feat(type-generator): support properties with type array and undefine…

…d items (#1203)

If a property is of `type: array` but does not have `items` or `items`
are not of `object` type, then code generation fails.

Instead of failing, this PR would let it fallback to array of `any` item
types.

Fixes #1194

---------

Signed-off-by: Vinayak Kukreja <vinakuk@amazon.com>

src/type-generator.ts

@@ -535,7 +535,8 @@ export class TypeGenerator {
 
   private typeForArray(propertyFqn: string, def: JSONSchema4): EmittedType {
     if (!def.items || typeof(def.items) !== 'object') {
-      throw new Error(`unsupported array type ${def.items}`);
+      // Falling back to an array of any type
+      def.items = {};
     }
 
     return this.typeForProperty(propertyFqn, def.items);

test/tojson.test.ts

@@ -122,6 +122,39 @@ describe('arrays', () => {
     });
   });
 
+  test('without items', () => {
+    const toJson = generateToJson({
+      properties: {
+        ArrayProp: { type: 'array' },
+      },
+    });
+
+    expect(toJson({
+      arrayProp: ['bello', { foo: 88, bar: 'world' }],
+    })).toStrictEqual({
+      ArrayProp: ['bello', { foo: 88, bar: 'world' }],
+    });
+  });
+
+  test('with items', () => {
+    const toJson = generateToJson({
+      properties: {
+        ArrayProp: {
+          type: 'array',
+          items: {
+            type: 'string',
+          },
+        },
+      },
+    });
+
+    expect(toJson({
+      arrayProp: ['bello', { foo: 88, bar: 'world' }],
+    })).toStrictEqual({
+      ArrayProp: ['bello', { foo: 88, bar: 'world' }],
+    });
+  });
+
 });
 
 test('any', () => {