fix(js): detect TypeScript transformers beyond ts-jest

codeflash/languages/javascript/test_runner.py

@@ -219,6 +219,55 @@ def _has_ts_jest_dependency(project_root: Path) -> bool:
         return False
 
 
+def _detect_typescript_transformer(project_root: Path) -> tuple[str | None, str]:
+    package_json = project_root / "package.json"
+    if not package_json.exists():
+        return (None, "")
+
+    try:
+        content = json.loads(package_json.read_text(encoding="utf-8"))
+        deps = {**content.get("dependencies", {}), **content.get("devDependencies", {})}
+
+        # Check for various TypeScript transformers in order of preference
+        if "ts-jest" in deps:
+            config = """
+  // Ensure TypeScript files are transformed using ts-jest
+  transform: {
+    '^.+\\\\.(ts|tsx)$': ['ts-jest', { isolatedModules: true }],
+    // Use ts-jest for JS files in ESM packages too
+    '^.+\\\\.js$': ['ts-jest', { isolatedModules: true }],
+  },"""
+            return ("ts-jest", config)
+
+        if "@swc/jest" in deps:
+            config = """
+  // Ensure TypeScript files are transformed using @swc/jest
+  transform: {
+    '^.+\\\\.(ts|tsx)$': '@swc/jest',
+  },"""
+            return ("@swc/jest", config)
+
+        if "babel-jest" in deps and "@babel/preset-typescript" in deps:
+            config = """
+  // Ensure TypeScript files are transformed using babel-jest
+  transform: {
+    '^.+\\\\.(ts|tsx)$': 'babel-jest',
+  },"""
+            return ("babel-jest", config)
+
+        if "esbuild-jest" in deps:
+            config = """
+  // Ensure TypeScript files are transformed using esbuild-jest
+  transform: {
+    '^.+\\\\.(ts|tsx)$': 'esbuild-jest',
+  },"""
+            return ("esbuild-jest", config)
+
+        return (None, "")
+    except (json.JSONDecodeError, OSError):
+        return (None, "")
+
+
 def _create_codeflash_jest_config(
     project_root: Path, original_jest_config: Path | None, *, for_esm: bool = False
 ) -> Path | None:
@@ -278,21 +327,13 @@ def _create_codeflash_jest_config(
     ]
     esm_pattern = "|".join(esm_packages)
 
-    # Check if ts-jest is available in the project
-    has_ts_jest = _has_ts_jest_dependency(project_root)
+    # Detect TypeScript transformer in the project
+    transformer_name, transform_config = _detect_typescript_transformer(project_root)
 
-    # Build transform config only if ts-jest is available
-    if has_ts_jest:
-        transform_config = """
-  // Ensure TypeScript files are transformed using ts-jest
-  transform: {
-    '^.+\\\\.(ts|tsx)$': ['ts-jest', { isolatedModules: true }],
-    // Use ts-jest for JS files in ESM packages too
-    '^.+\\\\.js$': ['ts-jest', { isolatedModules: true }],
-  },"""
+    if transformer_name:
+        logger.debug(f"Detected TypeScript transformer: {transformer_name}")
     else:
-        transform_config = ""
-        logger.debug("ts-jest not found in project dependencies, skipping transform config")
+        logger.debug("No TypeScript transformer found in project dependencies")
 
     # Create a wrapper Jest config
     if original_jest_config:

tests/test_languages/test_typescript_transform_extraction.py

@@ -0,0 +1,87 @@
+from pathlib import Path
+
+
+class TestTypeScriptTransformExtraction:
+    def test_extracts_swc_transform_from_typescript_config(self, tmp_path: Path) -> None:
+        from codeflash.languages.javascript.test_runner import (
+            _create_codeflash_jest_config,
+            clear_created_config_files,
+        )
+
+        tmpdir_path = tmp_path.resolve()
+
+        # Create package.json without ts-jest (mimics budibase)
+        (tmpdir_path / "package.json").write_text(
+            '{"name": "test", "devDependencies": {"@swc/jest": "^0.2.0"}}', encoding="utf-8"
+        )
+
+        # Create jest.config.ts with @swc/jest transform (mimics budibase)
+        jest_config_content = """import { Config } from "jest"
+
+const config: Config = {
+  transform: {
+    "^.+\\\\.ts?$": "@swc/jest",
+  },
+}
+
+export default config
+"""
+        jest_config_path = tmpdir_path / "jest.config.ts"
+        jest_config_path.write_text(jest_config_content, encoding="utf-8")
+
+        clear_created_config_files()
+
+        result = _create_codeflash_jest_config(tmpdir_path, jest_config_path)
+
+        assert result is not None, "Should create a codeflash config"
+
+        generated_config = result.read_text(encoding="utf-8")
+
+        # The generated config MUST include a transform directive for TypeScript files
+        assert "transform" in generated_config, f"Generated config must include transform directive. Got:\n{generated_config}"
+
+        # Verify it can actually transform TypeScript files (.ts extension)
+        assert (
+            "@swc/jest" in generated_config or "ts-jest" in generated_config or '"^.+\\\\.ts' in generated_config
+        ), f"Generated config must include TypeScript file transformation. Got:\n{generated_config}"
+
+        clear_created_config_files()
+
+    def test_extracts_ts_jest_transform_from_typescript_config(self, tmp_path: Path) -> None:
+        from codeflash.languages.javascript.test_runner import (
+            _create_codeflash_jest_config,
+            clear_created_config_files,
+        )
+
+        tmpdir_path = tmp_path.resolve()
+
+        # Create package.json with ts-jest
+        (tmpdir_path / "package.json").write_text(
+            '{"name": "test", "devDependencies": {"ts-jest": "^29.0.0"}}', encoding="utf-8"
+        )
+
+        # Create jest.config.ts with ts-jest transform
+        jest_config_content = """import { Config } from "jest"
+
+const config: Config = {
+  transform: {
+    "^.+\\\\.(ts|tsx)$": "ts-jest",
+  },
+}
+
+export default config
+"""
+        jest_config_path = tmpdir_path / "jest.config.ts"
+        jest_config_path.write_text(jest_config_content, encoding="utf-8")
+
+        clear_created_config_files()
+
+        result = _create_codeflash_jest_config(tmpdir_path, jest_config_path)
+
+        assert result is not None, "Should create a codeflash config"
+
+        generated_config = result.read_text(encoding="utf-8")
+
+        assert "ts-jest" in generated_config, f"Generated config should include ts-jest transform. Got:\n{generated_config}"
+
+        clear_created_config_files()