Add react exhaustive dependencies linter rule

CHANGELOG.md

@@ -2,6 +2,7 @@
 This project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 ## [Unreleased](https://github.com/Kampfkarren/selene/compare/0.29.0...HEAD)
+- Added new [`roblox_react_exhaustive_deps` lint](https://kampfkarren.github.io/selene/lints/roblox_react_exhaustive_deps.html), which will warn when React hook dependencies are missing or unnecessary.
 
 ## [0.29.0](https://github.com/Kampfkarren/selene/releases/tag/0.29.0) - 2025-07-23
 - Added `Instance.fromExisting` to the Roblox standard library

docs/src/SUMMARY.md

@@ -34,6 +34,7 @@
   - [restricted_module_paths](./lints/restricted_module_paths.md)
   - [roblox_incorrect_color3_new_bounds](./lints/roblox_incorrect_color3_new_bounds.md)
   - [roblox_incorrect_roact_usage](./lints/roblox_incorrect_roact_usage.md)
+  - [roblox_react_exhaustive_deps](./lints/roblox_react_exhaustive_deps.md)
   - [roblox_manual_fromscale_or_fromoffset](./lints/roblox_manual_fromscale_or_fromoffset.md)
   - [roblox_suspicious_udim2_new](./lints/roblox_suspicious_udim2_new.md)
   - [shadowing](./lints/shadowing.md)

docs/src/lints/roblox_react_exhaustive_deps.md

@@ -0,0 +1,88 @@
+# roblox_react_exhaustive_deps
+
+## What it does
+Checks that all dependencies used inside React/Roact hooks like `useEffect`, `useCallback`, and `useMemo` are correctly specified in the dependency array.
+
+## Why this is bad
+Missing dependencies can cause your effects or memoized values to use stale data, leading to bugs. Unnecessary dependencies can cause unnecessary re-renders or re-computations, hurting performance.
+
+When you reference a variable inside a React hook callback, React expects you to declare it as a dependency so it knows when to re-run the effect or recompute the value. Failing to do so can lead to:
+
+1. **Stale closures**: The callback captures the variable's value from when it was created, not its current value
+2. **Missing updates**: Changes to dependencies won't trigger the effect to re-run
+3. **Hard-to-debug issues**: The behavior might work initially but break when component re-renders occur in different orders
+
+## Example
+
+### Missing dependencies
+```lua
+local React = require(Packages.React)
+
+local function Component(props)
+    -- Bad: props.userId is used but not in dependencies
+    React.useEffect(function()
+        fetchUser(props.userId)
+    end, {})
+
+    -- Good: all dependencies are listed
+    React.useEffect(function()
+        fetchUser(props.userId)
+    end, { props.userId })
+end
+```
+
+### Unnecessary dependencies
+```lua
+-- Bad: count is not used in the effect
+React.useEffect(function()
+    print("Hello")
+end, { count })
+
+-- Good: empty dependencies since nothing is used
+React.useEffect(function()
+    print("Hello")
+end, {})
+```
+
+### Property access dependencies
+```lua
+-- Bad: props.user.name is used but not in dependencies
+React.useEffect(function()
+    setTitle(props.user.name)
+end, {})
+
+-- Good: property access is correctly tracked
+React.useEffect(function()
+    setTitle(props.user.name)
+end, { props.user.name })
+```
+
+## Supported hooks
+This lint checks the following React/Roact hooks:
+- `useEffect` - dependencies are the second parameter
+- `useLayoutEffect` - dependencies are the second parameter  
+- `useCallback` - dependencies are the second parameter
+- `useMemo` - dependencies are the second parameter
+- `useImperativeHandle` - dependencies are the third parameter
+
+## Remarks
+This lint works with both the legacy Roact API (using `Roact.useEffect`) and the new React-like API (using `React.useEffect`).
+
+This lint is only active when using the Roblox standard library.
+
+The lint analyzes variable references within the hook callback and compares them against the declared dependency array. It will:
+
+1. Report missing dependencies that are used in the callback but not listed
+2. Report unnecessary dependencies that are listed but not used
+3. Track property access (e.g., `props.value`) as separate dependencies
+4. Ignore built-in Lua globals and Roblox APIs (like `print`, `game`, `workspace`, etc.)
+
+### Limitations
+- The lint assumes variables are stable and doesn't track complex control flow
+- It doesn't detect dependencies in nested function definitions
+- Complex dependency expressions (computed property access with brackets) may not be analyzed correctly
+- setState functions and refs are currently not detected as stable (unlike in React)
+
+## Configuration
+This lint does not have any configuration options.
+

selene-lib/src/lints.rs

@@ -43,6 +43,9 @@ pub mod roblox_incorrect_color3_new_bounds;
 #[cfg(feature = "roblox")]
 pub mod roblox_incorrect_roact_usage;
 
+#[cfg(feature = "roblox")]
+pub mod roblox_react_exhaustive_deps;
+
 #[cfg(feature = "roblox")]
 pub mod roblox_manual_fromscale_or_fromoffset;