Merge pull request #20959 from rintaro/ide-completion-identaftercctok

[CodeCompletion] Eat identifier characters after CC position

Author: rintaro

lib/Parse/Lexer.cpp

@@ -2386,6 +2386,8 @@ void Lexer::lexImpl() {
   case 0:
     switch (getNulCharacterKind(CurPtr - 1)) {
     case NulCharacterKind::CodeCompletion:
+      while (advanceIfValidContinuationOfIdentifier(CurPtr, BufferEnd))
+        ;
       return formToken(tok::code_complete, TokStart);
 
     case NulCharacterKind::BufferEnd:

test/IDE/complete_decl_attribute.swift

@@ -2,6 +2,7 @@
 // RUN: %target-swift-ide-test -code-completion -source-filename %s -code-completion-token=AVAILABILITY2 | %FileCheck %s -check-prefix=AVAILABILITY2
 // RUN: %target-swift-ide-test -code-completion -source-filename %s -code-completion-token=KEYWORD2 | %FileCheck %s -check-prefix=KEYWORD2
 // RUN: %target-swift-ide-test -code-completion -source-filename %s -code-completion-token=KEYWORD3 | %FileCheck %s -check-prefix=KEYWORD3
+// RUN: %target-swift-ide-test -code-completion -source-filename %s -code-completion-token=KEYWORD3_2 | %FileCheck %s -check-prefix=KEYWORD3
 // RUN: %target-swift-ide-test -code-completion -source-filename %s -code-completion-token=KEYWORD4 | %FileCheck %s -check-prefix=KEYWORD4
 // RUN: %target-swift-ide-test -code-completion -source-filename %s -code-completion-token=KEYWORD5 | %FileCheck %s -check-prefix=KEYWORD5
 // RUN: %target-swift-ide-test -code-completion -source-filename %s -code-completion-token=KEYWORD_LAST | %FileCheck %s -check-prefix=KEYWORD_LAST
@@ -63,6 +64,10 @@ class C {}
 // KEYWORD3-NEXT:             Keyword/None:                       usableFromInline[#Class Attribute#]; name=usableFromInline
 // KEYWORD3-NEXT:             End completions
 
+@#^KEYWORD3_2^#IB
+class C2 {}
+// Same as KEYWORD3.
+
 @#^KEYWORD4^#
 enum E {}
 // KEYWORD4:                  Begin completions, 5 items