feat: proper windows support

tests/js_compat_test/verify_workspace_shape.sh

@@ -4,10 +4,25 @@ set -euo pipefail
 package_json_launcher="$1"
 package_dir_hint_launcher="$2"
 
-grep -Fq -- 'package_json="${runfiles_dir}/_main/tests/js_compat_test/app/package.json"' "${package_json_launcher}"
-grep -Fq -- 'package_rel_dir_hint="."' "${package_json_launcher}"
-grep -Fq -- 'working_dir_mode="package"' "${package_json_launcher}"
+python3 - "${package_json_launcher}" "${package_dir_hint_launcher}" <<'PY'
+import json
+import pathlib
+import sys
 
-grep -Fq -- 'package_json=""' "${package_dir_hint_launcher}"
-grep -Fq -- 'package_rel_dir_hint="app"' "${package_dir_hint_launcher}"
-grep -Fq -- 'working_dir_mode="package"' "${package_dir_hint_launcher}"
+def read_spec(launcher: str):
+    path = pathlib.Path(launcher)
+    if path.suffix.lower() == ".cmd":
+        path = pathlib.Path(str(path)[:-4])
+    return json.loads(pathlib.Path(f"{path}.launcher.json").read_text())
+
+package_json_spec = read_spec(sys.argv[1])
+package_dir_hint_spec = read_spec(sys.argv[2])
+
+assert package_json_spec["package_json_short_path"].endswith("tests/js_compat_test/app/package.json"), package_json_spec
+assert package_json_spec["package_dir_hint"] == ".", package_json_spec
+assert package_json_spec["working_dir_mode"] == "package", package_json_spec
+
+assert package_dir_hint_spec["package_json_short_path"] == "", package_dir_hint_spec
+assert package_dir_hint_spec["package_dir_hint"] == "app", package_dir_hint_spec
+assert package_dir_hint_spec["working_dir_mode"] == "package", package_dir_hint_spec
+PY