[clang] [clang][Python] Apply type annotations to Python (PR #173845)

[Vlad Serebrennikov via cfe-commits]

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@@ -196,28 +205,26 @@ class TranslationUnitSaveError(Exception):
 
     # Indicates that an unknown error occurred. This typically indicates that
     # I/O failed during save.
-    ERROR_UNKNOWN = 1
+    ERROR_UNKNOWN: int = 1
 
     # Indicates that errors during translation prevented saving. The errors
     # should be available via the TranslationUnit's diagnostics.
-    ERROR_TRANSLATION_ERRORS = 2
-
+    ERROR_TRANSLATION_ERRORS: int = 2
     # Indicates that the translation unit was somehow invalid.
-    ERROR_INVALID_TU = 3
+    ERROR_INVALID_TU: int = 3
 
-    def __init__(self, enumeration, message):
+    def __init__(self, enumeration: int, message: str) -> None:
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Endilll wrote:

Having annotations on parameters is generally good, even if this is not a user-facing constructor and I have questions about taking an `int` here and calling it `enumeration`. But what value does `-> None` has on `__init__` functions?

https://github.com/llvm/llvm-project/pull/173845