[clang] [clang-tools-extra] [clangd] Add InsertReplaceEdit for code completion (PR #187623)

[via cfe-commits]

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@@ -2232,16 +2274,55 @@ CompletionPrefix guessCompletionPrefix(llvm::StringRef Content,
   return Result;
 }
 
+// If Offset is inside what looks like argument comment (e.g.
+// "/*^*/" or "/* foo = ^*/"), returns the offset pointing past the closing
+// "*/".
+static std::optional<unsigned>
+maybeFunctionArgumentCommentEnd(const PathRef FileName, const unsigned Offset,
+                                const llvm::StringRef Content,
+                                const LangOptions &LangOpts) {
+  if (Offset > Content.size())
+    return std::nullopt;
+
+  SourceManagerForFile FileSM(FileName, Content);
+  const SourceManager &SM = FileSM.get();
+  const SourceLocation Cursor =
+      SM.getComposedLoc(SM.getMainFileID(), static_cast<unsigned>(Offset));
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timon-ul wrote:

Why do we have a `static_cast` here?

https://github.com/llvm/llvm-project/pull/187623