chore: some more tests and comments

Signed-off-by: blam <ben@blam.sh>

packages/frontend-plugin-api/src/wiring/createExtension.test.ts

@@ -599,7 +599,9 @@ describe('createExtension', () => {
         attachTo: { id: 'root', input: 'blob' },
         output: [stringDataRef],
         inputs: {
-          test: createExtensionInput([stringDataRef], { singleton: true }),
+          test: createExtensionInput([stringDataRef], {
+            singleton: true,
+          }),
         },
         config: {
           schema: {
@@ -641,5 +643,31 @@ describe('createExtension', () => {
 
       expect(true).toBe(true);
     });
+
+    it('should allow overriding the factory function and calling the original factory', () => {
+      const testExtension = createExtension({
+        namespace: 'test',
+        attachTo: { id: 'root', input: 'blob' },
+        output: [stringDataRef],
+        config: {
+          schema: {
+            foo: z => z.string().optional(),
+          },
+        },
+        factory() {
+          return [stringDataRef('default')];
+        },
+      });
+
+      testExtension.override({
+        factory(originalFactory) {
+          const response = originalFactory();
+
+          const foo: string = response.get(stringDataRef);
+
+          return [stringDataRef(`foo-${foo}-override`)];
+        },
+      });
+    });
   });
 });

packages/frontend-plugin-api/src/wiring/createExtension.ts

@@ -274,6 +274,8 @@ export type OverrideExtensionOptions<
         [key in keyof TConfigSchema]: z.infer<ReturnType<TConfigSchema[key]>>;
       };
       inputs?: Expand<ResolvedExtensionInputs<TInputs>>;
+      // todo(blam): Think this is better as a DataContainer instead
+      // should probably update that everywhere.
     }) => Iterable<UOriginalFactoryOutput>,
     context: {
       node: AppNode;
@@ -292,8 +294,11 @@ export type OverrideExtensionOptions<
       inputs: Expand<ResolvedExtensionInputs<TInputs>>;
     },
   ): Iterable<UFactoryOverrideOutput>;
-  // todo(blam): need to verify that the outputs are meged properly.
-} & VerifyExtensionFactoryOutput<UOutput, UFactoryOverrideOutput>;
+  // todo(blam): need to verify that the outputs are merged and verified properly.
+} & VerifyExtensionFactoryOutput<
+  UOutput & UFactoryOverrideOutput,
+  UFactoryOverrideOutput
+>;
 
 /** @public */
 export type OverridableExtension<