Fix nicklockwood#1991: Disable trailingComma for capture lists

Author: askvortsov-yandex-team

Sources/Rules/TrailingCommas.swift

@@ -21,11 +21,16 @@ public extension FormatRule {
                 formatter.addOrRemoveTrailingComma(beforeEndOfScope: i, trailingCommaSupported: true, isCollection: true)
                 return
 
-            case .subscript, .captureList, .functionCall, .parameterList:
+            case .subscript, .functionCall, .parameterList:
                 let trailingCommaSupported = formatter.options.swiftVersion >= "6.1"
                 formatter.addOrRemoveTrailingComma(beforeEndOfScope: i, trailingCommaSupported: trailingCommaSupported)
                 return
 
+            case .captureList:
+                // Trailing commas in closure capture lists are not supported by the compiler yet.
+                formatter.addOrRemoveTrailingComma(beforeEndOfScope: i, trailingCommaSupported: false)
+                return
+
             case .arrayType, .dictionaryType, .throwsType:
                 return
 

Tests/Rules/TrailingCommasTests.swift

@@ -1438,23 +1438,16 @@ final class TrailingCommasTests: XCTestCase {
         testFormatting(for: input, output, rule: .trailingCommas, options: options)
     }
 
-    func testTrailingCommasAddedToCaptureList() {
+    func testTrailingCommasNotAddedToCaptureListSwift6_1() {
         let input = """
         { [
             capturedValue1,
             capturedValue2
         ] in
         }
         """
-        let output = """
-        { [
-            capturedValue1,
-            capturedValue2,
-        ] in
-        }
-        """
         let options = FormatOptions(trailingCommas: .always, swiftVersion: "6.1")
-        testFormatting(for: input, output, rule: .trailingCommas, options: options)
+        testFormatting(for: input, rule: .trailingCommas, options: options)
     }
 
     func testTrailingCommasRemovedFromSingleElementCaptureList() {
@@ -3038,23 +3031,16 @@ final class TrailingCommasTests: XCTestCase {
         testFormatting(for: input, output, rule: .trailingCommas, options: options)
     }
 
-    func testTrailingCommasAddedToCaptureListSwift6_2() {
+    func testTrailingCommasNotAddedToCaptureListSwift6_2() {
         let input = """
         { [
             capturedValue1,
             capturedValue2
         ] in
         }
         """
-        let output = """
-        { [
-            capturedValue1,
-            capturedValue2,
-        ] in
-        }
-        """
         let options = FormatOptions(trailingCommas: .always, swiftVersion: "6.2")
-        testFormatting(for: input, output, rule: .trailingCommas, options: options)
+        testFormatting(for: input, rule: .trailingCommas, options: options)
     }
 
     func testTrailingCommasRemovedFromSingleElementCaptureListSwift6_2() {