Merge pull request swiftlang#244 from dabelknap/overhanging-comma

Fix a bug where a delimiting comma could exceed the line limit.

Author: dabelknap

Sources/SwiftFormatPrettyPrint/TokenStreamCreator.swift

@@ -962,7 +962,13 @@ private final class TokenStreamCreator: SyntaxVisitor {
   }
 
   override func visit(_ node: ConditionElementSyntax) -> SyntaxVisitorContinueKind {
-    after(node.trailingComma, tokens:. break)
+    before(node.firstToken, tokens: .open)
+    if let comma = node.trailingComma {
+      after(comma, tokens: .close, .break)
+    }
+    else {
+      after(node.lastToken, tokens: .close)
+    }
     return .visitChildren
   }
 
@@ -1375,9 +1381,7 @@ private final class TokenStreamCreator: SyntaxVisitor {
   }
 
   override func visit(_ node: OptionalBindingConditionSyntax) -> SyntaxVisitorContinueKind {
-    before(node.firstToken, tokens: .open)
     after(node.letOrVarKeyword, tokens: .break)
-    after(node.lastToken, tokens: .close)
     return .visitChildren
   }
 

Tests/SwiftFormatPrettyPrintTests/IfStmtTests.swift

@@ -182,4 +182,26 @@ public class IfStmtTests: PrettyPrintTestCase {
 
     assertPrettyPrintEqual(input: input, expected: expected, linelength: 30)
   }
+
+  public func testIfLetStatements() {
+    let input =
+      """
+      if let SomeReallyLongVar = Some.More.Stuff(), let a = myfunc() {
+        // do stuff
+      }
+      """
+
+    let expected =
+      """
+      if let SomeReallyLongVar
+        = Some.More.Stuff(), let a = myfunc()
+      {
+        // do stuff
+      }
+
+      """
+
+    // The line length ends on the last paren of .Stuff()
+    assertPrettyPrintEqual(input: input, expected: expected, linelength: 44)
+  }
 }