WeakSelfInEscapingClosures [rule] v0.1.0

Strong captures inside an @escaping closure that the receiver itself stores — completion blocks, Combine subscribers, NotificationCenter observers, async tasks held on a controller, timer handlers — create a retain cycle. The receiver retains the closure, the closure retains the receiver, neither deinits. The fix is [weak self] in the capture list, paired with a guard let self else { return } (or optional-chained self?.) inside the body.

Checks

• Every @escaping closure that is stored on self (or on an object that outlives self) captures self with [weak self].
• After the capture, the body either uses self?.x or unwraps once at the top with guard let self else { return }.
• Timer, NotificationCenter, KVO, and Combine subscriptions stored on a view controller use [weak self] in their handler closures.
• Non-escaping closures (e.g. the closure passed to array.map, forEach, sync withLock) do not need [weak self] — strong is fine because the closure does not outlive the call.
• When [weak self] would force the closure to do nothing useful if self is gone, but the work must still complete, capture [weak self] plus a strong copy of the specific dependency the closure actually needs.

Label

Capture self weakly in any escaping closure stored on self or owned by a longer-lived object

WeakSelfInEscapingClosures [rule] v0.1.0

Strong captures inside an @escaping closure that the receiver itself stores — completion blocks, Combine subscribers, NotificationCenter observers, async tasks held on a controller, timer handlers — create a retain cycle. The receiver retains the closure, the closure retains the receiver, neither deinits. The fix is [weak self] in the capture list, paired with a guard let self else { return } (or optional-chained self?.) inside the body.

Checks

• Every @escaping closure that is stored on self (or on an object that outlives self) captures self with [weak self].
• After the capture, the body either uses self?.x or unwraps once at the top with guard let self else { return }.
• Timer, NotificationCenter, KVO, and Combine subscriptions stored on a view controller use [weak self] in their handler closures.
• Non-escaping closures (e.g. the closure passed to array.map, forEach, sync withLock) do not need [weak self] — strong is fine because the closure does not outlive the call.
• When [weak self] would force the closure to do nothing useful if self is gone, but the work must still complete, capture [weak self] plus a strong copy of the specific dependency the closure actually needs.

Label

Capture self weakly in any escaping closure stored on self or owned by a longer-lived object

Label

Capture self weakly in any escaping closure stored on self or owned by a longer-lived object