fix: Correctly support ClassDeclarations without identifier

src/__tests__/__snapshots__/main-test.js.snap

@@ -1801,6 +1801,22 @@ Object {
 }
 `;
 
+exports[`main fixtures processes component "component_41.tsx" without errors 1`] = `
+Object {
+  "description": "",
+  "methods": Array [],
+  "props": Object {
+    "value": Object {
+      "description": "",
+      "required": true,
+      "tsType": Object {
+        "name": "string",
+      },
+    },
+  },
+}
+`;
+
 exports[`main fixtures processes component "flow-export-type.js" without errors 1`] = `
 Object {
   "description": "This is a Flow class component",

src/__tests__/fixtures/component_41.tsx

@@ -0,0 +1,11 @@
+import * as React from 'react';
+
+interface IProps {
+  value: string;
+}
+
+export default class extends React.Component<IProps> {
+  render() {
+    return <div className='s-c-z-example'/>;
+  }
+}

src/handlers/__tests__/displayNameHandler-test.js

@@ -141,6 +141,17 @@ describe('defaultPropsHandler', () => {
   });
 
   describe('ClassDeclaration', () => {
+    it('ignores classes without name', () => {
+      const definition = statement(`
+        export default class {
+        }
+      `).get('declaration');
+      expect(() =>
+        displayNameHandler(documentation, definition, noopImporter),
+      ).not.toThrow();
+      expect(documentation.displayName).not.toBeDefined();
+    });
+
     it('considers the class name', () => {
       const definition = statement(`
         class Foo {

src/handlers/displayNameHandler.js

@@ -26,8 +26,9 @@ export default function displayNameHandler(
     // Function and class declarations need special treatment. The name of the
     // function / class is the displayName
     if (
-      t.ClassDeclaration.check(path.node) ||
-      t.FunctionDeclaration.check(path.node)
+      (t.ClassDeclaration.check(path.node) ||
+        t.FunctionDeclaration.check(path.node)) &&
+      path.node.id != null
     ) {
       documentation.set('displayName', getNameOrValue(path.get('id')));
     } else if (