Invalid fix-it on unused optional binding when multiple conditions

Description

func sync() -> Int? {}
func async() async -> Int? {}
do {
  if let x = sync(), true {} // bad fix-it
  if let x = sync() {}      // good fix-it

  if let x = await async(), true {} // bad fix-it
  if let x = await async() {}     // good fix-it
}

warning: immutable value 'x' was never used; consider replacing with '_' or removing it [#NoUsage]
  if let x = sync(), true {}
     ~~~~^
     _
warning: value 'x' was defined but never used; consider replacing with boolean test [#NoUsage]
  if let x = sync() {}
     ~~~~^~~~
                    != nil
warning: immutable value 'x' was never used; consider replacing with '_' or removing it [#NoUsage]
  if let x = await async(), true {}
     ~~~~^
     _
warning: value 'x' was defined but never used; consider replacing with boolean test [#NoUsage]
  if let x = await async() {}
     ~~~~^~~~
     (                    ) != nil

Contributor guide

Tech stack

swift

Domain

toolingdeveloper experience

Issue type

bug

DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.

4

Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.

1-2 days

Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.

blocked

ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.

clear

Prerequisites

Swift compiler internalsDiagnostic fix it handlingSource code modification

Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.

20

Research direction

The issue has an assignee (blocked). The fix requires understanding why the fix it for unused optional binding differs with multiple conditions. Likely involves examining the diagnostic emission for the '#NoUsage' warning in the Swift compiler, possibly in the type checker or diagnostic passes. Check issue comments for any maintainer guidance or previous attempts. The user also requests adding tests for both orderings of conditions.