Generated enum schemas lack explicit types, causing conflict with isolatedDeclarations

[aaronshaf]

Issue Description

When using graphql-codegen-typescript-validation-schema in a TypeScript project with the isolatedDeclarations: true compiler option, the build fails. The root cause is that the Zod schemas generated for GraphQL enums do not have explicit type annotations, which is a requirement under isolatedDeclarations.

This forces us to either disable a valuable TypeScript compiler feature or avoid using the plugin for enum validation.

Environment

• graphql-codegen: 5.0.7
• graphql-codegen-typescript-validation-schema: 0.17.1
• typescript: 5.6.2
• zod: 3.25.67
• tsconfig.json with "isolatedDeclarations": true

Steps to Reproduce

1. Define a GraphQL schema with an enum:

enum Status {
  DRAFT
  PUBLISHED
  ARCHIVED
}

input PostInput {
  status: Status\!
}

2. Configure codegen.ts to use the typescript-validation-schema plugin:

import type { CodegenConfig } from '@graphql-codegen/cli';

const config: CodegenConfig = {
  schema: 'schema.graphql',
  generates: {
    './src/validation.ts': {
      plugins: [
        {
          'typescript-validation-schema': {
            schema: 'zod',
            // ... other options
          },
        },
      ],
    },
  },
};

export default config;

3. Run the code generator.

Problematic Output

The plugin generates the following code for the enum, which lacks a type annotation:

// validation.ts
import { z } from 'zod';

export const StatusSchema = z.enum(['DRAFT', 'PUBLISHED', 'ARCHIVED']);

Expected Output

For compatibility with isolatedDeclarations, the generated code should include an explicit type annotation:

// validation.ts
import { z } from 'zod';

export const StatusSchema: z.ZodEnum<["DRAFT", "PUBLISHED", "ARCHIVED"]> = z.enum(['DRAFT', 'PUBLISHED', 'ARCHIVED']);

Compiler Error

When another file imports StatusSchema, the TypeScript compiler throws an error:

error TS9023: Variable 'StatusSchema' must have an explicit type annotation with --isolatedDeclarations.

Suggested Solution

The plugin should be updated to add explicit z.ZodEnum<...> type annotations to all exported enum schemas it generates. This would make the output compatible with modern TypeScript project configurations that enable isolatedDeclarations.