[clang] [clang] Add Bytes/Column types to TextDiagnostic (PR #165541)

[via cfe-commits]

================
@@ -1379,35 +1440,36 @@ void TextDiagnostic::emitSnippetAndCaret(
     std::string SourceLine(LineStart, LineEnd);
     // Remove trailing null bytes.
     while (!SourceLine.empty() && SourceLine.back() == '\0' &&
-           (LineNo != CaretLineNo || SourceLine.size() > CaretColNo))
+           (LineNo != CaretLineNo ||
+            SourceLine.size() > static_cast<size_t>(CaretByte.V)))
       SourceLine.pop_back();
 
     // Build the byte to column map.
-    const SourceColumnMap sourceColMap(SourceLine, DiagOpts.TabStop);
+    const SourceColumnMap SourceColMap(SourceLine, DiagOpts.TabStop);
 
     std::string CaretLine;
     // Highlight all of the characters covered by Ranges with ~ characters.
     for (const auto &LR : LineRanges) {
       if (LR.LineNo == LineNo)
-        highlightRange(LR, sourceColMap, CaretLine);
+        highlightRange(LR, SourceColMap, CaretLine);
     }
 
     // Next, insert the caret itself.
     if (CaretLineNo == LineNo) {
-      size_t Col = sourceColMap.byteToContainingColumn(CaretColNo - 1);
-      CaretLine.resize(std::max(Col + 1, CaretLine.size()), ' ');
-      CaretLine[Col] = '^';
+      Columns Col = SourceColMap.byteToContainingColumn(CaretByte.prev());
+      CaretLine.resize(std::max((size_t)Col.V + 1, CaretLine.size()), ' ');
----------------
Sirraide wrote:

```suggestion
      CaretLine.resize(std::max(static_cast<size_t>(Col.V) + 1, CaretLine.size()), ' ');
```

https://github.com/llvm/llvm-project/pull/165541