cadl/CONTRIBUTING.md

Prerequisites

• Install Node.js 14 LTS or 16 LTS
• Install Rush

npm install -g @microsoft/rush

Installing NPM dependencies

rush update

This will install all of the npm dependencies of all projects in the repo. Do this whenever you git pull or your workspace is freshly cleaned/cloned.

Note that rush update must be done before building in VS Code or using the command line.

Using command line

Rebuild the whole repo

rush rebuild

This will build all projects in the correct dependency order.

Build the whole repo incrementally

rush build

This will build all projects that have changed since the last rush build in dependency order.

Build an individual package on the command line

cd packages/<project>
rushx build

Run all tests for the whole repo

rush test

Run tests for an individual package

cd packages/<project>
rushx test

Verbose test logging

Tests sometimes log extra info using logVerboseTestOutput To see this output on the command line, set environment variable ADL_VERBOSE_TEST_OUPUT=true.

Reformat source code

rush format

PR validation enforces code formatting style rules for the repo. This command will reformat code automatically so that it passes.

You can also check if your code is formatted correctly without reformatting anything using rush check-format.

See also below for having this happen automatically in VS Code whenever you save.

Using VS Code

Recommended extensions

1. Mocha Test Explorer: Run tests from the IDE.
2. Prettier: Automatically keep code formatted correctly on save.

Opening the repo as workspace

Always open the root of the repo as the workspace. Things are setup to allow easy development across packages rather than opening one package at a time in the IDE.

• File -> Open Workspace, select root folder where the Cadl repo was cloned
• Or run code /path/to/repo/root on the command line

Building

• Terminal -> Run Build Task (Ctrl+Shift+B)

This will setup a an incremental watching build for the whole repo. From there on, your changes will be built whenever you save.

Problems will be reported in the Problems pane auotomatically and the Terminal pane will have three parallel watch tasks running:

• watch-source: tsc process that recompiles on TypeScript changes
• watch-spec: process that regenerates spec.html when spec.emu.html changes
• watch-tmlanguage: process that regenerates cadl.tmlanguage when tmlanguage.ts changes

Testing

With Mocha Test Explorer installed, click on its icon in the sidebar, then click on the play button at the top or on any individual test or test group to run just one test or just one group. You can also click on the bug icon next to an individual test to debug it.

You can see additional information logged by each test using logVerboseTestOutput by clicking on the test and looking at the output pane. Unlike the command line, no environment variable is needed.

Debugging

There are several "Run and Debug" tasks set up. Click on the Run and Debug icon on the sidebar, pick one from its down, and press F5 to debug the last one you chose.

1. VS Code Extension: This will run and debug an experimental instance of VS Code with the Cadl extension for VS Code and Cadl language serever running live with any of your changes. It will attach to both the VS Code client process and the language server process automatically.
2. Compile Scratch: Use this to debug compiling packages/cadl-samples/scratch/*.cadl. The Cadl source code in that folder is excluded from source control by design. Create Cadl files there to experiment and debug how the compiler reacts.
3. Compile Scratch (nostdlib): Same as above, but skips parsing and evaluating the Cadl standard library. Sometimes it's easier to
4. Attach to Default Port: Use this to attach to a manually run node --debug command.
5. Attach to Language Server: Use this to attach to the language server process of an already running client process. Useful if you want to debug the language server in VS Code while debugging the VS client in VS.
6. Regenerate .tmlanguage: This runs the code that produces the cadl.tmlanguage file that provides syntax highlighting of Cadl in VS and VS Code. Select this to debug its build process.

Developing the Visual Studio Extension

Prerequisites

Install Visual Studio 16.9 or later. It is not currently possible to build the VS extension without it, and of course you'll need Visual Studio to run and debug the Visual Studio extension.

Build VS extension on the command line

See the command line build steps above. If you have VS installed, the VS extension will be included in your command line full repo builds automatically.

If you do not have VS installed the command line build steps above will simply skip building the VS extension and only build the VS Code extension.

Build VS extension in VS

• Open packages/cadl-vs/Microsoft.Cadl.VisualStudio.sln in Visual Studio
• Build -> Build solution (Ctrl+Shift+B)

Unlike TypeScript in VS Code above, this is not a watching build, but it is relatively fast to run. Press Ctrl+Shift+B again to build any changes after you make them.

Debug VS extension

• Click on the play icon in the toolbar or press F5

This will run and debug an experimental instance of VS with a version of the Cadl extension for VS Code running live with any of your changes to the extension or the Cadl language server.

The VS debugger will attach only to the VS client process. Use "Attach to Lanugage Server" described above to debug the language server in VS Code.

Installing your build

rush dogfood

This will globally install the @cadl-lang/compiler package, putting your build of cadl on PATH, and install the VS Code extension if VS Code is installed.

Note the important difference between this and the steps to run and debug the VS Code extension above: the dogfood command installs the Cadl extension with your changes in regular, non-experimental instance of VS Code, meaning you will have it always, and not only when running the debug steps above. This is exactly like using cadl vscode install, only instead of downloading the latest release, it uses a build with your changes applied.

There is no automatic dogfood process for installing the VS extension non-experimentally, but if you build the cadl-vs project from the command line following the steps above, or build its Release configuration in Visual Studio, then you can install it by double-clicking on packages/cadl-vs/Microsoft.Cadl.VisualStudio.vsix that gets produced.

Pull request

Trigger Cadl Playground Try It build

For contributors of the repo the build will trigger automatically but for other's forks it will need a manual trigger from a contributor. As a contributor you can run the following command to trigger the build and create a cadl playground link for this PR.

/azp run Cadl Pull Request Try It