---

yaml
---
r: 322287
b: refs/heads/tensorflow-next
c: 1474ea2
h: refs/heads/master
i:
  322285: 434e77b
  322283: 3007f3f
  322279: 45ac5a8
  322271: 3210d5b

Author: swift-ci

[refs]

@@ -1461,4 +1461,4 @@ refs/heads/master-rebranch: 86e95c23aa0d37f24ec138b7853146c1cead2e40
 refs/heads/rdar-53901732: 9bd06af3284e18a109cdbf9aa59d833b24eeca7b
 refs/heads/revert-26776-subst-always-returns-a-type: 1b8e18fdd391903a348970a4c848995d4cdd789c
 refs/heads/tensorflow-merge: 8b854f62f80d4476cb383d43c4aac2001dde3cec
-refs/heads/tensorflow-next: 5a1cbd415d5112db45db051bd1f43d5f6d576fa6
+refs/heads/tensorflow-next: 1474ea2d6ded88e28dc2fde82bd9243e26b10d3a

branches/tensorflow-next/include/swift/Parse/Parser.h

@@ -425,9 +425,38 @@ class Parser {
     llvm::Optional<SyntaxParsingContext> SynContext;
     bool Backtrack = true;
 
+    /// A token receiver used by the parser in the back tracking scope. This
+    /// receiver will save any consumed tokens during this back tracking scope.
+    /// After the scope ends, it either transfers the saved tokens to the old receiver
+    /// or discard them.
+    struct DelayedTokenReceiver: ConsumeTokenReceiver {
+      /// Keep track of the old token receiver in the parser so that we can recover
+      /// after the backtracking sope ends.
+      llvm::SaveAndRestore<ConsumeTokenReceiver*> savedConsumer;
+
+      // Whether the tokens should be transferred to the original receiver.
+      // When the back tracking scope will actually back track, this should be false;
+      // otherwise true.
+      bool shouldTransfer = false;
+      std::vector<Token> delayedTokens;
+      DelayedTokenReceiver(ConsumeTokenReceiver *&receiver):
+        savedConsumer(receiver, this) {}
+      void receive(Token tok) override {
+        delayedTokens.push_back(tok);
+      }
+      ~DelayedTokenReceiver() {
+        if (!shouldTransfer)
+          return;
+        for (auto tok: delayedTokens) {
+          savedConsumer.get()->receive(tok);
+        }
+      }
+    } TempReceiver;
+
   public:
     BacktrackingScope(Parser &P)
-        : P(P), PP(P.getParserPosition()), DT(P.Diags) {
+        : P(P), PP(P.getParserPosition()), DT(P.Diags),
+          TempReceiver(P.TokReceiver) {
       SynContext.emplace(P.SyntaxContext);
       SynContext->setBackTracking();
     }
@@ -440,8 +469,8 @@ class Parser {
       SynContext->setTransparent();
       SynContext.reset();
       DT.commit();
+      TempReceiver.shouldTransfer = true;
     }
-
   };
 
   /// RAII object that, when it is destructed, restores the parser and lexer to

branches/tensorflow-next/test/IDE/coloring_string_interpolation.swift

@@ -0,0 +1,11 @@
+// RUN: %target-swift-ide-test -syntax-coloring -source-filename %s | %FileCheck %s
+// RUN: %target-swift-ide-test -syntax-coloring -typecheck -source-filename %s | %FileCheck %s
+
+// CHECK: <kw>_</kw> = <str>"</str>\<anchor>(</anchor><anchor>)</anchor><str>"</str>
+// CHECK: <kw>if</kw> <kw>true</kw> { <kw>_</kw> = <str>"</str>\<anchor>(</anchor><anchor>)</anchor><str>"</str> }
+
+if true {
+    _ = "\()"
+}
+
+if true { _ = "\()" }