Expose handler type with preload on

[DZakh]

Fixes #540

Summary by CodeRabbit

• New Features

  • When preload_handlers is enabled, generated code now includes typed aliases for handler arguments, handlers, and contract registration. This improves type clarity, autocompletion, and integration in consumer projects. Behavior is unchanged when preload_handlers is disabled.

• Chores

  • Internal template output updated to emit explicit handler-related types only for preload_handlers-enabled generation, with no impact on public APIs.

[coderabbitai]

Walkthrough

The template for generated code now emits three type aliases in the preload_handlers branch: handlerArgs, handler, and contractRegister, replacing a previously empty output. The non-preload branch remains unchanged. No Rust public API signatures were modified; only generated string content was updated.

Changes

Cohort / File(s)	Summary
Codegen templates codegenerator/cli/src/hbs_templating/codegen_templates.rs	In the preload_handlers path, generated code now includes type aliases: handlerArgs = Internal.genericHandlerArgs<event, handlerContext, unit>, handler = Internal.genericHandler, and contractRegister = Internal.genericContractRegister<Internal.genericContractRegisterArgs<event, contractRegistrations>>. Non-preload path unchanged.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~10 minutes

Assessment against linked issues

Objective	Addressed	Explanation
Generate type for handlerArgs per event (#540)	❓	handlerArgs alias added, but per-event specificity is unclear from the template and only applied under preload_handlers.
Generate type for loaderArgs per event (#540)	❌	No loaderArgs type introduced.

Assessment against linked issues: Out-of-scope changes

Code Change	Explanation
Add contractRegister type alias in generated code (codegenerator/cli/src/hbs_templating/codegen_templates.rs)	Not requested by #540, which targets loaderArgs and handlerArgs only.
Add handler type alias in generated code (codegenerator/cli/src/hbs_templating/codegen_templates.rs)	#540 does not mention introducing a handler alias; scope is limited to args types.

Possibly related PRs

• Generate type for loaderArgs and handlerArgs per event #540 — Also modifies codegen_templates.rs to introduce per-event handlerArgs; closely aligned in purpose and location.

Poem

A nibble of types in fields of code,
I twitch my ears at the preload mode.
HandlerArgs hop in, a tidy trio appears,
But where’s loaderArgs? I thump my fears.
Still, springy steps on the template track—
One hop forward, one to circle back. 🐇

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• Commit unit tests in branch dz/expose-handler-type-with-preload

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[coderabbitai]

Actionable comments posted: 0

🧹 Nitpick comments (1)

codegenerator/cli/src/hbs_templating/codegen_templates.rs (1)

462-469: Preload branch types look correct; consider also exposing loaderArgs and confirm 'unit is the intended loader return.

• Emitting handlerArgs, handler, and contractRegister under preload_handlers is aligned with the PR goal and seems correct.
• Given Issue #540’s objective to generate types for both loaderArgs and handlerArgs per event, it may be beneficial to also expose loaderArgs in the preload branch for ergonomics (typing loaders created outside registration), even if loaders are preloaded at runtime.
• Please confirm that hard-coding the loader return to unit in handlerArgs is the intended semantics when preloading is enabled. If handler code is expected to access loader results even in preload mode, unit may be too restrictive.

Proposed addition of loaderArgs in the preload branch:

             format!(
                 r#"@genType
+type loaderArgs = Internal.genericLoaderArgs<event, loaderContext>
+@genType
 type handlerArgs = Internal.genericHandlerArgs<event, handlerContext, unit>
 @genType
 type handler = Internal.genericHandler<handlerArgs>
 @genType
 type contractRegister = Internal.genericContractRegister<Internal.genericContractRegisterArgs<event, contractRegistrations>>"#
             )

Follow-ups:

• If you want, I can add a minimal test asserting that module_code contains the new preload-specific types when preload_handlers = true (e.g., check for type handlerArgs = Internal.genericHandlerArgs<event, handlerContext, unit> and type loaderArgs = Internal.genericLoaderArgs<event, loaderContext>). Do you want me to draft that test?

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📥 Commits

Reviewing files that changed from the base of the PR and between a021fd1 and bd82cd3.

📒 Files selected for processing (1)

• codegenerator/cli/src/hbs_templating/codegen_templates.rs (1 hunks)

⏰ Context from checks skipped due to timeout of 90000ms. You can increase the timeout in your CodeRabbit configuration to a maximum of 15 minutes (900000ms). (1)

• GitHub Check: build_and_test