feat: add custom install command support

.github/workflows/example-install-command.yml

@@ -0,0 +1,15 @@
+name: example-install-command
+on: [push]
+jobs:
+  install-command:
+    runs-on: ubuntu-20.04
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+
+      - name: Custom Yarn command
+        uses: ./
+        with:
+          working-directory: examples/install-command
+          # https://classic.yarnpkg.com/en/docs/cli/install
+          install-command: yarn --frozen-lockfile --silent

README.md

@@ -25,6 +25,7 @@
 - [Start server](#start-server) before running the tests
 - [Start multiple servers](#start-multiple-servers) before running the tests
 - [Wait for server](#wait-on) to respond before running the tests
+- use [custom install command](#custom-install-command)
 - use [command prefix](#command-prefix)
 - use [own custom test command](#custom-test-command)
 - pass [custom build id](#custom-build-id) when recording to Dashboard
@@ -633,6 +634,18 @@ See [example-wait-on.yml](.github/workflows/example-wait-on.yml) workflow file.
 
 If this action times out waiting for the server to respond, please see [Debugging](#debugging) section in this README file.
 
+### Custom install command
+
+If you want to overwrite the install command
+
+```yml
+- uses: cypress-io/github-action@v2
+  with:
+    install-command: yarn --frozen-lockfile --silent
+```
+
+See [example-install-command.yml](.github/workflows/example-install-command.yml) workflow file.
+
 ### Command prefix
 
 You can prefix the default test command using the `command-prefix` option. This is useful for example when running [Percy](https://docs.percy.io/docs/cypress), which requires the test command to be wrapped with `percy exec --`.

action.yml

@@ -35,6 +35,9 @@ inputs:
   install:
     description: 'Whether or not to run install'
     required: false
+  install-command:
+    description: 'Custom install command to use'
+    required: false
   runTests:
     description: 'Whether or not to run tests'
     required: false

dist/index.js

@@ -8705,9 +8705,16 @@ const install = () => {
   // prevent lots of progress messages during install
   core.exportVariable('CI', '1')
   core.exportVariable('CYPRESS_CACHE_FOLDER', CYPRESS_CACHE_FOLDER)
+  // set NPM cache path in case the user has custom install command
+  core.exportVariable('npm_config_cache', NPM_CACHE_FOLDER)
 
   // Note: need to quote found tool to avoid Windows choking on
   // npm paths with spaces like "C:\Program Files\nodejs\npm.cmd ci"
+  const installCommand = core.getInput('install-command')
+  if (installCommand) {
+    core.debug(`using custom install command "${installCommand}"`)
+    return execCommand(installCommand, true, 'install command')
+  }
 
   if (useYarn()) {
     core.debug('installing NPM dependencies using Yarn')
@@ -8721,7 +8728,6 @@ const install = () => {
     })
   } else {
     core.debug('installing NPM dependencies')
-    core.exportVariable('npm_config_cache', NPM_CACHE_FOLDER)
 
     return io.which('npm', true).then((npmPath) => {
       core.debug(`npm at "${npmPath}"`)

examples/install-command/README.md

@@ -0,0 +1,3 @@
+# example: install-command
+
+This example runs the custom install command.

examples/install-command/cypress.json

@@ -0,0 +1,6 @@
+{
+  "fixturesFolder": false,
+  "supportFile": false,
+  "pluginsFile": false,
+  "baseUrl": "https://example.cypress.io/"
+}

examples/install-command/cypress/integration/spec.js

@@ -0,0 +1,7 @@
+/// <reference types="cypress" />
+describe('example: install-only', () => {
+  it('loads the deployed site', () => {
+    cy.visit('/')
+    cy.contains('h1', 'Kitchen Sink')
+  })
+})

examples/install-command/package.json

@@ -0,0 +1,18 @@
+{
+  "name": "example-install-command",
+  "version": "1.0.0",
+  "description": "Install dependencies using custom command",
+  "scripts": {
+    "test": "cypress run"
+  },
+  "author": "Gleb Bahmutov <[email protected]>",
+  "license": "MIT",
+  "private": true,
+  "devDependencies": {
+    "cypress": "6.1.0"
+  },
+  "dependencies": {
+    "arg": "5.0.0",
+    "debug": "4.2.0"
+  }
+}