Building locally

Requirements

• Rust stable (edition 2024)
• On Windows, the Visual Studio Build Tools C++ workload — libmpv-sys needs the MSVC toolchain at link time
• PowerShell 7 (the scripts invoke pwsh)
• 7-Zip, to expand the pinned runtime archive on Windows

Run the tests

With default features playback uses a dry-run seam, so libmpv is not required:

cargo test --workspace
cargo fmt --check

That is the premise of the whole test strategy: there is no libmpv code in crates/yoyo-core, so the domain logic is fully testable anywhere.

Run with real playback

Stage the playback core first:

pwsh -NoProfile -File scripts/fetch-runtime.ps1 -Platform windows-x64

then:

pwsh -NoProfile -File scripts/dev-run.ps1
pwsh -NoProfile -File scripts/dev-run.ps1 D:\videos\a.mp4 D:\videos\b.mp4

Use dev-run.ps1, not a bare cargo run

mpv-runtime cannot be a default feature — that would break cargo test on machines without libmpv. dev-run.ps1 uses its own --target-dir, because a plain cargo test / cargo build rebuilds the same binary without mpv-runtime and silently replaces it. The next launch then reports "Playback runtime is disabled in this build", which looks exactly like a regression.

Package

pwsh -NoProfile -File scripts/fetch-runtime.ps1 -Platform windows-x64
pwsh -NoProfile -File scripts/package.ps1 -Platform windows-x64 -Configuration release -RequireRuntime

Artifacts land in dist/YoYoVideo-windows-x64/ and dist/YoYoVideo-windows-x64.zip.

Verification and smoke test:

pwsh -NoProfile -File scripts/verify-package.ps1 -Platform windows-x64 -RequireRuntime
pwsh -NoProfile -File scripts/smoke-package.ps1 -Platform windows-x64 -RequireRuntime

smoke-package.ps1 generates a WAV, actually decodes it with the packaged playback core, and waits for duration, position and track events — an artifact that cannot decode never reaches the release page.

Optional NSIS installer:

pwsh -NoProfile -File scripts/build-installer.ps1 -PackageDir dist/YoYoVideo-windows-x64 -OutputPath dist/YoYoVideo-windows-x64-setup.exe

Updating the playback core

The core's version and checksum live in runtime/manifest.toml. To upgrade, change source_url, sha256 and version, then re-run fetch, package and smoke. version is part of the cache filename, so changing it forces a fresh download instead of silently reusing the old archive.

Icons

The app icon is generated, not a hand-exported bitmap:

node scripts/generate-icons.mjs

It renders the same geometry (a rounded square with a play triangle, shared with docs-site/docs/public/logo.svg) into a Windows .ico with seven sizes, the PNGs the Linux package installs, and the PNG the Slint window uses. The outputs are committed; re-run the script after changing the shape. It needs no image tooling -- the PNG and ICO encoding is in the script.