Added support for several "type" metadata fields that are accessible …

…on classes that derive from type. This includes `__subclasses__`, `__module__`, etc.
microsoft · Jun 25, 2020 · 0c3a917 · 0c3a917
1 parent 44f32e8
commit 0c3a917
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Showing 5 changed files with 50 additions and 3 deletions.
diff --git a/server/src/analyzer/binder.ts b/server/src/analyzer/binder.ts
@@ -331,10 +331,21 @@ export class Binder extends ParseTreeWalker {
             // Note that __class__, __dict__ and __doc__ are skipped here
             // because the builtins.pyi type stub declares these in the
             // 'object' class.
+            this._addBuiltInSymbolToCurrentScope('__base__', node, 'Any');
+            this._addBuiltInSymbolToCurrentScope('__bases__', node, 'Any');
+            this._addBuiltInSymbolToCurrentScope('__basicsize__', node, 'int');
+            this._addBuiltInSymbolToCurrentScope('__dict__', node, 'Dict[str, Any]');
+            this._addBuiltInSymbolToCurrentScope('__dictoffset__', node, 'int');
+            this._addBuiltInSymbolToCurrentScope('__flags__', node, 'int');
+            this._addBuiltInSymbolToCurrentScope('__itemsize__', node, 'int');
+            this._addBuiltInSymbolToCurrentScope('__module__', node, 'str');
+            this._addBuiltInSymbolToCurrentScope('__mro__', node, 'Any');
             this._addBuiltInSymbolToCurrentScope('__name__', node, 'str');
-            if (this._fileInfo.executionEnvironment.pythonVersion >= PythonVersion.V33) {
+            if (this._fileInfo.executionEnvironment.pythonVersion >= PythonVersion.V30) {
                 this._addBuiltInSymbolToCurrentScope('__qualname__', node, 'str');
+                this._addBuiltInSymbolToCurrentScope('__text_signature__', node, 'str');
             }
+            this._addBuiltInSymbolToCurrentScope('__subclasses__', node, 'Any');
 
             // Analyze the suite.
             this.walk(node.suite);

diff --git a/server/src/analyzer/declaration.ts b/server/src/analyzer/declaration.ts
@@ -38,7 +38,7 @@ export const enum DeclarationType {
     Alias,
 }
 
-export type IntrinsicType = 'Any' | 'str' | 'Iterable[str]' | 'class' | 'Dict[str, Any]';
+export type IntrinsicType = 'Any' | 'str' | 'int' | 'Iterable[str]' | 'class' | 'Dict[str, Any]';
 
 export interface DeclarationBase {
     // Category of this symbol (function, variable, etc.).

diff --git a/server/src/analyzer/typeEvaluator.ts b/server/src/analyzer/typeEvaluator.ts
@@ -10891,12 +10891,18 @@ export function createTypeEvaluator(importLookup: ImportLookup, printTypeFlags:
                     const classTypeInfo = getTypeOfClass(classNode);
                     return classTypeInfo ? classTypeInfo.classType : undefined;
                 }
+
                 const strType = getBuiltInObject(declaration.node, 'str');
-                if (strType.category === TypeCategory.Object) {
+                const intType = getBuiltInObject(declaration.node, 'int');
+                if (intType.category === TypeCategory.Object && strType.category === TypeCategory.Object) {
                     if (declaration.intrinsicType === 'str') {
                         return strType;
                     }
 
+                    if (declaration.intrinsicType === 'int') {
+                        return intType;
+                    }
+
                     if (declaration.intrinsicType === 'Iterable[str]') {
                         const iterableType = getBuiltInType(declaration.node, 'Iterable');
                         if (iterableType.category === TypeCategory.Class) {

diff --git a/server/src/tests/checker.test.ts b/server/src/tests/checker.test.ts
@@ -903,6 +903,12 @@ test('Classes2', () => {
     validateResults(analysisResults, 2);
 });
 
+test('Classes3', () => {
+    const analysisResults = TestUtils.typeAnalyzeSampleFiles(['classes3.py']);
+
+    validateResults(analysisResults, 1);
+});
+
 test('Mro1', () => {
     const analysisResults = TestUtils.typeAnalyzeSampleFiles(['mro1.py']);
 

diff --git a/server/src/tests/samples/classes3.py b/server/src/tests/samples/classes3.py
@@ -0,0 +1,24 @@
+# This sample tests that various class variables (as defined in
+# the type metaclass) are accessible without a type error.
+
+
+class TestClass:
+    pass
+
+
+base = TestClass.__base__
+basic_size = TestClass.__basicsize__
+dict = TestClass.__dict__
+dict_offset = TestClass.__dictoffset__
+flags = TestClass.__flags__
+item_size = TestClass.__itemsize__
+module = TestClass.__module__
+mro = TestClass.__mro__
+name = TestClass.__name__
+qualname = TestClass.__qualname__
+text_signature = TestClass.__text_signature__
+subclasses = TestClass.__subclasses__
+
+
+# This should generate an error
+dummy = TestClass.__dummy__