Allow trailing closures with a line break before '{'.

Swift SVN r19322

Author: jckarter

include/swift/Parse/Token.h

@@ -166,11 +166,6 @@ class Token {
     return !isAtStartOfLine() && Kind == tok::l_square;
   }
 
-  /// True if the token is an l_brace token that does not start a new line.
-  bool isFollowingLBrace() const {
-    return !isAtStartOfLine() && Kind == tok::l_brace;
-  }
-
   /// True if the token is any keyword.
   bool isKeyword() const {
     switch (Kind) {

lib/Parse/ParseExpr.cpp

@@ -491,7 +491,7 @@ ParserResult<Expr> Parser::parseExprNew() {
 
   // Check for an initialization closure.
   Expr *constructExpr = nullptr;
-  if (Tok.isFollowingLBrace()) {
+  if (Tok.is(tok::l_brace)) {
     ParserResult<Expr> construction = parseExprClosure();
     if (construction.hasCodeCompletion())
       return construction;
@@ -912,7 +912,7 @@ ParserResult<Expr> Parser::parseExprPostfix(Diag<> ID, bool isExprBasic) {
       consumeToken(tok::period_prefix);
       IsPeriod = peekToken().isFollowingLParen() ||
                  peekToken().isFollowingLSquare() ||
-                 peekToken().isFollowingLBrace();
+                 peekToken().is(tok::l_brace);
     }
     if (consumeIf(tok::period) || (IsPeriod && consumeIf(tok::period_prefix))) {
       // Non-identifier cases.
@@ -1125,7 +1125,7 @@ ParserResult<Expr> Parser::parseExprPostfix(Diag<> ID, bool isExprBasic) {
     }
 
     // Check for a trailing closure, if allowed.
-    if (!isExprBasic && Tok.isFollowingLBrace() &&
+    if (!isExprBasic && Tok.is(tok::l_brace) &&
         !isStartOfGetSetAccessor(*this)) {
       // Parse the closure.
       ParserResult<Expr> closure = parseExprClosure();
@@ -1154,7 +1154,7 @@ ParserResult<Expr> Parser::parseExprPostfix(Diag<> ID, bool isExprBasic) {
 
       // We only allow a single trailing closure on a call.  This could be
       // generalized in the future, but needs further design.
-      if (Tok.isFollowingLBrace()) break;
+      if (Tok.is(tok::l_brace)) break;
       continue;
     }
 

test/Interpreter/arrays.swift

@@ -56,7 +56,7 @@ println()
 // CHECK: dead
 // CHECK: dead
 // CHECK: dead
-{ [Canary(), Canary(), Canary()] }()
+_ = { [Canary(), Canary(), Canary()] }()
 
 // Create an array of (String, Bool) pairs. <rdar://problem/16916422>
 do {

test/Parse/toplevel_library_invalid.swift

@@ -3,8 +3,8 @@
 println("a"); // expected-error {{expressions are not allowed at the top level}}
 println("a"); // expected-error {{expressions are not allowed at the top level}}
 // Make sure we don't crash on closures at the top level
-{ } // expected-error {{expressions are not allowed at the top level}} expected-error {{braced block of statements}}
-{ 5 }() // expected-error {{expressions are not allowed at the top level}}
+({ }) // expected-error {{expressions are not allowed at the top level}}
+({ 5 }()) // expected-error {{expressions are not allowed at the top level}}
 
 // FIXME: Too many errors for this.
 for i // expected-error 2 {{expected ';' in 'for' statement}} 

test/expr/closure/trailing.swift

@@ -44,8 +44,10 @@ var a = C().map {$0 + 1}.filter {$0 % 3 == 0}
 var b = C().map {$0 + 1}
   .filter {$0 % 3 == 0}
 
-
-
+var c = C().map
+{
+  $0 + 1
+}
 
 
 // Calls with multiple trailing closures should be rejected until we have time