fix(ai): return transformed array output elements

Author: he-yufeng

packages/ai/src/generate-object/generate-object.test.ts

@@ -906,6 +906,33 @@ describe('generateObject', () => {
       }
     `);
     });
+
+    it('should return transformed element values', async () => {
+      const model = new MockLanguageModelV4({
+        doGenerate: {
+          ...dummyResponseValues,
+          content: [
+            {
+              type: 'text',
+              text: JSON.stringify({
+                elements: [{ content: 'element 1' }],
+              }),
+            },
+          ],
+        },
+      });
+
+      const result = await generateObject({
+        model,
+        schema: z.object({
+          content: z.string().transform(value => value.toUpperCase()),
+        }),
+        output: 'array',
+        prompt: 'prompt',
+      });
+
+      expect(result.object).toEqual([{ content: 'ELEMENT 1' }]);
+    });
   });
 
   describe('output = "enum"', () => {

packages/ai/src/generate-object/output-strategy.ts

@@ -239,16 +239,19 @@ const arrayOutputStrategy = <ELEMENT>(
       }
 
       const inputArray = value.elements as Array<JSONObject>;
+      const resultArray: Array<ELEMENT> = [];
 
       // check that each element in the array is of the correct type:
       for (const element of inputArray) {
         const result = await safeValidateTypes({ value: element, schema });
         if (!result.success) {
           return result;
         }
+
+        resultArray.push(result.value);
       }
 
-      return { success: true, value: inputArray as Array<ELEMENT> };
+      return { success: true, value: resultArray };
     },
 
     createElementStream(

packages/ai/src/generate-text/output.test.ts

@@ -322,6 +322,21 @@ describe('Output.array', () => {
       expect(result).toStrictEqual([{ content: 'test' }]);
     });
 
+    it('should return transformed element values', async () => {
+      const arrayWithTransform = array({
+        element: z.object({
+          content: z.string().transform(value => value.toUpperCase()),
+        }),
+      });
+
+      const result = await arrayWithTransform.parseCompleteOutput(
+        { text: `{ "elements": [{ "content": "test" }] }` },
+        context,
+      );
+
+      expect(result).toStrictEqual([{ content: 'TEST' }]);
+    });
+
     it('should throw NoObjectGeneratedError when parsing fails', async () => {
       try {
         await array1.parseCompleteOutput({ text: '{ broken json' }, context);

packages/ai/src/generate-text/output.ts

@@ -278,6 +278,7 @@ export const array = <ELEMENT>({
         });
       }
 
+      const parsedElements: Array<ELEMENT> = [];
       for (const element of outerValue.elements) {
         const validationResult = await safeValidateTypes({
           value: element,
@@ -294,9 +295,11 @@ export const array = <ELEMENT>({
             finishReason: context.finishReason,
           });
         }
+
+        parsedElements.push(validationResult.value);
       }
 
-      return outerValue.elements as Array<ELEMENT>;
+      return parsedElements;
     },
 
     async parsePartialOutput({ text }: { text: string }) {