Mock type naming inconsistency in version 1.23.0 - Cannot find type in scope

[hoffsilva-agendrix]

Summary

Bug Report

Environment

• Apollo iOS Version: 1.23.0
• Xcode Version: 16.3
• Swift Version: 6.1

Description

After upgrading from Apollo iOS 1.(16...22).0 to 1.23.0, the generated test mocks produce compilation errors due to type naming inconsistencies.

Analysis

This issue appears to be a regression introduced by a new feature in version 1.23.0:

Added requireNonOptionalMockFields flag to ApolloCodegenConfiguration.OutputOptions. (#669): Added new flag to codegen output options to allow having non-optional fields in the test mocks if desired. Thank you to @dwroth for the contribution.

While this feature aims to improve mock generation, it seems to have introduced an unintended side
effect in the type naming logic.

What changed:

• Version 1.22.0 and earlier: Mock fields used optional types with nil defaults: SwiftMock<Type>? = nil
• Version 1.23.0: Mock fields now use non-optional types with constructor defaults: SwiftMock<Type> = Mock<type>()

The issue:

The new implementation has inconsistent type naming where:

• The parameter declaration uses one naming convention: SwiftMock<Acknowledge_billboard_threadPayload>
• The default constructor uses a different convention: SwiftMock<acknowledge_billboard_threadPayload>()

It appears that the mock object creation should use the same type as the parameter declaration (SwiftMock<Acknowledge_billboard_threadPayload>() instead of SwiftMock<acknowledge_billboard_threadPayload>()), but the code generation is incorrectly applying different naming strategies to the parameter type vs. the constructor type.

Since the snake_case version doesn't exist, the compiler throws a "Cannot find type in scope"
error.

This appears to be an oversight in the implementation rather than an intentional breaking change, as the same GraphQL schema that worked perfectly in 1.22.0 now fails to compile in 1.23.0 with default configurations.

Through systematic testing, we confirmed:

• 1.16.0 to 1.22.0: All work correctly
• 1.23.0: Introduces this bug

Version

1.23.0

Steps to reproduce the behavior

1. Upgrade Apollo iOS from 1.(16...22).0 to 1.23.0
2. Generate GraphQL code using apollo-ios-cli generate
3. Try to build the project

Expected Behavior

The generated mock code should compile without errors, as it did in versions 1.(16...22).0 .

Actual Behavior

Compilation fails with errors like:

Cannot find type 'acknowledge_billboard_threadPayload' in scope
Code Examples

Generated in 1.(16...22).0 (Working):

public extension Mock where O == Mutation {
  convenience init(
    acknowledgeBillboardThread: Mock<Acknowledge_billboard_threadPayload>? = nil,
    // ...
  )
}

Generated in 1.23.0 (Broken):

public extension Mock where O == Mutation {
  convenience init(
    acknowledgeBillboardThread: Mock<Acknowledge_billboard_threadPayload> =
Mock<acknowledge_billboard_threadPayload>(),
    // ...
  )
}

Logs

Anything else?

No response

[BobaFetters]

@hoffsilva-agendrix Thanks for the detailed report! We will get this fixed and out into a patch release soon.

[dwroth]

I see what's going on here. I should be able to get a fix to you shortly. It's specifically an issue with type names that start with lower cased letters, which we don't have in any of our tests. I'll add a test case to prevent regressions as well.

[dwroth]

This should do it: apollographql/apollo-ios-dev#712

[dwroth]

Thanks for the clear issue report, @hoffsilva-agendrix. It made spotting the bug really easy.

[BobaFetters]

The fix for this is merged and can go out in our next release.

[github-actions]

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[hoffsilva-agendrix]

Thank you @dwroth and @BobaFetters for the quick response and solution!

I appreciate the team's commitment to improving the developer experience. This will definitely help iOS developers who are coming from Apollo's other client implementations.

Thanks again for the great work! 🙏