[analyzer] Fix incorrect link to "note" diagnostics in HTML output

[gruuprasad]

Summary

IDs of the note list start from 1. Link generated for each note started with index 0 i.e #Note0, #Note1 and so on.
As a result, first link ("#Note0") was invalid, subsequent links pointed at wrong note.
Now, generated links to the notes start with index 1 i.e (#Note1, #Note2 and so on.

github issue link: https://github.com/llvm/llvm-project/issues/64054
Tested generated HTML output manually for correctness.

[steakhal]

Could you please add a test for the patch?

[gruuprasad]

Sure, Initially I didn't find the folder StaticAnalysis in the clang/test folder, found that relevant tests are in test/Analysis.

[steakhal]

In D156724#4547891, @gruuprasad wrote:

Sure, Initially I didn't find the folder StaticAnalysis in the clang/test folder, found that relevant tests are in test/Analysis.

Correct, thanks!

[gruuprasad]

Add test

[gruuprasad]

I went through the build logs, but failed test (Clang :: Driver/fsanitize.c) seems to be irrelevant to the changes in this patch.

clang/lib/StaticAnalyzer/Core/HTMLDiagnostics.cpp

596–600

git clang-format suggests formatting this block of code, but kept them as is since I didn't modify this part.

[steakhal]

Looks correct.
Please merge it.

[gruuprasad]

@steakhal, ok, this is my first contribution, I don't have the commit access yet.
Can you please merge this?

[steakhal]

In D156724#4556774, @gruuprasad wrote:

@steakhal, ok, this is my first contribution, I don't have the commit access yet.
Can you please merge this?

What should be the commit author?

[gruuprasad]

Email:[e-mail]
GitHub username: gruuprasad
Either of these fine.

Thank you!

clang/lib/StaticAnalyzer/Core/HTMLDiagnostics.cpp

// Add the name of the file as an <h1> tag.
     // The navigation across the extra notes pieces.
     unsigned NumExtraPieces = 0;
     for (const auto &Piece : path) {
       if (const auto *P = dyn_cast<PathDiagnosticNotePiece>(Piece.get())) {
         int LineNumber =
             P->getLocation().asLocation().getExpansionLineNumber();
         int ColumnNumber =
             P->getLocation().asLocation().getExpansionColumnNumber();
+        ++NumExtraPieces;
         os << "<tr><td class=\"rowname\">Note:</td><td>"
            << "<a href=\"#Note" << NumExtraPieces << "\">line "
            << LineNumber << ", column " << ColumnNumber << "</a><br />"
            << P->getString() << "</td></tr>";
-        ++NumExtraPieces;
       }
     }
 
     // Output any other meta data.
 
     for (const std::string &Metadata :
          llvm::make_range(D.meta_begin(), D.meta_end())) {
       os << "<tr><td></td><td>" << html::EscapeText(Metadata) << "</td></tr>\n";
     }