Fix 'unknown documentation command' warning ranges

[erikjv]

Summary

Warnings generated by -Wdocumentation-unknown-command did only have a
start location, not a full source range. This resulted in only the
"carret" being show in messages, and IDEs highlighting only the single
initial character.

Now that the full range is available, nice underlineing can be done, and
tools that support more/other commands than doxygen can filter out those
warnings.

[bkramer]

Nice. Thanks!

[erikjv]

r285056

lib/AST/CommentLexer.cpp

switch(*TokenPtr) {
 
         StringRef CommandName(BufferPtr + 1, Length);
 
         const CommandInfo *Info = Traits.getCommandInfoOrNULL(CommandName);
         if (!Info) {
           if ((Info = Traits.getTypoCorrectCommandInfo(CommandName))) {
             StringRef CorrectedName = Info->Name;
             SourceLocation Loc = getSourceLocation(BufferPtr);
-            SourceRange CommandRange(Loc.getLocWithOffset(1),
-                                     getSourceLocation(TokenPtr));
+            SourceLocation EndLoc = getSourceLocation(TokenPtr);
+            SourceRange FullRange = SourceRange(Loc, EndLoc);
+            SourceRange CommandRange(Loc.getLocWithOffset(1), EndLoc);
             Diag(Loc, diag::warn_correct_comment_command_name)
-              << CommandName << CorrectedName
+              << FullRange << CommandName << CorrectedName
               << FixItHint::CreateReplacement(CommandRange, CorrectedName);
           } else {
             formTokenWithChars(T, TokenPtr, tok::unknown_command);
             T.setUnknownCommandName(CommandName);
-            Diag(T.getLocation(), diag::warn_unknown_comment_command_name);
+            Diag(T.getLocation(), diag::warn_unknown_comment_command_name)
+                << SourceRange(T.getLocation(), T.getEndLocation());
             return;
           }
         }
         if (Info->IsVerbatimBlockCommand) {
           setupAndLexVerbatimBlock(T, TokenPtr, *BufferPtr, Info);
           return;
         }
         if (Info->IsVerbatimLineCommand) {

test/Sema/warn-documentation-unknown-command.cpp

 // RUN: %clang_cc1 -std=c++11 -fsyntax-only -Wdocumentation-unknown-command -verify %s
 // RUN: %clang_cc1 -std=c++11 -fsyntax-only -Werror -Wno-documentation-unknown-command %s
 
 // expected-warning@+1 {{unknown command tag name}}
 /// aaa \unknown
 int test_unknown_comand_1;
 
 // expected-warning@+1 {{unknown command tag name 'retur'; did you mean 'return'?}}
 /// \retur aaa
 int test_unknown_comand_2();
 
+// RUN: c-index-test -test-load-source all -Wdocumentation-unknown-command %s > /dev/null 2> %t.err
+// RUN: FileCheck < %t.err -check-prefix=CHECK-RANGE %s
+// CHECK-RANGE: warn-documentation-unknown-command.cpp:5:9:{5:9-5:17}: warning: unknown command tag name
+// CHECK-RANGE: warn-documentation-unknown-command.cpp:9:5:{9:5-9:11}: warning: unknown command tag name 'retur'; did you mean 'return'?