fix(cmake): key the GUI merge on the GUI target, not on TouchGFX

[tobymurray]

Rationale: moving forward with CustomGUI, which is not represented in this repo presently

una_app_build_app() lists what the merge step must wait for, and adds the GUI ELF only when TOUCHGFX_PATH is defined. That asks whether the app uses TouchGFX. What it needs to know is whether una_app_build_gui() built a GUI ELF.

The two matched while TouchGFX was the only way to draw one. Since cb1ae1f the SDK also ships the CustomGUI entry point, which needs only a Gui class taking the kernel and a run(), and leaves the app to own the message loop. An app using it builds a GUI ELF and sets no TOUCHGFX_PATH, so the merge target never depends on that ELF: the generated makefile lists Service.elf alone.

The ELF is still built, because add_executable puts it in all. What is missing is the ordering, so app_merging.py races the post-build step that packs Tmp/*.gui. "make App" fails outright with "Missing .gui file", which is required for every type but Glance, and a full parallel make succeeds or fails depending on scheduling order. Both outcomes were observed on one tree.

Glances are why that file is optional, and they are unaffected: a glance app has no GUI ELF by design. Its service asks the kernel for the glance geometry, sends a list of SDK::Glance controls with RequestGlanceUpdate, and the kernel draws them, so there is no app framebuffer and no GUI process to wait for.

if(TARGET) asks CMake the question directly. TOUCHGFX_PATH stays in the condition for apps that call una_app_build_app() before una_app_build_gui(), where the target does not exist yet and add_custom_target resolves DEPENDS at generate time.

Summary by CodeRabbit

• Bug Fixes
  • Improved CustomGUI build support by ensuring the final application correctly includes the GUI component when available.
  • Preserved existing behavior for configurations set before the target is created.

[coderabbitai]

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ℹ️ Recent review info

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📥 Commits

Reviewing files that changed from the base of the PR and between edf2fee and b5dd200.

📒 Files selected for processing (1)

• cmake/una-app.cmake

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📝 Walkthrough

Walkthrough

Final app merging now detects an existing GUI ELF target or a defined TOUCHGFX_PATH before adding the GUI dependency. This supports CustomGUI builds while preserving pre-target configuration behavior.

Changes

GUI dependency handling

Layer / File(s)	Summary
App merge dependency detection cmake/una-app.cmake	The merge logic adds the GUI ELF dependency when ${APP_NAME}GUI.elf already exists or TOUCHGFX_PATH is defined.

Estimated code review effort: 2 (Simple) | ~10 minutes

Mergeability Score: ⚪ Minimal · up to b5dd2

This change corrects GUI build ordering for CustomGUI applications without introducing an actionable merge-blocking risk; it is merge-ready after normal checks and review.

Suggested reviewers: rryles, noamsto

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly identifies the CMake fix that makes GUI merging depend on the GUI target instead of only on TouchGFX.

✨ Finishing Touches

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