[libclang/python] Add type annotations for code completion classes (#140539)

This fully annotates the code completion classes (CompletionChunk,
CompletionString, CodeCompletionResult, CodeCompletionResults and
CCRStructure) resolving 59 strict typing errors as the next step towards
#76664

Author: DeinAlptraum

clang/bindings/python/clang/cindex.py

@@ -110,6 +110,7 @@
         "tuple[str, Optional[list[Any]], Any]",
         "tuple[str, Optional[list[Any]], Any, Callable[..., Any]]",
     ]
+    CObjP: TypeAlias = _Pointer[Any]
 
     TSeq = TypeVar("TSeq", covariant=True)
 
@@ -2981,25 +2982,25 @@ class _CXUnsavedFile(Structure):
 
 class CompletionChunk:
     class Kind:
-        def __init__(self, name):
+        def __init__(self, name: str):
             self.name = name
 
-        def __str__(self):
+        def __str__(self) -> str:
             return self.name
 
-        def __repr__(self):
+        def __repr__(self) -> str:
             return "<ChunkKind: %s>" % self
 
-    def __init__(self, completionString, key):
+    def __init__(self, completionString: CObjP, key: int):
         self.cs = completionString
         self.key = key
         self.__kindNumberCache = -1
 
-    def __repr__(self):
+    def __repr__(self) -> str:
         return "{'" + self.spelling + "', " + str(self.kind) + "}"
 
     @CachedProperty
-    def spelling(self):
+    def spelling(self) -> str:
         if self.__kindNumber in SPELLING_CACHE:
             return SPELLING_CACHE[self.__kindNumber]
         return _CXString.from_result(
@@ -3010,38 +3011,38 @@ def spelling(self):
     # apparently still significantly faster. Please profile carefully if you
     # would like to add CachedProperty back.
     @property
-    def __kindNumber(self):
+    def __kindNumber(self) -> int:
         if self.__kindNumberCache == -1:
             self.__kindNumberCache = conf.lib.clang_getCompletionChunkKind(
                 self.cs, self.key
             )
         return self.__kindNumberCache
 
     @CachedProperty
-    def kind(self):
+    def kind(self) -> Kind:
         return completionChunkKindMap[self.__kindNumber]
 
     @CachedProperty
-    def string(self):
+    def string(self) -> CompletionString | None:
         res = conf.lib.clang_getCompletionChunkCompletionString(self.cs, self.key)
 
         if not res:
             return None
         return CompletionString(res)
 
-    def isKindOptional(self):
+    def isKindOptional(self) -> bool:
         return self.__kindNumber == 0
 
-    def isKindTypedText(self):
+    def isKindTypedText(self) -> bool:
         return self.__kindNumber == 1
 
-    def isKindPlaceHolder(self):
+    def isKindPlaceHolder(self) -> bool:
         return self.__kindNumber == 3
 
-    def isKindInformative(self):
+    def isKindInformative(self) -> bool:
         return self.__kindNumber == 4
 
-    def isKindResultType(self):
+    def isKindResultType(self) -> bool:
         return self.__kindNumber == 15
 
 
@@ -3081,39 +3082,39 @@ def __str__(self):
         def __repr__(self):
             return "<Availability: %s>" % self
 
-    def __len__(self):
+    def __len__(self) -> int:
         return self.num_chunks
 
     @CachedProperty
-    def num_chunks(self):
+    def num_chunks(self) -> int:
         return conf.lib.clang_getNumCompletionChunks(self.obj)  # type: ignore [no-any-return]
 
-    def __getitem__(self, key):
+    def __getitem__(self, key: int) -> CompletionChunk:
         if self.num_chunks <= key:
             raise IndexError
         return CompletionChunk(self.obj, key)
 
     if TYPE_CHECKING:
         # Defining __getitem__ and __len__ is enough to make an iterable
         # but the typechecker doesn't understand that.
-        def __iter__(self):
+        def __iter__(self) -> Iterator[CompletionChunk]:
             for i in range(len(self)):
                 yield self[i]
 
     @property
-    def priority(self):
+    def priority(self) -> int:
         return conf.lib.clang_getCompletionPriority(self.obj)  # type: ignore [no-any-return]
 
     @property
-    def availability(self):
+    def availability(self) -> CompletionChunk.Kind:
         res = conf.lib.clang_getCompletionAvailability(self.obj)
         return availabilityKinds[res]
 
     @property
-    def briefComment(self):
+    def briefComment(self) -> str:
         return _CXString.from_result(conf.lib.clang_getCompletionBriefComment(self.obj))
 
-    def __repr__(self):
+    def __repr__(self) -> str:
         return (
             " | ".join([str(a) for a in self])
             + " || Priority: "
@@ -3136,44 +3137,47 @@ def __repr__(self):
 class CodeCompletionResult(Structure):
     _fields_ = [("cursorKind", c_int), ("completionString", c_object_p)]
 
-    def __repr__(self):
+    def __repr__(self) -> str:
         return str(CompletionString(self.completionString))
 
     @property
-    def kind(self):
+    def kind(self) -> CursorKind:
         return CursorKind.from_id(self.cursorKind)
 
     @property
-    def string(self):
+    def string(self) -> CompletionString:
         return CompletionString(self.completionString)
 
 
 class CCRStructure(Structure):
     _fields_ = [("results", POINTER(CodeCompletionResult)), ("numResults", c_int)]
 
-    def __len__(self):
+    results: NoSliceSequence[CodeCompletionResult]
+    numResults: int
+
+    def __len__(self) -> int:
         return self.numResults
 
-    def __getitem__(self, key):
+    def __getitem__(self, key: int) -> CodeCompletionResult:
         if len(self) <= key:
             raise IndexError
 
         return self.results[key]
 
 
 class CodeCompletionResults(ClangObject):
-    def __init__(self, ptr):
+    def __init__(self, ptr: _Pointer[CCRStructure]):
         assert isinstance(ptr, POINTER(CCRStructure)) and ptr
         self.ptr = self._as_parameter_ = ptr
 
-    def from_param(self):
+    def from_param(self) -> _Pointer[CCRStructure]:
         return self._as_parameter_
 
-    def __del__(self):
+    def __del__(self) -> None:
         conf.lib.clang_disposeCodeCompleteResults(self)
 
     @property
-    def results(self):
+    def results(self) -> CCRStructure:
         return self.ptr.contents
 
     @property