Fix/default props

src/__tests__/data/ComponentWithReferencedDefaultProps.tsx

@@ -0,0 +1,51 @@
+import * as React from 'react';
+
+/** IComponentWithDefaultPropsProps props */
+export interface IComponentWithDefaultPropsProps {
+  /**
+   * sample with default value
+   * @default hello
+   */
+  sampleDefaultFromJSDoc: 'hello' | 'goodbye';
+  /** sampleTrue description */
+  sampleTrue?: boolean;
+  /** sampleFalse description */
+  sampleFalse?: boolean;
+  /** sampleString description */
+  sampleString?: string;
+  /** sampleObject description */
+  sampleObject?: { [key: string]: any };
+  /** sampleNull description */
+  sampleNull?: null;
+  /** sampleUndefined description */
+  sampleUndefined?: any;
+  /** sampleNumber description */
+  sampleNumber?: number;
+}
+
+const defaultProps: Partial<IComponentWithDefaultPropsProps> = {
+  sampleFalse: false,
+  sampleNull: null,
+  sampleNumber: -1,
+  // prettier-ignore
+  sampleObject: { a: '1', b: 2, c: true, d: false, e: undefined, f: null, g: { a: '1' } },
+  sampleString: 'hello',
+  sampleTrue: true,
+  sampleUndefined: undefined
+};
+
+const defaultPropsReference = defaultProps;
+
+/** ComponentWithDefaultProps description */
+export class ComponentWithDefaultProps extends React.Component<
+  IComponentWithDefaultPropsProps,
+  {}
+> {
+  static defaultProps: Partial<
+    IComponentWithDefaultPropsProps
+  > = defaultPropsReference;
+
+  public render() {
+    return <div>test</div>;
+  }
+}

src/__tests__/parser.ts

@@ -176,8 +176,8 @@ describe('parser', () => {
     });
   });
 
-  it('should parse react component with default props', () => {
-    check('ComponentWithDefaultProps', {
+  describe('component with default props', () => {
+    const expectation = {
       ComponentWithDefaultProps: {
         sampleDefaultFromJSDoc: {
           defaultValue: 'hello',
@@ -209,6 +209,14 @@ describe('parser', () => {
           type: 'any'
         }
       }
+    };
+
+    it('should parse defined props', () => {
+      check('ComponentWithDefaultProps', expectation);
+    });
+
+    it('should parse referenced props', () => {
+      check('ComponentWithReferencedDefaultProps', expectation);
     });
   });
 

src/parser.ts

@@ -408,20 +408,41 @@ class Parser {
     if (!possibleStatements.length) {
       return {};
     }
+
     const statement = possibleStatements[0];
+
     if (statementIsClassDeclaration(statement) && statement.members.length) {
       const possibleDefaultProps = statement.members.filter(
         member => member.name && getPropertyName(member.name) === 'defaultProps'
       );
+
       if (!possibleDefaultProps.length) {
         return {};
       }
+
       const defaultProps = possibleDefaultProps[0];
-      const { initializer } = defaultProps as ts.PropertyDeclaration;
-      const { properties } = initializer as ts.ObjectLiteralExpression;
+      let initializer = (defaultProps as ts.PropertyDeclaration).initializer;
+      let properties = (initializer as ts.ObjectLiteralExpression).properties;
+
+      while (ts.isIdentifier(initializer as ts.Identifier)) {
+        const defaultPropsReference = this.checker.getSymbolAtLocation(
+          initializer as ts.Node
+        );
+        if (defaultPropsReference) {
+          const declarations = defaultPropsReference.getDeclarations();
+
+          if (declarations) {
+            initializer = (declarations[0] as ts.VariableDeclaration)
+              .initializer;
+            properties = (initializer as ts.ObjectLiteralExpression).properties;
+          }
+        }
+      }
+
       const propMap = getPropMap(properties as ts.NodeArray<
         ts.PropertyAssignment
       >);
+
       return propMap;
     } else if (statementIsStateless(statement)) {
       let propMap = {};