperFunction:
     """A helper function that is a dependency of the target function.
@@ -725,8 +731,12 @@ def prepare_module(
         """Parse/validate a module before optimization."""
         ...
 
-    def setup_test_config(self, test_cfg: TestConfig, file_path: Path, current_worktree: Path | None = None) -> None:
-        """One-time project setup after language detection. Default: no-op."""
+    def setup_test_config(self, test_cfg: TestConfig, file_path: Path, current_worktree: Path | None = None) -> bool:
+        """One-time project setup after language detection. Default: no-op.
+
+        Returns True if the project is valid for optimization, False otherwise.
+        """
+        return True
 
     def adjust_test_config_for_discovery(self, test_cfg: TestConfig) -> None:
         """Adjust test config before test discovery. Default: no-op."""

codeflash/languages/java/support.py

@@ -403,11 +403,12 @@ def load_coverage(
     ) -> None:
         return None
 
-    def setup_test_config(self, test_cfg: Any, file_path: Path, current_worktree: Path | None = None) -> None:
+    def setup_test_config(self, test_cfg: Any, file_path: Path, current_worktree: Path | None = None) -> bool:
         """Detect test framework from project build config (pom.xml / build.gradle)."""
         config = detect_java_project(test_cfg.project_root_path)
         if config is not None:
             self._test_framework = config.test_framework
+        return True
 
     def adjust_test_config_for_discovery(self, test_cfg: Any) -> None:
         """Adjust test config before test discovery for Java.

codeflash/languages/javascript/optimizer.py

@@ -3,6 +3,7 @@
 from typing import TYPE_CHECKING
 
 from codeflash.cli_cmds.console import logger
+from codeflash.languages.base import SetupError
 from codeflash.models.models import ValidCode
 
 if TYPE_CHECKING:
@@ -25,19 +26,21 @@ def prepare_javascript_module(
     return validated_original_code, None
 
 
-def verify_js_requirements(test_cfg: TestConfig) -> None:
+def verify_js_requirements(test_cfg: TestConfig) -> list[SetupError]:
     """Verify JavaScript/TypeScript requirements before optimization.
 
     Checks that Node.js, npm, and the test framework are available.
     Logs warnings if requirements are not met but does not abort.
+
+    Returns: List of setup errors if requirements are not met, empty list otherwise.
     """
     from codeflash.languages import get_language_support
     from codeflash.languages.base import Language
     from codeflash.languages.test_framework import get_js_test_framework_or_default
 
     js_project_root = test_cfg.js_project_root
     if not js_project_root:
-        return
+        return [SetupError("JavaScript project root not found", should_abort=True)]
 
     try:
         js_support = get_language_support(Language.JAVASCRIPT)
@@ -47,6 +50,9 @@ def verify_js_requirements(test_cfg: TestConfig) -> None:
         if not success:
             logger.warning("JavaScript requirements check found issues:")
             for error in errors:
-                logger.warning(f"  - {error}")
+                logger.warning(f"  - {error.message}")
+            return errors
+        return []
     except Exception as e:
         logger.debug(f"Failed to verify JS requirements: {e}")
+        return [SetupError(str(e), should_abort=True)]

codeflash/languages/javascript/support.py

@@ -14,7 +14,15 @@
 
 from codeflash.code_utils.git_utils import git_root_dir, mirror_path
 from codeflash.discovery.functions_to_optimize import FunctionToOptimize
-from codeflash.languages.base import CodeContext, FunctionFilterCriteria, HelperFunction, Language, TestInfo, TestResult
+from codeflash.languages.base import (
+    CodeContext,
+    FunctionFilterCriteria,
+    HelperFunction,
+    Language,
+    SetupError,
+    TestInfo,
+    TestResult,
+)
 from codeflash.languages.javascript.treesitter import TreeSitterAnalyzer, TreeSitterLanguage, get_analyzer_for_file
 from codeflash.languages.registry import register_language
 from codeflash.models.models import FunctionParent
@@ -1950,7 +1958,7 @@ def prepare_module(
 
         return prepare_javascript_module(module_code, module_path)
 
-    def setup_test_config(self, test_cfg: TestConfig, file_path: Path, current_worktree: Path | None) -> None:
+    def setup_test_config(self, test_cfg: TestConfig, file_path: Path, current_worktree: Path | None) -> bool:
         from codeflash.languages.javascript.optimizer import verify_js_requirements
         from codeflash.languages.javascript.test_runner import find_node_project_root
 
@@ -1970,7 +1978,11 @@ def setup_test_config(self, test_cfg: TestConfig, file_path: Path, current_workt
                 original_root_node_modules = original_js_root / "node_modules"
                 if original_root_node_modules.exists() and not worktree_root_node_modules.exists():
                     worktree_root_node_modules.symlink_to(original_root_node_modules)
-        verify_js_requirements(test_cfg)
+        setup_errors = verify_js_requirements(test_cfg)
+        if any(e.should_abort for e in setup_errors):
+            return False
+
+        return True
 
     def adjust_test_config_for_discovery(self, test_cfg: TestConfig) -> None:
         test_cfg.tests_project_rootdir = test_cfg.tests_root
@@ -2216,7 +2228,7 @@ def get_module_path(self, source_file: Path, project_root: Path, tests_root: Pat
             rel_path = source_file.relative_to(project_root)
             return "../" + rel_path.with_suffix("").as_posix()
 
-    def verify_requirements(self, project_root: Path, test_framework: str = "jest") -> tuple[bool, list[str]]:
+    def verify_requirements(self, project_root: Path, test_framework: str = "jest") -> tuple[bool, list[SetupError]]:
         """Verify that all JavaScript requirements are met.
 
         Checks for:
@@ -2242,21 +2254,34 @@ def verify_requirements(self, project_root: Path, test_framework: str = "jest")
         try:
             result = subprocess.run(["node", "--version"], check=False, capture_output=True, text=True, timeout=10)
             if result.returncode != 0:
-                errors.append("Node.js is not installed. Please install Node.js 18+ from https://nodejs.org/")
+                errors.append(
+                    SetupError(
+                        "Node.js is not installed. Please install Node.js 18+ from https://nodejs.org/",
+                        should_abort=True,
+                    )
+                )
         except FileNotFoundError:
-            errors.append("Node.js is not installed. Please install Node.js 18+ from https://nodejs.org/")
+            errors.append(
+                SetupError(
+                    "Node.js is not installed. Please install Node.js 18+ from https://nodejs.org/", should_abort=True
+                )
+            )
         except Exception as e:
-            errors.append(f"Failed to check Node.js: {e}")
+            errors.append(SetupError(f"Failed to check Node.js: {e}", should_abort=True))
 
         # Check npm
         try:
             result = subprocess.run(["npm", "--version"], check=False, capture_output=True, text=True, timeout=10)
             if result.returncode != 0:
-                errors.append("npm is not available. Please ensure npm is installed with Node.js.")
+                errors.append(
+                    SetupError("npm is not available. Please ensure npm is installed with Node.js.", should_abort=True)
+                )
         except FileNotFoundError:
-            errors.append("npm is not available. Please ensure npm is installed with Node.js.")
+            errors.append(
+                SetupError("npm is not available. Please ensure npm is installed with Node.js.", should_abort=True)
+            )
         except Exception as e:
-            errors.append(f"Failed to check npm: {e}")
+            errors.append(SetupError(f"Failed to check npm: {e}", should_abort=True))
 
         # Check test framework is installed (with monorepo support)
         # Uses find_node_modules_with_package which searches up the directory tree
@@ -2270,12 +2295,17 @@ def verify_requirements(self, project_root: Path, test_framework: str = "jest")
             local_node_modules = project_root / "node_modules"
             if not local_node_modules.exists():
                 errors.append(
-                    f"node_modules not found in {project_root}. Please run 'npm install' to install dependencies."
+                    SetupError(
+                        f"node_modules not found in {project_root}. Please run 'npm install' to install dependencies.",
+                        should_abort=True,
+                    )
                 )
             else:
                 errors.append(
-                    f"{test_framework} is not installed. "
-                    f"Please run 'npm install --save-dev {test_framework}' to install it."
+                    SetupError(
+                        f"{test_framework} is not installed. Please run 'npm install --save-dev {test_framework}' to install it.",
+                        should_abort=True,
+                    )
                 )
 
         return len(errors) == 0, errors

codeflash/languages/python/support.py

@@ -1044,8 +1044,9 @@ def prepare_module(
 
     pytest_cmd: str = "pytest"
 
-    def setup_test_config(self, test_cfg: TestConfig, file_path: Path, current_worktree: Path | None = None) -> None:
+    def setup_test_config(self, test_cfg: TestConfig, file_path: Path, current_worktree: Path | None = None) -> bool:
         self.pytest_cmd = test_cfg.pytest_cmd or "pytest"
+        return True
 
     def pytest_cmd_tokens(self, is_posix: bool) -> list[str]:
         import shlex

codeflash/optimization/optimizer.py

@@ -526,7 +526,11 @@ def run(self) -> None:
                 if funcs and funcs[0].language:
                     set_current_language(funcs[0].language)
                     self.test_cfg.set_language(funcs[0].language)
-                    current_language_support().setup_test_config(self.test_cfg, file_path, self.current_worktree)
+                    if not current_language_support().setup_test_config(
+                        self.test_cfg, file_path, self.current_worktree
+                    ):
+                        logger.error("Project setup failed — aborting optimization. Check warnings above for details.")
+                        return
                     break
 
         if self.args.all:

tests/test_languages/test_javascript_requirements.py

@@ -91,7 +91,7 @@ def test_verify_requirements_fails_without_node(self, js_support, project_with_j
 
             assert success is False
             assert len(errors) >= 1
-            node_error_found = any("Node.js" in error for error in errors)
+            node_error_found = any("Node.js" in error.message for error in errors)
             assert node_error_found is True
 
     def test_verify_requirements_fails_without_npm(self, js_support, project_with_jest):
@@ -108,7 +108,7 @@ def mock_run_side_effect(cmd, **kwargs):
             success, errors = js_support.verify_requirements(project_with_jest, "jest")
 
             assert success is False
-            npm_error_found = any("npm" in error for error in errors)
+            npm_error_found = any("npm" in error.message for error in errors)
             assert npm_error_found is True
 
     def test_verify_requirements_fails_without_node_modules(self, js_support, project_without_node_modules):
@@ -120,11 +120,11 @@ def test_verify_requirements_fails_without_node_modules(self, js_support, projec
 
             assert success is False
             assert len(errors) == 1
-            expected_error = (
+            expected_message = (
                 f"node_modules not found in {project_without_node_modules}. "
                 f"Please run 'npm install' to install dependencies."
             )
-            assert errors[0] == expected_error
+            assert errors[0].message == expected_message
 
     def test_verify_requirements_fails_without_test_framework(self, js_support, project_without_jest):
         """Test verification fails when test framework is not installed."""
@@ -135,8 +135,8 @@ def test_verify_requirements_fails_without_test_framework(self, js_support, proj
 
             assert success is False
             assert len(errors) == 1
-            expected_error = "jest is not installed. Please run 'npm install --save-dev jest' to install it."
-            assert errors[0] == expected_error
+            expected_message = "jest is not installed. Please run 'npm install --save-dev jest' to install it."
+            assert errors[0].message == expected_message
 
     def test_verify_requirements_returns_multiple_errors(self, js_support, project_without_node_modules):
         """Test that multiple errors can be returned."""
@@ -148,7 +148,7 @@ def test_verify_requirements_returns_multiple_errors(self, js_support, project_w
             assert success is False
             assert len(errors) >= 2
             # Should have errors for Node.js, npm, and node_modules
-            error_text = " ".join(errors)
+            error_text = " ".join(e.message for e in errors)
             assert "Node.js" in error_text
             assert "npm" in error_text
 
@@ -161,8 +161,8 @@ def test_verify_requirements_vitest_not_installed(self, js_support, project_with
 
             assert success is False
             assert len(errors) == 1
-            expected_error = "vitest is not installed. Please run 'npm install --save-dev vitest' to install it."
-            assert errors[0] == expected_error
+            expected_message = "vitest is not installed. Please run 'npm install --save-dev vitest' to install it."
+            assert errors[0].message == expected_message
 
     def test_verify_requirements_jest_not_installed(self, js_support, project_with_vitest):
         """Test verification fails when Jest is requested but only Vitest is installed."""
@@ -173,8 +173,8 @@ def test_verify_requirements_jest_not_installed(self, js_support, project_with_v
 
             assert success is False
             assert len(errors) == 1
-            expected_error = "jest is not installed. Please run 'npm install --save-dev jest' to install it."
-            assert errors[0] == expected_error
+            expected_message = "jest is not installed. Please run 'npm install --save-dev jest' to install it."
+            assert errors[0].message == expected_message
 
 
 class TestVerifyRequirementsIntegration: