fix: prefer closer config file over parent Java build file in monorepos (TODO-37)

Java detection in parse_config_file() short-circuited before the existing
depth-comparison logic, so a parent pom.xml would override a closer
package.json or pyproject.toml. Now all config sources are detected first
and the closest one to CWD wins.

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

Author: mohamedashrraf222

codeflash/code_utils/config_parser.py

@@ -106,16 +106,21 @@ def find_conftest_files(test_paths: list[Path]) -> list[Path]:
 def parse_config_file(
     config_file_path: Path | None = None, override_formatter_check: bool = False
 ) -> tuple[dict[str, Any], Path]:
-    # Java projects: read config from pom.xml/gradle.properties (no standalone config file needed)
-    if config_file_path is None:
-        java_config = _try_parse_java_build_config()
-        if java_config is not None:
-            config, project_root = java_config
-            return config, project_root
-
+    # Detect all config sources — Java, package.json, pyproject.toml
+    java_result = _try_parse_java_build_config() if config_file_path is None else None
     package_json_path = find_package_json(config_file_path)
     pyproject_toml_path = find_closest_config_file("pyproject.toml") if config_file_path is None else None
 
+    # Use Java config only if no closer JS/Python config exists (monorepo support).
+    # In a monorepo with a parent pom.xml and a child package.json, the closer config wins.
+    if java_result is not None:
+        java_depth = len(java_result[1].parts)
+        has_closer = (package_json_path is not None and len(package_json_path.parent.parts) >= java_depth) or (
+            pyproject_toml_path is not None and len(pyproject_toml_path.parent.parts) >= java_depth
+        )
+        if not has_closer:
+            return java_result
+
     # When both config files exist, prefer the one closer to CWD.
     # This prevents a parent-directory package.json (e.g., monorepo root)
     # from overriding a closer pyproject.toml.

tests/code_utils/test_config_parser.py

@@ -0,0 +1,87 @@
+"""Tests for config_parser.py — monorepo language detection priority."""
+
+from __future__ import annotations
+
+import json
+import os
+from pathlib import Path
+from unittest.mock import patch
+
+import pytest
+
+from codeflash.code_utils.config_parser import parse_config_file
+
+
+class TestMonorepoConfigPriority:
+    """Verify that closer config files win over parent Java build files in monorepos."""
+
+    def test_closer_package_json_wins_over_parent_pom_xml(self, tmp_path: Path) -> None:
+        """In monorepo/frontend/, a local package.json should win over a parent pom.xml."""
+        # Parent Java project
+        (tmp_path / "pom.xml").write_text("<project></project>", encoding="utf-8")
+        (tmp_path / "src" / "main" / "java").mkdir(parents=True)
+
+        # Child JS project
+        frontend = tmp_path / "frontend"
+        frontend.mkdir()
+        (frontend / "package.json").write_text(
+            json.dumps({"name": "frontend", "codeflash": {"moduleRoot": "src"}}),
+            encoding="utf-8",
+        )
+        (frontend / "src").mkdir()
+
+        with patch("codeflash.code_utils.config_parser.Path") as mock_path_cls:
+            mock_path_cls.cwd.return_value = frontend
+            # find_package_json also uses Path.cwd; mock it at the source
+            with patch("codeflash.code_utils.config_js.Path") as mock_js_path_cls:
+                mock_js_path_cls.cwd.return_value = frontend
+                # Also need to let normal Path operations work
+                mock_path_cls.side_effect = Path
+                mock_path_cls.cwd.return_value = frontend
+                mock_js_path_cls.side_effect = Path
+                mock_js_path_cls.cwd.return_value = frontend
+
+                config, root = parse_config_file()
+
+        # Should detect JS, not Java
+        assert config.get("language") != "java", (
+            "Closer package.json should take priority over parent pom.xml"
+        )
+
+    def test_java_wins_when_no_closer_js_config(self, tmp_path: Path) -> None:
+        """When only a pom.xml exists (no package.json/pyproject.toml closer), Java config wins."""
+        (tmp_path / "pom.xml").write_text("<project></project>", encoding="utf-8")
+        (tmp_path / "src" / "main" / "java").mkdir(parents=True)
+
+        with patch("codeflash.code_utils.config_parser.Path") as mock_path_cls:
+            mock_path_cls.side_effect = Path
+            mock_path_cls.cwd.return_value = tmp_path
+            with patch("codeflash.code_utils.config_js.Path") as mock_js_path_cls:
+                mock_js_path_cls.side_effect = Path
+                mock_js_path_cls.cwd.return_value = tmp_path
+
+                config, root = parse_config_file()
+
+        assert config.get("language") == "java"
+
+    def test_same_level_package_json_wins_over_pom_xml(self, tmp_path: Path) -> None:
+        """When pom.xml and package.json are at the same level, package.json wins (more specific)."""
+        (tmp_path / "pom.xml").write_text("<project></project>", encoding="utf-8")
+        (tmp_path / "src" / "main" / "java").mkdir(parents=True)
+        (tmp_path / "package.json").write_text(
+            json.dumps({"name": "mixed-project", "codeflash": {"moduleRoot": "src"}}),
+            encoding="utf-8",
+        )
+
+        with patch("codeflash.code_utils.config_parser.Path") as mock_path_cls:
+            mock_path_cls.side_effect = Path
+            mock_path_cls.cwd.return_value = tmp_path
+            with patch("codeflash.code_utils.config_js.Path") as mock_js_path_cls:
+                mock_js_path_cls.side_effect = Path
+                mock_js_path_cls.cwd.return_value = tmp_path
+
+                config, root = parse_config_file()
+
+        assert config.get("language") != "java", (
+            "Same-level package.json should take priority over pom.xml"
+        )