Add activate-environment option

.github/workflows/build.yml

@@ -45,7 +45,7 @@ jobs:
         run: |
           set -euo pipefail
           latest_version="$(jq -r '.version' package.json)"
-          count_expected=13
+          count_expected=15
           count_actual="$(grep -c "setup-pixi@v$latest_version" README.md || true)"
           if [ "$count_actual" -ne "$count_expected" ]; then
             echo "::error file=README.md::Expected $count_expected mentions of \`setup-pixi@v$latest_version\` in README.md, but found $count_actual."

.github/workflows/test.yml

@@ -693,7 +693,7 @@ jobs:
           cache-write: false
           cache-key: test-cache-${{ github.sha }}-${{ github.run_attempt }}-
       # check the action logs to see if the cache write was skipped
-  
+
   pyproject:
     timeout-minutes: 10
     runs-on: ubuntu-latest
@@ -717,6 +717,113 @@ jobs:
           cache: true
           manifest-path: test/pyproject-manifest/pyproject.toml
 
+  environment-activation-unix:
+    strategy:
+      matrix:
+        os: [ubuntu-latest, macos-latest]
+    runs-on: ${{ matrix.os }}
+    steps:
+      - uses: actions/checkout@v4
+      - name: Move pixi.toml
+        run: mv test/default/* .
+      - uses: ./
+        with:
+          activate-environment: true
+      - run: which python | grep '.pixi/envs/default/bin/python'
+      - run: env | grep CONDA_PREFIX
+      - run: '[[ $PIXI_ENVIRONMENT_NAME = "default" ]]'
+
+  environment-activation-windows-bash:
+    runs-on: windows-latest
+    defaults:
+      run:
+        shell: bash
+    steps:
+      - uses: actions/checkout@v4
+      - name: Move pixi.toml
+        run: mv test/default/* .
+      - uses: ./
+        with:
+          activate-environment: true
+      - run: which python | grep '.pixi/envs/default/python'
+      - run: env | grep CONDA_PREFIX
+      - run: '[[ $PIXI_ENVIRONMENT_NAME = "default" ]]'
+
+  environment-activation-windows-pwsh:
+    runs-on: windows-latest
+    defaults:
+      run:
+        shell: pwsh
+    steps:
+      - uses: actions/checkout@v4
+      - name: Move pixi.toml
+        run: mv test/default/* .
+      - uses: ./
+        with:
+          activate-environment: true
+      - run: if (-Not (Get-Command python).Path -like '*\.pixi\envs\default\python') { exit 1 }
+      - run: if (!$env:CONDA_PREFIX) { exit 1 }
+      - run: if ($env:PIXI_ENVIRONMENT_NAME -ne "default") { exit 1 }
+
+  environment-activation-windows-cmd:
+    runs-on: windows-latest
+    defaults:
+      run:
+        shell: cmd
+    steps:
+      - uses: actions/checkout@v4
+      - name: Move pixi.toml
+        run: mv test/default/* .
+      - uses: ./
+        with:
+          activate-environment: true
+      - run: where python | findstr "\.pixi\\envs\\default\\python.exe"
+      - run: set | findstr CONDA_PREFIX
+      - run: |
+          if defined PIXI_ENVIRONMENT_NAME (
+            if "%PIXI_ENVIRONMENT_NAME%" NEQ "default" (
+              exit 1
+            )
+          )
+
+  environment-activation-false:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - name: Move pixi.toml
+        run: mv test/default/* .
+      - uses: ./
+        with:
+          activate-environment: false
+      - run: '[[ $PIXI_ENVIRONMENT_NAME = "" ]]'
+
+  environment-activation-explicit-env:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - name: Move pixi.toml
+        run: mv test/multiple-environments/* .
+      - uses: ./
+        with:
+          environments: py311
+          activate-environment: true
+      - run: which python | grep '.pixi/envs/py311/bin/python'
+      - run: '[[ $PIXI_ENVIRONMENT_NAME = "py311" ]]'
+
+  environment-activation-multiple-env:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - name: Move pixi.toml
+        run: mv test/multiple-environments/* .
+      - uses: ./
+        with:
+          environments: >-
+            py311 py312
+          activate-environment: py311
+      - run: which python | grep '.pixi/envs/py311/bin/python'
+      - run: '[[ $PIXI_ENVIRONMENT_NAME = "py311" ]]'
+
   # not properly testable
   # https://github.com/actions/runner/issues/2347
   # https://github.com/orgs/community/discussions/15452

README.md

@@ -23,7 +23,7 @@ GitHub Action to set up the [pixi](https://github.com/prefix-dev/pixi) package m
 ## Usage
 
 ```yml
-- uses: prefix-dev/setup-pixi@v0.6.0
+- uses: prefix-dev/setup-pixi@v0.7.0
   with:
     pixi-version: v0.21.1
     cache: true
@@ -34,7 +34,7 @@ GitHub Action to set up the [pixi](https://github.com/prefix-dev/pixi) package m
 
 > [!WARNING]
 > Since pixi is not yet stable, the API of this action may change between minor versions.
-> Please pin the versions of this action to a specific version (i.e., `prefix-dev/setup-pixi@v0.6.0`) to avoid breaking changes.
+> Please pin the versions of this action to a specific version (i.e., `prefix-dev/setup-pixi@v0.7.0`) to avoid breaking changes.
 > You can automatically update the version of this action by using [Dependabot](https://docs.github.com/en/code-security/dependabot/working-with-dependabot/keeping-your-actions-up-to-date-with-dependabot).
 >
 > Put the following in your `.github/dependabot.yml` file to enable Dependabot for your GitHub Actions:
@@ -73,7 +73,7 @@ In order to not exceed the [10 GB cache size limit](https://docs.github.com/en/a
 This can be done by setting the `cache-write` argument.
 
 ```yml
-- uses: prefix-dev/setup-pixi@v0.6.0
+- uses: prefix-dev/setup-pixi@v0.7.0
   with:
     cache: true
     cache-write: ${{ github.event_name == 'push' && github.ref_name == 'main' }}
@@ -118,7 +118,7 @@ test:
       environment: [py311, py312]
   steps:
   - uses: actions/checkout@v4
-  - uses: prefix-dev/setup-pixi@v0.6.0
+  - uses: prefix-dev/setup-pixi@v0.7.0
     with:
       environments: ${{ matrix.environment }}
 ```
@@ -128,7 +128,7 @@ test:
 The following example will install both the `py311` and the `py312` environment on the runner.
 
 ```yml
-- uses: prefix-dev/setup-pixi@v0.6.0
+- uses: prefix-dev/setup-pixi@v0.7.0
   with:
     # separated by spaces
     environments: >-
@@ -163,7 +163,7 @@ Specify the token using the `auth-token` input argument.
 This form of authentication (bearer token in the request headers) is mainly used at [prefix.dev](https://prefix.dev).
 
 ```yml
-- uses: prefix-dev/setup-pixi@v0.6.0
+- uses: prefix-dev/setup-pixi@v0.7.0
   with:
     auth-host: prefix.dev
     auth-token: ${{ secrets.PREFIX_DEV_TOKEN }}
@@ -175,7 +175,7 @@ Specify the username and password using the `auth-username` and `auth-password`
 This form of authentication (HTTP Basic Auth) is used in some enterprise environments with [artifactory](https://jfrog.com/artifactory) for example.
 
 ```yml
-- uses: prefix-dev/setup-pixi@v0.6.0
+- uses: prefix-dev/setup-pixi@v0.7.0
   with:
     auth-host: custom-artifactory.com
     auth-username: ${{ secrets.PIXI_USERNAME }}
@@ -188,7 +188,7 @@ Specify the conda-token using the `conda-token` input argument.
 This form of authentication (token is encoded in URL: `https://my-quetz-instance.com/t/<token>/get/custom-channel`) is used at [anaconda.org](https://anaconda.org) or with [quetz instances](https://github.com/mamba-org/quetz).
 
 ```yml
-- uses: prefix-dev/setup-pixi@v0.6.0
+- uses: prefix-dev/setup-pixi@v0.7.0
   with:
     auth-host: anaconda.org # or my-quetz-instance.com
     conda-token: ${{ secrets.CONDA_TOKEN }}
@@ -228,13 +228,39 @@ If you want to use PowerShell, you need to specify `-Command` as well.
 > There are some custom shells provided by GitHub that have slightly different behavior, see [`jobs.<job_id>.steps[*].shell`](https://docs.github.com/en/actions/using-workflows/workflow-syntax-for-github-actions#jobsjob_idstepsshell) in the documentation.
 > See the [official documentation](https://docs.github.com/en/actions/using-workflows/workflow-syntax-for-github-actions#custom-shell) and [ADR 0277](https://github.com/actions/runner/blob/main/docs/adrs/0277-run-action-shell-options.md) for more information about how the `shell:` input works in GitHub Actions.
 
+### Environment activation
+
+Instead of using a custom shell wrapper, you can also make all pixi-installed binaries available to subsequent steps by "activating" the installed environment in the currently running job.
+To this end, `setup-pixi` adds all environment variables set when executing `pixi run` to `$GITHUB_ENV` and, similarly, adds all path modifications to `$GITHUB_PATH`.
+As a result, all installed binaries can be accessed without having to call `pixi run`.
+
+```yml
+- uses: prefix-dev/[email protected]
+  with:
+    activate-environment: true
+```
+
+If you are installing multiple environments, you will need to specify the name of the environment that you want to be activated.
+
+```yml
+- uses: prefix-dev/[email protected]
+  with:
+    environments: >-
+      py311
+      py312
+    activate-environment: py311
+```
+
+Activating an environment may be more useful than using a custom shell wrapper as it allows non-shell based steps to access binaries on the path.
+However, be aware that this option augments the environment of your job.
+
 ### `--frozen` and `--locked`
 
 You can specify whether `setup-pixi` should run `pixi install --frozen` or `pixi install --locked` depending on the `frozen` or the `locked` input argument.
 See the [official documentation](https://prefix.dev/docs/pixi/cli#install) for more information about the `--frozen` and `--locked` flags.
 
 ```yml
-- uses: prefix-dev/setup-pixi@v0.6.0
+- uses: prefix-dev/setup-pixi@v0.7.0
   with:
     locked: true
     # or
@@ -253,7 +279,7 @@ The first one is the debug logging of the action itself.
 This can be enabled by running the action with the `RUNNER_DEBUG` environment variable set to `true`.
 
 ```yml
-- uses: prefix-dev/setup-pixi@v0.6.0
+- uses: prefix-dev/setup-pixi@v0.7.0
   env:
     RUNNER_DEBUG: true
 ```
@@ -271,7 +297,7 @@ The second type is the debug logging of the pixi executable.
 This can be specified by setting the `log-level` input.
 
 ```yml
-- uses: prefix-dev/setup-pixi@v0.6.0
+- uses: prefix-dev/setup-pixi@v0.7.0
   with:
     # one of `q`, `default`, `v`, `vv`, or `vvv`.
     log-level: vvv
@@ -297,7 +323,7 @@ If nothing is specified, `post-cleanup` will default to `true`.
 On self-hosted runners, you also might want to alter the default pixi install location to a temporary location. You can use `pixi-bin-path: ${{ runner.temp }}/bin/pixi` to do this.
 
 ```yml
-- uses: prefix-dev/setup-pixi@v0.6.0
+- uses: prefix-dev/setup-pixi@v0.7.0
   with:
     post-cleanup: true
     # ${{ runner.temp }}\Scripts\pixi.exe on Windows
@@ -313,7 +339,7 @@ You can also use a preinstalled local version of pixi on the runner by not setti
 This can be overwritten by setting the `manifest-path` input argument.
 
 ```yml
-- uses: prefix-dev/setup-pixi@v0.6.0
+- uses: prefix-dev/setup-pixi@v0.7.0
   with:
     manifest-path: pyproject.toml
 ```

action.yml

@@ -21,8 +21,14 @@ inputs:
   environments:
     description: |
       A space-separated list of environments to install. If not specified, only the default environment is installed.
+  activate-environment:
+    description: |
+      If the installed environment should be "activated" for the current job, modifying `$GITHUB_ENV` and
+      `$GITHUB_PATH`. If more than one environment is specified in `environments`, this must be the name of the
+      environment. Defaults to `false`. Requires at least pixi v0.21.0.
   locked:
-    description: Whether to use `pixi install --locked`. Defaults to `true` when the lockfile is present, otherwise `false`.
+    description:
+      Whether to use `pixi install --locked`. Defaults to `true` when the lockfile is present, otherwise `false`.
   frozen:
     description: Whether to use `pixi install --frozen`. Defaults to `false`.
   cache: