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

[Vlad Serebrennikov via cfe-commits]

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@@ -386,6 +386,10 @@ def __contains__(self, other):
         # same file, in between lines
         if self.start.line < other.line < self.end.line:
             return True
+        # between columns in one-liner range
+        elif self.start.line == other.line == self.end.line:
----------------
Endilll wrote:

How about we follow the `SourceRange::fullyContains`? In other words, expose `SourceLocation::operator<` to enable ordering of source locations, and leverage that in `SourceRange.__contains__`. I expect the latter to become much simpler.

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