feat(timers deprecation): introduce

[AugustinMauroy]

TODO

• put shared into utilities package
• add more doc

[AugustinMauroy]

I need review on test cases so I can finish/clean the implementation

[Copilot]

Pull Request Overview

This PR introduces a comprehensive codemod recipe to migrate deprecated Node.js timers APIs to modern timer functions. The codemod replaces timers.enroll(), timers.unenroll(), timers.active(), and timers._unrefActive() with standard setTimeout(), clearTimeout(), and Timer#unref() constructs, addressing Node.js deprecations DEP0095, DEP0096, DEP0126, and DEP0127.

Key changes include:

• New utility functions for GCD calculation and indent detection in the codemod-utils package
• Five transformation modules that handle different deprecated APIs
• Comprehensive test suite covering various import/require patterns
• Automated cleanup of unused imports after transformations

Reviewed Changes

Copilot reviewed 45 out of 46 changed files in this pull request and generated 107 comments.

Show a summary per file

File	Description
utils/src/math.ts	Implements GCD function to calculate indentation units
utils/src/math.test.ts	Tests for GCD function including edge cases
utils/src/ast-grep/indent.ts	Detects indentation style and retrieves line indentation
utils/src/ast-grep/indent.test.ts	Tests for indentation detection utilities
utils/src/ast-grep/general.ts	Helper functions for AST manipulation
utils/src/ast-grep/general.test.ts	Tests for AST manipulation helpers
recipes/timers-deprecations/src/*.ts	Five transformation modules for each deprecated API
recipes/timers-deprecations/tests/**	Comprehensive test cases for all transformations
recipes/timers-deprecations/workflow.yaml	Workflow configuration for codemod execution
recipes/timers-deprecations/package.json	Package configuration and test scripts
recipes/timers-deprecations/codemod.yaml	Codemod metadata and registry configuration
recipes/timers-deprecations/README.md	Documentation with examples and caveats

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[JakobJingleheimer]

Thanks for this and sorry it's taken me a quite a while to get to it. It's been a helluva month :(

[JakobJingleheimer]

Where does the content for timeout handler come from?

Suggested change

	**Before:**
	```js
	const timers = require('node:timers');
	const resource = { _idleTimeout: 1500 };
	timers.enroll(resource, 1500);
	```
	**After:**
	```js
	const resource = { timeout: setTimeout(() => {
	// timeout handler
	}, 1500) };
	```
	```diff
	- const timers = require('node:timers');
	- const resource = { _idleTimeout: 1500 };
	+ const resource = { timeout: setTimeout(() => {
	+ // timeout handler
	+ }, 1500) };
	- timers.enroll(resource, 1500);

[AugustinMauroy]

Where does the content for timeout handler come from?

my brain 😅

[JakobJingleheimer]

Suggested change

	**Before:**
	```js
	timers.unenroll(resource);
	```
	**After:**
	```js
	clearTimeout(resource.timeout);
	```
	```diff
	- timers.unenroll(resource);
	+ clearTimeout(resource.timeout);

[JakobJingleheimer]

Where do onTimeout and delay come from? they aren't in the original or new code

Suggested change

	**Before:**
	```js
	const timers = require('node:timers');
	timers.active(resource);
	timers._unrefActive(resource);
	```
	**After:**
	```js
	const handle = setTimeout(onTimeout, delay);
	handle.unref();
	```
	```diff
	- const timers = require('node:timers');
	- timers.active(resource);
	- timers._unrefActive(resource);
	+ const handle = setTimeout(onTimeout, delay);
	+ handle.unref();

[JakobJingleheimer]

@AugustinMauroy I tried to review the rest of this, but the browser tab crashes trying to load it (it's big, but I didn't think it was that big). Would it be possible to break this into smaller pieces?