Unity-Technologies/UnityCsReference · error · ArgumentNullException

path

Error message

path

What it means

The single-path overload of AssetDatabase.MakeEditable delegates to the array overload via MakeEditable(new[] {path}). It throws ArgumentNullException when path is null, because the null guard runs before the array wrapping and before any version-control checkout logic. MakeEditable marks an asset as editable (checks it out) in the active version-control provider.

Source

Thrown at Editor/Mono/AssetDatabase/AssetDatabase.cs:136

            if (assetOrMetaFilePaths == null)
                throw new ArgumentNullException(nameof(assetOrMetaFilePaths));
            if (outNotEditablePaths == null)
                throw new ArgumentNullException(nameof(outNotEditablePaths));
            UnityEngine.Profiling.Profiler.BeginSample("AssetDatabase.IsOpenForEdit");
            AssetModificationProcessorInternal.IsOpenForEdit(assetOrMetaFilePaths, outNotEditablePaths, statusQueryOptions);
            UnityEngine.Profiling.Profiler.EndSample();
        }

        [RequiredByNativeCode]
        private static bool Internal_MakeEditable(string path)
        {
            return MakeEditable(path);
        }

        public static bool MakeEditable(string path)
        {
            if (path == null)
                throw new ArgumentNullException(nameof(path));
            return MakeEditable(new[] {path});
        }

        [RequiredByNativeCode]
        private static bool Internal_MakeEditable2(string[] paths, string prompt = null, List<string> outNotEditablePaths = null)
        {
            return MakeEditable(paths, prompt, outNotEditablePaths);
        }

        public static bool MakeEditable(string[] paths, string prompt = null, List<string> outNotEditablePaths = null)
        {
            if (paths == null)
                throw new ArgumentNullException(nameof(paths));
            UnityEngine.Profiling.Profiler.BeginSample("AssetDatabase.MakeEditable");
            ChangeSet changeSet = null;
            var result = Provider.HandlePreCheckoutCallback(ref paths, ref changeSet);
            if (result && !AssetModificationProcessorInternal.MakeEditable(paths, prompt, outNotEditablePaths))
                result = false;

View on GitHub (pinned to 225b0fbdb5)

Solutions

1. Guard the path: if (!string.IsNullOrEmpty(path)) AssetDatabase.MakeEditable(path).
2. Ensure the path source (GUIDToAssetPath, Selection.activeObject, etc.) is validated and non-null before use.
3. Use a helper that returns empty string instead of null from path-resolution logic.

Example fix

// before
AssetDatabase.MakeEditable(resolvedPath);

// after
if (!string.IsNullOrEmpty(resolvedPath))
    AssetDatabase.MakeEditable(resolvedPath);

if (!string.IsNullOrEmpty(path))
    AssetDatabase.MakeEditable(path);

static bool IsValidAssetPath(string path) => !string.IsNullOrEmpty(path);

try { AssetDatabase.MakeEditable(path); }
catch (ArgumentNullException ex) when (ex.ParamName == "path")
{ Debug.LogWarning($"Cannot make editable: path is null"); }

When it happens

Trigger: Calling AssetDatabase.MakeEditable(null) directly, or passing an asset path variable that was set from a query returning null (e.g., AssetDatabase.GUIDToAssetPath on an invalid GUID returns empty string, but other path APIs can return null).

Common situations: Custom checkout scripts, import post-processors, or tools that auto-checkout assets before modification where the path source can be null due to a missing asset, deleted file, or unresolvable GUID.

Related errors

• paths
• materialFolderPath
• assetOrMetaFilePaths
• outNotEditablePaths
• Cannot add dependency on invalid path.

AI-assisted analysis of Unity-Technologies/UnityCsReference@225b0fbdb5 (2026-08-13). Data as JSON: /api/errors/1d9b1ab86aa064f7. Report an issue: GitHub.