[NFC] Remove Legacy Parser-Based Redeclaration Diagnostics

Author: CodaFi

include/swift/AST/DiagnosticsCommon.def

@@ -38,9 +38,6 @@ ERROR(cannot_parse_group_info_file,none,
 ERROR(error_no_group_info,none,
       "no group info found for file: '%0'", (StringRef))
 
-NOTE(previous_decldef,none,
-     "previous definition of %0 is here", (DeclBaseName))
-
 NOTE(brace_stmt_suggest_do,none,
      "did you mean to use a 'do' statement?", ())
 

include/swift/AST/DiagnosticsParse.def

@@ -219,8 +219,6 @@ ERROR(number_cant_start_decl_name,none,
       (StringRef))
 ERROR(expected_identifier_after_case_comma, PointsToFirstBadToken,
       "expected identifier after comma in enum 'case' declaration", ())
-ERROR(decl_redefinition,none,
-      "definition conflicts with previous value", ())
 ERROR(let_cannot_be_computed_property,none,
       "'let' declarations cannot be computed properties", ())
 ERROR(let_cannot_be_observing_property,none,

include/swift/Parse/Parser.h

@@ -784,9 +784,7 @@ class Parser {
     return diagnose(Tok.getLoc(),
                     Diagnostic(DiagID, std::forward<ArgTypes>(Args)...));
   }
-  
-  void diagnoseRedefinition(ValueDecl *Prev, ValueDecl *New);
-  
+    
   /// Add a fix-it to remove the space in consecutive identifiers.
   /// Add a camel-cased option if it is different than the first option.
   void diagnoseConsecutiveIDs(StringRef First, SourceLoc FirstLoc,

lib/Parse/Parser.cpp

@@ -1159,15 +1159,6 @@ Parser::parseList(tok RightK, SourceLoc LeftLoc, SourceLoc &RightLoc,
   return Status;
 }
 
-/// diagnoseRedefinition - Diagnose a redefinition error, with a note
-/// referring back to the original definition.
-
-void Parser::diagnoseRedefinition(ValueDecl *Prev, ValueDecl *New) {
-  assert(New != Prev && "Cannot conflict with self");
-  diagnose(New->getLoc(), diag::decl_redefinition);
-  diagnose(Prev->getLoc(), diag::previous_decldef, Prev->getBaseName());
-}
-
 Optional<StringRef>
 Parser::getStringLiteralIfNotInterpolated(SourceLoc Loc,
                                           StringRef DiagText) {