scannedinc Xojo Lint
scripts/xojo_lint.py validates and formats Xojo project files. It needs only Python 3.9 or later and the standard library. Run it from the folder of this skill, or give the full path to the script.
Commands
After you create or edit files in a Xojo project, run both checks:
python3 scripts/xojo_lint.py check --all PATH
python3 scripts/xojo_lint.py format --check PATH
Both commands are silent and exit 0 when the project is clean. PATH is a project folder or one file; it defaults to the current directory.
If format --check reports files, inspect the changes, then apply them:
python3 scripts/xojo_lint.py format --diff PATH
python3 scripts/xojo_lint.py format PATH
The formatter only changes serialization details it can identify safely: tag case and nesting, whitespace around manifest keys, missing minimum indentation inside source tags, and a missing line break at the end of a file -- except in .xojo_script, which Xojo writes both ways, so use --final-newline add to force one there. It does not reorder properties and does not rewrite Xojo expressions, identifiers, comments, or string literals, including the trailing whitespace of a manifest value. Never format a project the user has designated read-only.
Reading the output
Each diagnostic is one line: path:line:column: severity CODE message. There are three severities:
- error — the file breaks its format. Errors always fail the run.
- warning — the file is unusual but usable. Warnings fail the run only with
--warnings-as-errors. - notice — a nit, for example a missing final line break. Notices never fail the run. Hide them with
--no-notices.
check --all enables all optional checks, currently --warn-unknown for unknown .xojo_* containers and tag kinds plus --check-paths for external image and data assets. It does not enable --warnings-as-errors; add that separately when warnings must fail the run.
Unknown properties, keys, and tag kinds are accepted for forward compatibility: a newer IDE can extend the formats, and this tool must not call that corruption.
Diagnostic codes are grouped by container: XJC common text checks, XJT tagged regions, XJB designer blocks, XJP project manifests, XJR resources, XJU UI state, XJL libraries, and XJF formatting.
Scope
The tool understands the text-format extensions (.xojo_project, .xojo_code, .xojo_window, .xojo_menu, .xojo_toolbar, .xojo_report, .xojo_image, .xojo_color, .xojo_filetypeset, .xojo_database_connection, .xojo_script) and the binary companions (.xojo_library, .xojo_resources, .xojo_uistate). Xojo Binary Project and Xojo XML Project files are opaque to this tool: it skips them, and reports them only with --warn-unknown.
As a pre-commit hook
scripts/pre-commit.sample is a ready-to-use git hook for a Xojo project. It lints the staged .xojo_* files and blocks the commit on errors, warnings, or files the formatter would change. To install it into a project, copy it to .git/hooks/pre-commit and make it executable. Its XOJO_LINT default finds xojo_lint.py where Claude Code installs the plugin; for any other install, Codex included, export XOJO_LINT as the real path of the script or set it at the top of the hook.
Tests
python3 scripts/test_xojo_lint.py