7.1 KiB
cursor-lang
The WPF application displays the keyboard layout at the cursor.
Cloning
Binary assets — the exe icon and the MSIX logos — are stored in Git LFS, so git-lfs has to be installed before cloning:
git lfs install
git clone git@git.alrakis.kz:alrakis/cursor-lang.git
Cloning without it succeeds but leaves text pointer files in place of the
images, and the build then fails on an unreadable icon. An existing clone is
repaired with git lfs install followed by git lfs pull.
Administrator rights
The app runs as the ordinary user. Elevation was dropped so that the app can be published in the Microsoft Store: MSIX packages always run in the context of the signed-in user, and Store policy rejects apps that need administrator rights for any part of their functionality.
The cost is the optional Caps Lock hotkey. While a window of a higher integrity level holds the focus — Task Manager, Registry Editor, UAC prompts — Windows neither delivers keystrokes to the low-level hook nor accepts the layout change request, so the hotkey does nothing there. Reading the layout of a foreign window is not restricted, so the tooltip itself keeps working everywhere.
Startup
Startup is switched on from the app's settings by whichever means the build has.
A package declares it in the manifest as a windows.startupTask. A build unpacked
into a folder registers itself the way desktop programs always have — under
HKCU\Software\Microsoft\Windows\CurrentVersion\Run, which needs no administrator
rights.
Either way Windows lists the app in Settings — Apps — Startup; if the user turns
it off there, the app can no longer turn it back on and says so instead of
silently failing. The registry entry stays where it is in that case: Windows keeps
the user's verdict apart from it, under StartupApproved, and the app obeys it.
Settings
Where settings.json lives depends on how the app was installed. A separate
install keeps it in %APPDATA%\CursorLang. The packaged build keeps it in the
package's own data folder, which Windows removes together with the app — Store
apps are expected to leave nothing behind.
On its first run the packaged build picks up the settings left by a separate install and copies them over. The original file stays where it is: both builds may be installed side by side, and the app has no business deleting settings it does not own.
Updates
The app looks for new versions among the releases of its own repository. A
release counts when its tag is a plain version — v1.2.3 or 1.2.3 — and an
MSIX package is attached to it. A tag with anything else in it, v1.2.3-beta
among them, is passed over: a pre-release version is asked for on purpose, not
offered by the app.
Out of the attached files the .msixbundle is preferred — it carries both
architectures. Failing that, the package whose name holds the architecture of
this machine is taken: CursorLang-1.2.3.0-x64.msix. Those are the names
build-msix.ps1 produces, so a release is made by attaching what it built.
The package is downloaded to the temp folder and handed to the Windows app installer: it shows the publisher, asks for a confirmation and replaces the installed version. Windows checks the signature, so the package attached to a release has to be signed — an unsigned one installs nowhere but a machine in developer mode. The running app keeps working off the old files until it is restarted.
An app installed from the Store has no updates section at all: the Store updates it, and a package from the side is something Windows would not accept over it anyway.
By itself the app asks about releases once a day, at startup, and remembers the date of the last successful check in the settings. The check can be turned off there, which leaves the button in the settings window doing the same on demand.
Where the releases are looked for is set in UpdateOptions — the repository
belongs to whoever publishes the app, not to the user, so the values live in the
build rather than in settings.json:
services.AddSingleton(new UpdateOptions
{
ServiceUri = new Uri("https://git.alrakis.kz/"), // the Gitea server itself
Project = "alrakis/cursor-lang",
});
The releases come from Gitea, and its API sits on the server itself: the address
is the one the repository is opened at in a browser, and the app asks
/api/v1/repos/{owner}/{repo}/releases under it.
A closed repository needs a token. It is read from the CURSORLANG_UPDATE_TOKEN
environment variable rather than kept in the source: a secret built into the app
is a secret handed to everyone who got the app.
Tests
dotnet test
The suite lives in CursorLang.Tests and runs on xUnit. Half of the app —
windows, dispatcher timers, the keyboard hook — only works on an STA thread with
a message loop, so the tests keep one such thread for the whole run and drive
everything through it.
A few checks need a real foreground window: the caret position and the layout switch request are only observable there. Windows does not always grant the right to bring a window forward, and those checks report themselves as skipped rather than as failures — there is nothing to verify without a foreground window. The end-to-end checks start the built application as a separate process and skip themselves if the app is already running: interfering with someone else's running instance is not their business.
Coverage is collected with:
dotnet test --collect:"XPlat Code Coverage" --settings CursorLang.Tests\coverage.runsettings
What stays uncovered is what a test process cannot reach: the code paths that
require an MSIX package identity — StartupTask and the package data folder —
and the composition root in App.xaml.cs, which is exercised end-to-end instead.
Building the MSIX package
Neither Visual Studio nor the Windows SDK is required — makeappx and
signtool come from a NuGet package. The full publishing procedure — from
opening a developer account to submitting for certification — is written up in
Packaging/PUBLISHING.RU.md (Russian only).
# One-off: draw the logos and the exe icon (already committed, rerun after edits)
powershell -File Packaging\New-Assets.ps1
# Build and sign for local testing
powershell -File Packaging\build-msix.ps1 -Architectures x64 -Sign
# Build for the Store — identity comes from Partner Center
powershell -File Packaging\build-msix.ps1 -Version 1.0.1.0 `
-IdentityName 12345Alrakis.CursorLang -Publisher "CN=ABCD1234-..."
The result is artifacts\packages\CursorLang-<version>.msixbundle covering x64
and arm64. Upload it to Partner Center unsigned — the Store signs it with its own
certificate.
The app ships with its own copy of .NET: Windows does not include .NET 10, and MSIX cannot install a runtime as a package dependency.
To try the package without installing it, register the published layout — this needs Developer Mode and no signature at all:
Add-AppxPackage -Register artifacts\layout\x64\AppxManifest.xml
Remove-AppxPackage (Get-AppxPackage -Name Alrakis.CursorLang).PackageFullName