fix: Install drush without affecting git index

Author: rfay

commands/web/drush

@@ -0,0 +1,14 @@
+#!/bin/bash
+
+#ddev-generated
+## Description: Run drush CLI inside the web container, installing it if necessary
+## Usage: drush [flags] [args]
+## Example: "ddev drush uli" or "ddev drush sql-cli" or "ddev drush --version"
+## ProjectTypes: drupal7,drupal8,drupal9,drupal10,drupal,backdrop
+## ExecRaw: true
+
+if ! command -v drush >/dev/null; then
+  echo "drush is not yet installed. Installing it...'"
+  .ddev/core-dev/install_drush.sh
+fi
+drush "$@"

core-dev/install_drush.sh

@@ -0,0 +1,41 @@
+#!/bin/bash
+
+#ddev-generated
+# This script installs drush/drush without changing the git
+# status of the Drupal checkout
+
+set -eu -o pipefail
+
+if command -v drush >/dev/null; then
+  echo "drush is already installed, taking no action. You can remove it if you want to reinstall"
+  exit
+fi
+
+echo "Installing drush without affecting git status"
+
+# Make certain that we have something staged so we can create stash
+touch .makedrush.txt
+git add .makedrush.txt
+
+# Save the stash, which will include anything people were doing
+# plus the .makedrush.txt. This gets us back to "no changes"
+# in `git status`
+git stash
+
+# Install drush
+composer require drush/drush
+
+# Roll back to what we started with. Cleans up
+# composer.* and anything else that the drush install changes
+# But vendor directory is untouched since
+# it's gitignored
+git reset --hard
+
+# Restore anything that might have been staged
+# prior to the start
+git stash apply
+
+# Get rid of our dummy file
+git rm -f .makedrush.txt
+
+echo "drush/drush is installed in $(which drush)"

install.yaml

@@ -8,8 +8,10 @@ project_files:
   - core-dev/phpunit-firefox.xml
   - core-dev/phpunit-chrome.xml
   - commands/web/drupal
+  - commands/web/drush
   - commands/web/phpunit
   - commands/web/nightwatch
+  - core-dev/install_drush.sh
   - core-dev/gitignore
   - core-dev/.env
   - core-dev/src/Command/AdminLoginCommand.php