feat: support env-mapping option

.github/workflows/main.yml

@@ -65,6 +65,7 @@ jobs:
           mount-if-exists: false
           workspace-copy: true
           native-dev-drive: false
+          env-mapping: ''
 
   test-formats:
     strategy:
@@ -303,3 +304,42 @@ jobs:
           if (-not (Test-Path -Path test.txt -PathType Leaf)) {
             exit 1
           }
+
+  test-env-mapping:
+    runs-on: windows-2022
+    steps:
+      - name: Check out source code
+        uses: actions/checkout@v4
+      - name: Setup Dev Drive
+        uses: ./
+        with:
+          workspace-copy: true
+          env-mapping: |
+            CARGO_HOME,{{ DEV_DRIVE }}/.cargo
+            RUSTUP_HOME,{{ DEV_DRIVE }}/.rustup
+            MY_ENV_VAR , {{ DEV_DRIVE_PATH }}
+            MY_OTHER_ENV_VAR,{{   DEV_DRIVE_WORKSPACE   }}\other\path
+            SHOULD_WARN,
+            should_also_warn,about_template
+            invalid-env-var,???
+            invalid.env.var,!!!
+            ENV_VAR_VALUE_INCLUDES_COMMAS,{{ DEV_DRIVE}}/my file name, with commas.txt
+            a
+            ,
+            42,{{ DEV_DRIVE }}/42
+            does_it_substitute_1137,{{ DEV_DRIVE }}/$DEV_DRIVE
+      - name: Verify Env Mapping
+        run: |
+          if ($Env:CARGO_HOME -ne '${{ env.DEV_DRIVE }}/.cargo') { Write-Error 'Failed CARGO_HOME'; exit 1 }
+          if ($Env:RUSTUP_HOME -ne '${{ env.DEV_DRIVE }}/.rustup') { Write-Error 'Failed RUSTUP_HOME'; exit 1 }
+          if ($Env:MY_ENV_VAR -ne '${{ env.DEV_DRIVE_PATH }}') { Write-Error 'Failed MY_ENV_VAR'; exit 1 }
+          if ($Env:MY_OTHER_ENV_VAR -ne '${{ env.DEV_DRIVE_WORKSPACE }}\other\path') { Write-Error 'Failed MY_OTHER_ENV_VAR'; exit 1 }
+          if ($Env:SHOULD_WARN -ne $null) { Write-Error 'Failed SHOULD_WARN'; exit 1 }
+          if ($Env:should_also_warn -ne $null) { Write-Error 'Failed should_also_warn'; exit 1 }
+          if (${Env:invalid-env-var} -ne $null) { Write-Error 'Failed invalid-env-var'; exit 1 }
+          if (${Env:invalid.env.var} -ne $null) { Write-Error 'Failed invalid.env.var'; exit 1 }
+          if ($Env:ENV_VAR_VALUE_INCLUDES_COMMAS -ne '${{ env.DEV_DRIVE }}/my file name, with commas.txt') { Write-Error 'Failed ENV_VAR_VALUE_INCLUDES_COMMAS'; exit 1 }
+          if ($Env:a -ne $null) { Write-Error 'Failed a'; exit 1 }
+          if (${Env:,} -ne $null) { Write-Error 'Failed ,'; exit 1 }
+          if (${Env:42} -ne $null) { Write-Error 'Failed 42'; exit 1 }
+          if ($Env:does_it_substitute_1137 -ne '${{ env.DEV_DRIVE }}/$DEV_DRIVE') { Write-Error 'Failed does_it_substitute_1137'; exit 1 }

.prettierrc.json

@@ -2,7 +2,6 @@
   "arrowParens": "avoid",
   "bracketSameLine": false,
   "bracketSpacing": true,
-  "editorconfig": true,
   "endOfLine": "lf",
   "htmlWhitespaceSensitivity": "css",
   "jsxSingleQuote": false,

README.md

@@ -55,6 +55,9 @@ You can optionally pass parameters to the action as follows:
     workspace-copy: false
     # Use native dev drive support when available. Defaults to true.
     native-dev-drive: true
+    # Custom mappings of output environment variables. Defaults to no mapping.
+    env-mapping: |
+      MY_PROJECT_BIN,{{ DEV_DRIVE }}/path/to/bin
 ```
 
 This action is [compatible](#runner-compatibility) with `windows-2022` runners or above.
@@ -158,6 +161,59 @@ This action will automatically use the built-in [Windows Dev Drive](https://lear
 on your behalf when it's available on your Windows runner and `ReFS` is used.
 You can use this option to turn this automatic usage off.
 
+
+### *env-mapping*
+
+By default, this option is not set.
+
+This option provides syntactic sugar to manage the environment variables exposed by this action.
+
+On a particular job, it can be repetitive having to re-declare the environment variables like below.
+
+```yaml
+- uses: samypr100/setup-dev-drive@v3
+- name: Step A
+  env:
+    CARGO_HOME: ${{ env.DEV_DRIVE }}/.cargo
+    RUSTUP_HOME: ${{ env.DEV_DRIVE }}/.rustup
+  run: ...
+- name: Step B
+  env:
+    CARGO_HOME: ${{ env.DEV_DRIVE }}/.cargo
+    RUSTUP_HOME: ${{ env.DEV_DRIVE }}/.rustup
+  run: ...
+- name: Step C
+  env:
+    CARGO_HOME: ${{ env.DEV_DRIVE }}/.cargo
+    RUSTUP_HOME: ${{ env.DEV_DRIVE }}/.rustup
+  run: ...
+# ...
+```
+
+This option allows you to define them once per job as shown in the example below.
+
+It leverages [handlebars](https://handlebarsjs.com/) syntax under the hood to expose the supported
+[environment variables](#environment-variables), giving you the ability to create new ones with
+their contents after the action runs, so they can be automatically set in subsequent steps.
+
+**Warning**: No canonicalization is performed on the input. The template is substituted as-is with the
+typical values of the environment variables and the rest of the input is then appended as-is.
+
+```yaml
+- uses: samypr100/setup-dev-drive@v3
+  with:
+    env-mapping: |
+      CARGO_HOME,{{ DEV_DRIVE }}/.cargo
+      RUSTUP_HOME,{{ DEV_DRIVE }}/.rustup
+- name: Step A
+  run: ...
+- name: Step B
+  run: ...
+- name: Step C
+  run: ...
+# ...
+```
+
 ## Environment Variables
 
 These environment variables are meant to be used along `working-directory` to make sure

action.yml

@@ -29,6 +29,9 @@ inputs:
   native-dev-drive:
     description: "Use native dev drive support when available."
     default: "true"
+  env-mapping:
+    description: "Allows mapping environment variables generated by this action to new user-defined ones."
+    required: false
 runs:
   using: "node20"
   main: "dist/setup/index.js"