Add pre-commit hook to verify static analysis passes & format is correct

[camsim99]

Adds a pre-commit hook that you can install to verify that dart analyze --fatal-infos and the package format are correct when you make a call to git commit. Intended to ensure agents commit code that meets are quality standards.

Miscellaneous notes:

• script/githooks/bin/install_hooks.dart is the script to install the hook that devs would need to run to use it.
• I modeled the new githooks directory like https://github.com/flutter/flutter/tree/master/engine/src/flutter/tools/githooks to make it easier for folks to add new hooks
• The hook separates formatting of Dart and native files as an optimization to avoid all of the configuration that the plugin tool uses to format native files that are not required if no native files have been changed

Pre-Review Checklist

• I read the Contributor Guide and followed the process outlined there for submitting PRs.
• I read the AI contribution guidelines and understand my responsibilities, or I am not using AI tools.
• I read the Tree Hygiene page, which explains my responsibilities.
• I read and followed the relevant style guides and ran the auto-formatter.
• I signed the CLA.
• The title of the PR starts with the name of the package surrounded by square brackets, e.g. [shared_preferences]
• I linked to at least one issue that this PR fixes in the description above.
• I followed the version and CHANGELOG instructions, using semantic versioning and the repository CHANGELOG style, or I have commented below to indicate which documented exception this PR falls under¹.
• I updated/added any relevant documentation (doc comments with ///).
• I added new tests to check the change I am making, or I have commented below to indicate which test exemption this PR falls under¹.
• All existing and new tests are passing.

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Footnotes

1. Regular contributors who have demonstrated familiarity with the repository guidelines only need to comment if the PR is not auto-exempted by repo tooling. ↩ ↩²

[gemini-code-assist]

Code Review

This pull request introduces a new githooks Dart package to automate pre-commit checks, including formatting and static analysis, for staged files. The package includes an installation script, a pre-commit command runner, and associated unit tests. Review feedback highlights a potential infinite loop on Windows when locating the .git directory, raw ANSI escape sequences being printed without verifying terminal support, the use of loose any version constraints in pubspec.yaml, and redundant dead code in the test mocks.

[gemini-code-assist]

On Windows, the root directory path is not '/' (e.g., it could be 'C:\'). Since repoRoot.parent of a drive root returns the drive root itself, checking repoRoot.path != '/' will result in an infinite loop if .git is not found. Comparing repoRoot.path to repoRoot.parent.path is a cross-platform way to detect when the file system root has been reached.

Suggested change

	Directory repoRoot = Directory.current;
	while (repoRoot.path != '/' && !Directory(p.join(repoRoot.path, '.git')).existsSync()) {
	repoRoot = repoRoot.parent;
	}
	if (repoRoot.path == '/') {
	print('❌ Could not find .git directory.');
	exit(1);
	}
	Directory repoRoot = Directory.current;
	while (repoRoot.path != repoRoot.parent.path &&
	!Directory(p.join(repoRoot.path, '.git')).existsSync()) {
	repoRoot = repoRoot.parent;
	}
	if (!Directory(p.join(repoRoot.path, '.git')).existsSync()) {
	print('❌ Could not find .git directory.');
	exit(1);
	}

[gemini-code-assist]

On Windows, the root directory path is not '/' (e.g., it could be 'C:\'). Since repoRoot.parent of a drive root returns the drive root itself, checking repoRoot.path != '/' will result in an infinite loop if .git is not found. Comparing repoRoot.path to repoRoot.parent.path is a cross-platform way to detect when the file system root has been reached.

Suggested change

	Directory repoRoot = Directory.current;
	while (repoRoot.path != '/' && !Directory(p.join(repoRoot.path, '.git')).existsSync()) {
	repoRoot = repoRoot.parent;
	}
	if (repoRoot.path == '/') {
	print('❌ Could not find .git directory.');
	return false;
	}
	Directory repoRoot = Directory.current;
	while (repoRoot.path != repoRoot.parent.path &&
	!Directory(p.join(repoRoot.path, '.git')).existsSync()) {
	repoRoot = repoRoot.parent;
	}
	if (!Directory(p.join(repoRoot.path, '.git')).existsSync()) {
	print('❌ Could not find .git directory.');
	return false;
	}

[gemini-code-assist]

Writing ANSI escape sequences like \x1B[2K\r directly to stdout can produce raw, unreadable characters in environments that do not support them (such as some GUI Git clients or non-interactive CI logs). Checking stdout.supportsAnsiEscapes ensures a clean fallback (like printing a newline) when ANSI escapes are not supported.

Suggested change

	if (!hasError) {
	stdout.write('\x1B[2K\r');
	}
	if (!hasError) {
	stdout.write(stdout.supportsAnsiEscapes ? '\\x1B[2K\\r' : '\\n');
	}

[gemini-code-assist]

Ensure ANSI escape sequences are only printed when supported by the terminal to avoid raw escape characters in non-ANSI environments.

Suggested change

	if (!hasError) {
	stdout.write('\x1B[2K\r✅ Formatting looks good.\n');
	}
	if (!hasError) {
	stdout.write(stdout.supportsAnsiEscapes
	? '\\x1B[2K\\r✅ Formatting looks good.\\n'
	: '✅ Formatting looks good.\\n');
	}

[gemini-code-assist]

Using any version constraints for dependencies is discouraged as it can lead to unexpected breaking changes or build failures when new major versions of these packages are released. It is recommended to use caret constraints to specify compatible version ranges.

dependencies:
  args: ^2.4.2
  path: ^1.9.0

dev_dependencies:
  test: ^1.24.0

[gemini-code-assist]

The check for --show-toplevel is dead code because PreCommitCommand does not invoke git rev-parse --show-toplevel. Removing this block simplifies the test mock.

              if (executable == 'git') {
                return ProcessResult(0, 0, 'script/githooks/lib/githooks.dart\\n', '');
              }

[gemini-code-assist]

The check for --show-toplevel is dead code because PreCommitCommand does not invoke git rev-parse --show-toplevel. Removing this block simplifies the test mock.

              if (executable == 'git') {
                return ProcessResult(0, 0, 'script/githooks/lib/githooks.dart\\n', '');
              }

[gemini-code-assist]

The check for --show-toplevel is dead code because PreCommitCommand does not invoke git rev-parse --show-toplevel. Removing this block simplifies the test mock.

              if (executable == 'git') {
                return ProcessResult(0, 0, 'script/githooks/lib/githooks.dart\\n', '');
              }

[gemini-code-assist]

The check for --show-toplevel is dead code because PreCommitCommand does not invoke git rev-parse --show-toplevel. Removing this block simplifies the test mock.

              if (executable == 'git') {
                return ProcessResult(0, 0, 'README.md\\n', '');
              }