fix(build): copy frontend build output to embed target when frontend:dir is non-default by leaanthony · Pull Request #5251 · wailsapp/wails

leaanthony · 2026-04-26T13:28:59Z

Description

When frontend:dir in wails.json is set to a non-default path (e.g., ./jsfrontend), the build system correctly builds the frontend in that directory, but the //go:embed all:frontend/dist directive in main.go still references frontend/dist. This means the built assets (only a gitkeep placeholder) are not correctly included in the compiled binary, causing it to fail to start.

Changes

Added SyncFrontendDistToEmbedTarget function called after BuildFrontend
When the actual frontend directory differs from the default frontend/, discovers embed targets via staticanalysis.GetEmbedDetails and copies the built dist files to the embed target directory
No-op when using default frontend/ directory

Testing

Added tests in v2/test/5034/frontend_dir_test.go:
- TestSyncFrontendDistToEmbedTarget: verifies files are copied correctly when frontend:dir is non-default
- TestSyncFrontendDistNoOpWhenDefault: verifies no changes when using default dir
- TestSyncFrontendDistNoOpWhenNoDistInEmbed: verifies no errors when no dist embed dirs found
- TestEmbedDiscoveryInTempDir: verifies embed discovery works in temp dirs

Limitations

This fix does NOT address the case where frontend:dir points outside the project directory (e.g., "../frontend"), as Go's //go:embed directive cannot reference paths outside the module. Users in that situation need to manually update their embed directive.

Summary by CodeRabbit

New Features
- Enhanced the build process to automatically synchronize custom frontend build output into the proper directory structure during compilation, supporting custom frontend directory configurations.
Tests
- Added comprehensive end-to-end tests for frontend build output synchronization, verifying correct directory placement, cleanup behavior, and edge cases with custom frontend directories.

…dir is non-default When the frontend directory is configured via frontend:dir in wails.json to a non-default path (e.g. ./jsfrontend), the build system correctly builds the frontend in that directory but the Go embed directive still references frontend/dist. This means the built assets are not included in the compiled binary. After BuildFrontend, if the actual frontend directory differs from the default frontend/ directory, the built dist files are copied to the embed target directory discovered via static analysis of //go:embed directives. Fixes #5034

coderabbitai · 2026-04-26T13:29:06Z

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The pull request is closed.

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📥 Commits

Reviewing files that changed from the base of the PR and between 230a627 and b5b5fe1.

📒 Files selected for processing (2)

v2/pkg/commands/build/build.go
v2/test/5034/frontend_dir_test.go

Walkthrough

Adds SyncFrontendDistToEmbedTarget and integrates it into Build: it detects embed target directories via staticanalysis, copies a custom frontend's built dist into those embed-target dist folders, and returns a deferred cleanup that removes copied files and restores .gitkeep placeholders.

Changes

Frontend Dist Synchronization

Layer / File(s)	Summary
Sync function implementation and build integration `v2/pkg/commands/build/build.go`	`SyncFrontendDistToEmbedTarget` discovers embed targets via `staticanalysis.GetEmbedDetails`, conditionally copies a custom frontend `dist` into embed-target `dist` directories, returns a cleanup that removes copies and recreates `.gitkeep`, and is invoked from `Build` with deferred cleanup.
Sync and cleanup verification tests `v2/test/5034/frontend_dir_test.go`	Tests verify embed discovery, copied file contents and `.gitkeep` removal, cleanup restoration of `.gitkeep`, and no-op behavior when using the default frontend directory or when the source `dist` is missing.

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~25 minutes

Possibly related issues

[v2] Fully built apps fail to run when frontend:dir is not default #5034: Implements the frontend dist synchronization behavior described in the issue to ensure non-default frontend:dir assets are embedded.

Possibly related PRs

wailsapp/wails#3887: Related PR that updates templates to embed all:frontend/dist, which interacts with the embed targets prepared by this sync logic.

Suggested labels

Ready For Testing

Suggested reviewers

fbbdev

Poem

🐰 I hopped through dirs both near and far,
Copied dist to embeds — a careful spar,
I cleaned up footprints, left .gitkeep to stay,
Build hums along, assets snug in play,
A tiny rabbit clap for the build today!

✨ Finishing Touches

📝 Generate docstrings

Create stacked PR
Commit on current branch

🧪 Generate unit tests (beta)

Create PR with unit tests
Commit unit tests in branch v2-bugfix/5034-frontend-dir-build

Warning

There were issues while running some tools. Please review the errors and either fix the tool's configuration or disable the tool if it's a critical failure.

🔧 golangci-lint (2.12.2)

level=error msg="[linters_context] typechecking error: pattern ./...: directory prefix . does not contain main module or its selected dependencies"

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leaanthony · 2026-05-02T02:40:09Z

🤖 PR Triage Review

✅ Accepted

This PR fixes a build issue where frontend assets aren't copied to the embed target when using a custom frontend:dir. Important fix for users with non-standard project layouts.

Changes: 234 additions, 2 files changed

Platform: All (v2-only, build system)

Next Steps: Dispatching for testing on all platforms.

Reviewed by Wails PR Reviewer Bot

leaanthony · 2026-05-02T06:51:25Z

test

leaanthony · 2026-05-02T06:51:48Z

Tested on macOS (darwin/arm64) — verdict: ✓ pass

Commit: cc3095dca1
Build: 16.6s successful
Unit tests: 4/4 passing
Visual smoke: ✓ wails build with custom frontend:dir synced assets from webapp/dist/ to frontend/dist/ (the embed target), replacing a placeholder with the full Vite build output

Unit test output

=== RUN   TestEmbedDiscoveryInTempDir      --- PASS (0.16s)
=== RUN   TestSyncFrontendDistToEmbedTarget --- PASS (0.20s)
=== RUN   TestSyncFrontendDistNoOpWhenDefault --- PASS (0.00s)
=== RUN   TestSyncFrontendDistNoOpWhenNoDistInEmbed --- PASS (0.07s)
PASS
ok  github.com/wailsapp/wails/v2/test/5034  0.451s

SyncFrontendDistToEmbedTarget now returns a cleanup func that removes the copied assets and restores a .gitkeep placeholder after the build completes, keeping the working tree clean. The cleanup runs via defer so it fires whether the build succeeds or fails.

leaanthony · 2026-05-31T12:48:07Z

Added cleanup in 5945771 — SyncFrontendDistToEmbedTarget now returns a func() that the call site defers. After the build (success or failure), it removes the copied assets and writes a fresh .gitkeep so the working tree is clean.

Behaviour:

Custom frontend:dir + non-default embed target → assets copied in, build runs, copied assets removed, .gitkeep restored
Default frontend dir → noop, no-op cleanup returned
Build fails → cleanup still runs via defer, directory is restored

New test: TestSyncFrontendDistCleanupRestoresGitkeep verifies the cleanup leaves only .gitkeep in frontend/dist.

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github-actions Bot added cli v2-only labels Apr 26, 2026

leaanthony added the reviewed ✅ label May 2, 2026

leaanthony modified the milestones: v2.5.0, v2.13.0 May 20, 2026

leaanthony mentioned this pull request May 31, 2026

fix(v2): copy frontend build output to embed target when frontend:dir is custom #5178

Closed

leaanthony marked this pull request as ready for review May 31, 2026 12:51

Copilot AI review requested due to automatic review settings May 31, 2026 12:51

Merge branch 'master' into v2-bugfix/5034-frontend-dir-build

b5b5fe1

Copilot started reviewing on behalf of leaanthony May 31, 2026 12:51 View session

leaanthony merged commit f83493c into master May 31, 2026
12 of 16 checks passed

leaanthony deleted the v2-bugfix/5034-frontend-dir-build branch May 31, 2026 12:51

Copilot AI reviewed May 31, 2026

coderabbitai Bot mentioned this pull request May 31, 2026

fix(bindings): strip debug info on Windows to avoid Go 1.25 DWARF5 PE bug #5524

Merged

5 tasks

This was referenced Jun 28, 2026

fix(build): sync frontend assets to embed dir when frontend:dir is custom #5188

Closed

V2 - Fix non-default frontend:dir in builds #5035

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fix(build): copy frontend build output to embed target when frontend:dir is non-default#5251

fix(build): copy frontend build output to embed target when frontend:dir is non-default#5251
leaanthony merged 3 commits into
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v2-bugfix/5034-frontend-dir-build

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Description

Changes

Testing

Limitations

Summary by CodeRabbit

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Walkthrough

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Possibly related issues

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leaanthony commented Apr 26, 2026 •

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