[clang] [libclang/python] Fix bug in `SourceRange.__contains__`, add tests (PR #101802)

[Vlad Serebrennikov via cfe-commits]

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@@ -50,6 +50,17 @@ unsigned clang_equalLocations(CXSourceLocation loc1, CXSourceLocation loc2) {
           loc1.int_data == loc2.int_data);
 }
 
+unsigned clang_lessThanLocations(CXSourceLocation loc1, CXSourceLocation loc2) {
+  const SourceLocation Loc1 = SourceLocation::getFromRawEncoding(loc1.int_data);
+  const SourceLocation Loc2 = SourceLocation::getFromRawEncoding(loc2.int_data);
+
+  const SourceManager &SM =
+      *static_cast<const SourceManager *>(loc1.ptr_data[0]);
+  // Use the appropriate SourceManager method here rather than operator< because
+  // ordering is meaningful only if LHS and RHS have the same FileID
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Endilll wrote:

Can you also remove the following TODO https://github.com/llvm/llvm-project/blob/2b959bd7f21bc7550a99fb160997002b7e4f1b62/clang/lib/Basic/SourceManager.cpp#L2041-L2042
because we now depend on this check, and update it's documentation to reflect that? It would also make sense to reference libclang as a user where such "impossible" inputs can come from.

https://github.com/llvm/llvm-project/pull/101802