fix: handle multi-project Jest configs for generated tests

Rocket.Chat uses jest.config.ts with a projects: [...] field containing
restrictive testMatch patterns that reject generated test files. Detects
multi-project configs and creates a flat single-project config so
generated tests can run without matching the project's patterns.

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

Author: Saga4

codeflash/languages/javascript/test_runner.py

@@ -333,12 +333,84 @@ def _create_codeflash_jest_config(
         return None
 
 
+def _is_multi_project_jest_config(config_path: Path) -> bool:
+    """Check if a Jest config file uses a multi-project setup (projects: [...]).
+
+    Multi-project Jest configs restrict test matching to each project's testMatch patterns,
+    which prevents codeflash-generated tests from being discovered since they use a
+    different naming convention (test_*.test.ts vs *.spec.ts).
+    """
+    if config_path is None or not config_path.exists():
+        return False
+    try:
+        content = config_path.read_text(encoding="utf-8")
+        # Look for "projects:" or "projects =" in the config — both TS and JS forms
+        import re
+
+        return bool(re.search(r"\bprojects\s*[=:]", content))
+    except Exception:
+        return False
+
+
+def _create_flat_jest_config_for_generated_tests(project_root: Path, original_config: Path) -> Path | None:
+    """Create a simple single-project Jest config for running codeflash-generated tests.
+
+    When a project uses a multi-project Jest config (projects: [...]), each project has its own
+    testMatch/testPathPattern. Generated tests (test_*.test.ts) don't match these patterns.
+    This function creates a flat config that inherits transform/preset settings but uses
+    a broad testMatch so generated tests can be discovered.
+    """
+    is_esm = _is_esm_project(project_root)
+    config_ext = ".cjs" if is_esm else ".js"
+    codeflash_config_path = original_config.parent / f"jest.codeflash.config{config_ext}"
+
+    # Check if it already exists
+    if codeflash_config_path.exists():
+        return codeflash_config_path
+    alt_ext = ".js" if is_esm else ".cjs"
+    alt_path = codeflash_config_path.with_suffix(alt_ext)
+    if alt_path.exists():
+        return alt_path
+
+    has_ts_jest = _has_ts_jest_dependency(project_root)
+
+    if has_ts_jest:
+        transform_block = """
+  transform: {
+    '^.+\\\\.(ts|tsx)$': ['ts-jest', { isolatedModules: true }],
+    '^.+\\\\.js$': ['ts-jest', { isolatedModules: true }],
+  },"""
+    else:
+        transform_block = ""
+
+    # Create a flat single-project config (no 'projects' array) with broad testMatch
+    jest_config_content = f"""// Auto-generated by codeflash — flat config for generated test files
+// This replaces the multi-project config so codeflash-generated tests can be discovered
+module.exports = {{
+  rootDir: '{project_root.as_posix()}',
+  testEnvironment: 'node',
+  testMatch: ['**/*.test.ts', '**/*.test.js', '**/*.test.tsx', '**/*.test.jsx', '**/*.spec.ts', '**/*.spec.js'],
+  testPathIgnorePatterns: ['/node_modules/', '/dist/'],{transform_block}
+  moduleFileExtensions: ['ts', 'tsx', 'js', 'jsx', 'json', 'node'],
+}};
+"""
+    try:
+        codeflash_config_path.write_text(jest_config_content)
+        _created_config_files.add(codeflash_config_path)
+        logger.info(f"Created flat Jest config for generated tests: {codeflash_config_path}")
+        return codeflash_config_path
+    except Exception as e:
+        logger.warning(f"Failed to create flat Jest config: {e}")
+        return None
+
+
 def _get_jest_config_for_project(project_root: Path) -> Path | None:
     """Get the appropriate Jest config for the project.
 
     If the project uses bundler moduleResolution, creates and returns a
     codeflash-compatible Jest config. Otherwise, returns the project's
-    existing Jest config.
+    existing Jest config. For multi-project Jest configs, creates a flat
+    single-project config so codeflash-generated tests can be discovered.
 
     Args:
         project_root: Root of the project.
@@ -360,6 +432,14 @@ def _get_jest_config_for_project(project_root: Path) -> Path | None:
         if codeflash_jest_config:
             return codeflash_jest_config
 
+    # Handle multi-project Jest configs (projects: [...]) — these restrict testMatch
+    # per-project and prevent generated tests from being discovered
+    if _is_multi_project_jest_config(original_jest_config):
+        logger.info("Detected multi-project Jest config — creating flat config for generated tests")
+        flat_config = _create_flat_jest_config_for_generated_tests(project_root, original_jest_config)
+        if flat_config:
+            return flat_config
+
     return original_jest_config