[Parse] Remove special handling for .<keyword><code-complete> (#18869)

At the time this logic was introduced in 8f83ca6, `<expr>.<keyword>` wasn't
allowed. Now that SE-0071 has been implemented, this logic doesn't provide any
positive effects.

Author: rintaro

lib/Parse/ParseExpr.cpp

@@ -1154,17 +1154,6 @@ Parser::parseExprPostfixSuffix(ParserResult<Expr> Result, bool isExprBasic,
         // fallthrough to an UnresolvedDotExpr.
       }
 
-      // If we have '.<keyword><code_complete>', try to recover by creating
-      // an identifier with the same spelling as the keyword.
-      if (Tok.isKeyword() && peekToken().is(tok::code_complete)) {
-        Identifier Name = Context.getIdentifier(Tok.getText());
-        Result = makeParserResult(new (Context) UnresolvedDotExpr(
-            Result.get(), TokLoc, Name, DeclNameLoc(Tok.getLoc()),
-            /*Implicit=*/false));
-        consumeToken();
-        // Fall into the next code completion handler.
-      }
-
       // Handle "x.<tab>" for code completion.
       if (Tok.is(tok::code_complete)) {
         if (CodeCompletion && Result.isNonNull()) {

test/IDE/complete_value_expr.swift

@@ -182,6 +182,10 @@
 // RUN: %target-swift-ide-test -code-completion -source-filename %s -code-completion-token=DOT_EXPR_NON_NOMINAL_1 | %FileCheck %s -check-prefix=DOT_EXPR_NON_NOMINAL_1
 // RUN: %target-swift-ide-test -code-completion -source-filename %s -code-completion-token=DOT_EXPR_NON_NOMINAL_2 | %FileCheck %s -check-prefix=DOT_EXPR_NON_NOMINAL_2
 
+// RUN: %target-swift-ide-test -code-completion -source-filename %s -code-completion-token=KEYWORD_1 | %FileCheck %s -check-prefix=KEYWORD_1
+// RUN: %target-swift-ide-test -code-completion -source-filename %s -code-completion-token=KEYWORD_2 | %FileCheck %s -check-prefix=KEYWORD_2
+// RUN: %target-swift-ide-test -code-completion -source-filename %s -code-completion-token=KEYWORD_3 | %FileCheck %s -check-prefix=KEYWORD_3
+
 // Test code completion of expressions that produce a value.
 
 struct FooStruct {
@@ -1993,3 +1997,31 @@ class TestDotExprWithNonNominal {
 // DOT_EXPR_NON_NOMINAL_2-NOT: firstName
   }
 }
+
+class Cat {
+  struct Inner {
+    var prop1: String
+    var prop2: String
+  }
+  var `class`: Inner
+}
+func testKeyword(cat: Cat) {
+  let _ = cat.#^KEYWORD_1^#
+// KEYWORD_1: Begin completions
+// KEYWORD_1-DAG: Keyword[self]/CurrNominal:          self[#Cat#]; name=self
+// KEYWORD_1-DAG: Decl[InstanceVar]/CurrNominal:      class[#Cat.Inner#]; name=class
+// KEYWORD_1: End completions
+
+  let _ = cat.class#^KEYWORD_2^#
+// KEYWORD_2: Begin completions
+// KEYWORD_2-DAG: Decl[InstanceVar]/CurrNominal:      .prop1[#String#]; name=prop1
+// KEYWORD_2-DAG: Decl[InstanceVar]/CurrNominal:      .prop2[#String#]; name=prop2
+// KEYWORD_2-DAG: BuiltinOperator/None:                = {#Cat.Inner#}[#Void#]; name== Cat.Inner
+// KEYWORD_2: End completions
+
+  let _ = cat.class.#^KEYWORD_3^#
+// KEYWORD_3: Begin completions
+// KEYWORD_3-DAG: Decl[InstanceVar]/CurrNominal:      prop1[#String#]; name=prop1
+// KEYWORD_3-DAG: Decl[InstanceVar]/CurrNominal:      prop2[#String#]; name=prop2
+// KEYWORD_3: End completions
+}