python: add bindings for children of diagnostics

This exposes the Clang API bindings clang_getChildDiagnostics (which returns a
CXDiagnosticSet) and clang_getNumDiagnosticsInSet / clang_getDiagnosticInSet (to
traverse the CXDiagnosticSet), and adds a helper children property in the Python
Diagnostic wrapper.

Also, this adds the missing OVERLOAD_CANDIDATE (700) cursor type.

Patch by Hanson Wang!

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@268167 91177308-0d34-0410-b5e6-96231b3b80d8

bindings/python/clang/cindex.py

@@ -359,6 +359,23 @@ def __getitem__(self, key):
 
         return FixItIterator(self)
 
+    @property
+    def children(self):
+        class ChildDiagnosticsIterator:
+            def __init__(self, diag):
+                self.diag_set = conf.lib.clang_getChildDiagnostics(diag)
+
+            def __len__(self):
+                return int(conf.lib.clang_getNumDiagnosticsInSet(self.diag_set))
+
+            def __getitem__(self, key):
+                diag = conf.lib.clang_getDiagnosticInSet(self.diag_set, key)
+                if not diag:
+                    raise IndexError
+                return Diagnostic(diag)
+
+        return ChildDiagnosticsIterator(self)
+
     @property
     def category_number(self):
         """The category number for this diagnostic or 0 if unavailable."""
@@ -1120,6 +1137,9 @@ def __repr__(self):
 # A type alias template declaration
 CursorKind.TYPE_ALIAS_TEMPLATE_DECL = CursorKind(601)
 
+# A code completion overload candidate.
+CursorKind.OVERLOAD_CANDIDATE = CursorKind(700)
+
 ### Template Argument Kinds ###
 class TemplateArgumentKind(BaseEnumeration):
     """
@@ -3053,6 +3073,10 @@ def cursor(self):
    Type,
    Type.from_result),
 
+  ("clang_getChildDiagnostics",
+   [Diagnostic],
+   c_object_p),
+
   ("clang_getCompletionAvailability",
    [c_void_p],
    c_int),
@@ -3173,6 +3197,10 @@ def cursor(self):
    _CXString,
    _CXString.from_result),
 
+  ("clang_getDiagnosticInSet",
+   [c_object_p, c_uint],
+   c_object_p),
+
   ("clang_getDiagnosticLocation",
    [Diagnostic],
    SourceLocation),
@@ -3274,6 +3302,10 @@ def cursor(self):
    [c_object_p],
    c_uint),
 
+  ("clang_getNumDiagnosticsInSet",
+   [c_object_p],
+   c_uint),
+
   ("clang_getNumElements",
    [Type],
    c_longlong),

bindings/python/tests/cindex/test_diagnostics.py

@@ -80,3 +80,15 @@ def test_diagnostic_option():
 
     assert d.option == '-Wunused-parameter'
     assert d.disable_option == '-Wno-unused-parameter'
+
+def test_diagnostic_children():
+    tu = get_tu('void f(int x) {} void g() { f(); }')
+    assert len(tu.diagnostics) == 1
+    d = tu.diagnostics[0]
+
+    children = d.children
+    assert len(children) == 1
+    assert children[0].severity == Diagnostic.Note
+    assert children[0].spelling.endswith('declared here')
+    assert children[0].location.line == 1
+    assert children[0].location.column == 1