fix looping with JS/TS

codeflash/languages/javascript/mocha_runner.py

@@ -536,7 +536,9 @@ def run_mocha_benchmarking_tests(
         )
         mocha_env["CODEFLASH_TEST_MODULE"] = test_module_path
 
-    total_timeout = max(120, (target_duration_ms // 1000) + 60, timeout or 120)
+    # Subprocess timeout: target_duration + 120s headroom for Mocha startup.
+    # capturePerf's time budget governs actual looping.
+    total_timeout = max(120, (target_duration_ms // 1000) + 120)
 
     logger.debug(f"Running Mocha benchmarking tests: {' '.join(mocha_cmd)}")
     logger.debug(

codeflash/languages/javascript/support.py

@@ -2372,9 +2372,12 @@ def run_behavioral_tests(
             candidate_index=candidate_index,
         )
 
-    # JavaScript/TypeScript benchmarking uses high max_loops like Python (100,000)
-    # The actual loop count is limited by target_duration_seconds, not max_loops
-    JS_BENCHMARKING_MAX_LOOPS = 100_000
+    # Max iterations per capturePerf call site.  Each iteration writes a ~200-byte
+    # timing marker to stdout.  The actual loop count is governed by the 10s time
+    # budget (CODEFLASH_PERF_TARGET_DURATION_MS) — this constant is just a ceiling.
+    # Python uses max_loops=250; JS iterations are lighter (no pytest overhead) so
+    # 1000 gives comparable statistical power while keeping stdout under 200 KB.
+    JS_BENCHMARKING_MAX_LOOPS = 1_000
 
     def run_benchmarking_tests(
         self,
@@ -2384,7 +2387,7 @@ def run_benchmarking_tests(
         timeout: int | None = None,
         project_root: Path | None = None,
         min_loops: int = 5,
-        max_loops: int = 100_000,
+        max_loops: int = 1_000,
         target_duration_seconds: float = 10.0,
         test_framework: str | None = None,
     ) -> tuple[Path, Any]:

codeflash/languages/javascript/test_runner.py

@@ -1025,9 +1025,9 @@ def run_jest_benchmarking_tests(
     if "--max-old-space-size" not in existing_node_options:
         jest_env["NODE_OPTIONS"] = f"{existing_node_options} --max-old-space-size=4096".strip()
 
-    # Total timeout for the entire benchmark run (longer than single-loop timeout)
-    # Account for startup overhead + target duration + buffer
-    total_timeout = max(120, (target_duration_ms // 1000) + 60, timeout or 120)
+    # Subprocess timeout: target_duration + 120s headroom for Jest startup
+    # and TS compilation.  capturePerf's time budget governs actual looping.
+    total_timeout = max(120, (target_duration_ms // 1000) + 120)
 
     logger.debug(f"Running Jest benchmarking tests with in-process loop runner: {' '.join(jest_cmd)}")
     logger.debug(

codeflash/languages/javascript/vitest_runner.py

@@ -616,8 +616,10 @@ def run_vitest_benchmarking_tests(
         vitest_env["CODEFLASH_TEST_MODULE"] = test_module_path
         logger.debug(f"[VITEST-BENCH] Set CODEFLASH_TEST_MODULE={test_module_path}")
 
-    # Total timeout for the entire benchmark run
-    total_timeout = max(120, (target_duration_ms // 1000) + 60, timeout or 120)
+    # Subprocess timeout: target_duration + 120s headroom for Vitest startup
+    # (TS compilation, module resolution).  The capturePerf time budget (10s default)
+    # governs actual looping; this is just a safety net for process-level hangs.
+    total_timeout = max(120, (target_duration_ms // 1000) + 120)
 
     logger.debug(f"[VITEST-BENCH] Running Vitest benchmarking tests: {' '.join(vitest_cmd)}")
     logger.debug(

codeflash/models/models.py

@@ -773,7 +773,13 @@ def get_src_code(self, test_path: Path) -> Optional[str]:
             test_src = test_path.read_text(encoding="utf-8")
             module_node = cst.parse_module(test_src)
         except Exception:
-            return None
+            # libcst can't parse non-Python files (JS/TS) — return a descriptive string
+            # so the code repair API receives a non-None test_src_code.
+            return (
+                f"// Test: {self.test_function_name}\n"
+                f"// File: {test_path.name}\n"
+                f"// Testing function: {self.function_getting_tested}"
+            )
 
         if self.test_class_name:
             for stmt in module_node.body:

tests/languages/javascript/test_support_dispatch.py

@@ -182,9 +182,9 @@ def test_passes_loop_parameters(self, mock_vitest_runner: MagicMock, js_support:
 
             call_kwargs = mock_vitest_runner.call_args.kwargs
             assert call_kwargs["min_loops"] == 10
-            # JS/TS always uses high max_loops (100_000) regardless of passed value
+            # JS/TS uses JS_BENCHMARKING_MAX_LOOPS (5_000) regardless of passed value
             # Actual loop count is limited by target_duration, not max_loops
-            assert call_kwargs["max_loops"] == 100_000
+            assert call_kwargs["max_loops"] == 5_000
             assert call_kwargs["target_duration_ms"] == 5000