Merge pull request swiftlang#124 from dabelknap/tupledecl

Add support for tuple declarations

Author: allevato

Sources/PrettyPrint/TokenStreamCreator.swift

@@ -92,6 +92,22 @@ private final class TokenStreamCreator: SyntaxVisitor {
   }
 
   override func visit(_ node: TupleExprSyntax) {
+    after(
+      node.leftParen,
+      tokens: .break(size: 0, offset: 2), .open(.consistent, 0), .break(size: 0),
+        .open(.consistent, 0)
+    )
+    before(node.rightParen, tokens: .close, .break(size: 0, offset: -2), .close)
+    super.visit(node)
+  }
+
+  override func visit(_ node: TupleElementSyntax) {
+    before(node.firstToken, tokens: .open)
+    if let trailingComma = node.trailingComma {
+      after(trailingComma, tokens: .close, .break)
+    } else {
+      after(node.lastToken, tokens: .close)
+    }
     super.visit(node)
   }
 
@@ -708,11 +724,6 @@ private final class TokenStreamCreator: SyntaxVisitor {
     super.visit(node)
   }
 
-  override func visit(_ node: TupleElementSyntax) {
-    after(node.trailingComma, tokens: .break)
-    super.visit(node)
-  }
-
   override func visit(_ node: VariableDeclSyntax) {
     if let attributes = node.attributes {
       before(node.firstToken, tokens: .space(size: 0), .open(.consistent, 0))

Tests/PrettyPrinterTests/TupleDeclTests.swift

@@ -0,0 +1,37 @@
+public class TupleDeclTests: PrettyPrintTestCase {
+  public func testBasicTuples() {
+    let input =
+      """
+      let a = (1, 2, 3)
+      let a: (Int, Int, Int) = (1, 2, 3)
+      let a = (1, 2, 3, 4, 5, 6, 7, 8, 9, 10)
+      let a = (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
+      """
+
+    let expected =
+      """
+      let a = (1, 2, 3)
+      let a: (Int, Int, Int) = (1, 2, 3)
+      let a = (
+        1, 2, 3, 4, 5, 6, 7, 8, 9, 10
+      )
+      let a = (
+        1,
+        2,
+        3,
+        4,
+        5,
+        6,
+        7,
+        8,
+        9,
+        10,
+        11,
+        12
+      )
+
+      """
+
+    assertPrettyPrintEqual(input: input, expected: expected, linelength: 37)
+  }
+}