Fix bug in unusedArguments when shadowing function argument with cond…

…itional assignment declaration (#1687)
nicklockwood · May 12, 2024 · 816356e · 816356e
1 parent 88f6080
commit 816356e
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Showing 2 changed files with 67 additions and 1 deletion.
diff --git a/Sources/Rules.swift b/Sources/Rules.swift
@@ -3413,7 +3413,11 @@ public struct _FormatRules {
             }
             var i = range.lowerBound
             while i < range.upperBound {
-                if formatter.isStartOfStatement(at: i, treatingCollectionKeysAsStart: false) {
+                if formatter.isStartOfStatement(at: i, treatingCollectionKeysAsStart: false),
+                   // Immediately following an `=` operator, if or switch keywords
+                   // are expressions rather than statements.
+                   formatter.lastToken(before: i, where: { !$0.isSpaceOrCommentOrLinebreak })?.isOperator("=") != true
+                {
                     pushLocals()
                     wasDeclaration = false
                 }

diff --git a/Tests/RulesTests+Redundancy.swift b/Tests/RulesTests+Redundancy.swift
@@ -8096,6 +8096,68 @@ class RedundancyTests: RulesTests {
         testFormatting(for: input, output, rule: FormatRules.unusedArguments)
     }
 
+    func testUnusedArgumentWithClosureShadowingParamName() {
+        let input = """
+        func test(foo: Foo) {
+            let foo = {
+                if foo.bar {
+                    baaz
+                } else {
+                    bar
+                }
+            }()
+            print(foo)
+        }
+        """
+        testFormatting(for: input, rule: FormatRules.unusedArguments)
+    }
+
+    func testUnusedArgumentWithConditionalAssignmentShadowingParamName() {
+        let input = """
+        func test(foo: Foo) {
+            let foo =
+                if foo.bar {
+                    baaz
+                } else {
+                    bar
+                }
+            print(foo)
+        }
+        """
+        testFormatting(for: input, rule: FormatRules.unusedArguments)
+    }
+
+    func testUnusedArgumentWithSwitchAssignmentShadowingParamName() {
+        let input = """
+        func test(foo: Foo) {
+            let foo =
+                switch foo.bar {
+                case true:
+                    baaz
+                case false:
+                    bar
+                }
+            print(foo)
+        }
+        """
+        testFormatting(for: input, rule: FormatRules.unusedArguments)
+    }
+
+    func testUnusedArgumentWithConditionalAssignmentNotShadowingParamName() {
+        let input = """
+        func test(bar: Bar) {
+            let quux =
+                if foo {
+                    bar
+                } else {
+                    baaz
+                }
+            print(quux)
+        }
+        """
+        testFormatting(for: input, rule: FormatRules.unusedArguments)
+    }
+
     // MARK: redundantClosure
 
     func testRemoveRedundantClosureInSingleLinePropertyDeclaration() {