Add --no-interaction flag to prevent Git/SSH prompts in package commands

features/package-install.feature

@@ -1262,3 +1262,20 @@ Feature: Install WP-CLI packages
       Error: ZipArchive failed to unzip 'package-dir/zero.zip': Not a zip archive (19).
       """
     And STDOUT should be empty
+
+  @github-api
+  Scenario: Install package with --no-interaction fails fast on Git authentication errors
+    Given an empty directory
+
+    # Try to install from a repository that requires authentication
+    # With --no-interaction and GIT_TERMINAL_PROMPT=0, Git will fail immediately
+    # instead of prompting for credentials
+    When I try `wp package install git@github.com:wp-cli-private-test/authentication-required.git --no-interaction`
+    Then the return code should be 1
+    # The command should fail fast without hanging
+    And STDERR should contain:
+      """
+      Package installation failed
+      """
+    # Git should report it couldn't authenticate, not prompt
+    And STDERR should match /fatal:|Could not read from remote repository|Repository not found/

features/package-update.feature

@@ -194,3 +194,22 @@ Feature: Update WP-CLI packages
       Error: Package 'non-existent/package' is not installed.
       """
     And the return code should be 1
+
+  @github-api
+  Scenario: Update packages with --no-interaction completes without prompting
+    Given an empty directory
+
+    # Install a real package
+    When I run `wp package install danielbachhuber/wp-cli-reset-post-date-command`
+    Then STDOUT should contain:
+      """
+      Success: Package installed.
+      """
+
+    # Update with --no-interaction should complete without hanging
+    When I run `wp package update --no-interaction`
+    Then STDOUT should contain:
+      """
+      Packages updated.
+      """
+    And STDERR should be empty

features/package.feature

@@ -209,6 +209,25 @@ Feature: Manage WP-CLI packages
       {NO_SUCH_PACKAGE_COMPOSER_JSON}
       """
 
+  @github-api
+  Scenario: Uninstall a package with --no-interaction prevents Git credential prompts
+    Given an empty directory
+
+    # Install a real package first
+    When I run `wp package install danielbachhuber/wp-cli-reset-post-date-command`
+    Then STDOUT should contain:
+      """
+      Success: Package installed.
+      """
+
+    # Uninstall with --no-interaction should complete without hanging
+    When I run `wp package uninstall danielbachhuber/wp-cli-reset-post-date-command --no-interaction`
+    Then STDERR should be empty
+    And STDOUT should contain:
+      """
+      Success: Uninstalled package.
+      """
+
   Scenario: List packages with --skip-update-check flag
     Given an empty directory
 

src/Package_Command.php

@@ -198,6 +198,9 @@ public function browse( $_, $assoc_args ) {
 	 * [--insecure]
 	 * : Retry downloads without certificate validation if TLS handshake fails. Note: This makes the request vulnerable to a MITM attack.
 	 *
+	 * [--interaction]
+	 * : Control interactive mode. Use `--no-interaction` to disable prompts (interactive by default). Useful for scripting.
+	 *
 	 * ## EXAMPLES
 	 *
 	 *     # Install a package hosted at a git URL.
@@ -215,7 +218,12 @@ public function browse( $_, $assoc_args ) {
 	public function install( $args, $assoc_args ) {
 		list( $package_name ) = $args;
 
-		$insecure = (bool) Utils\get_flag_value( $assoc_args, 'insecure', false );
+		$insecure    = (bool) Utils\get_flag_value( $assoc_args, 'insecure', false );
+		$interaction = (bool) Utils\get_flag_value( $assoc_args, 'interaction', true );
+
+		if ( ! $interaction ) {
+			$this->set_non_interactive_mode();
+		}
 
 		$this->set_composer_auth_env_var();
 		$git_package = false;
@@ -624,6 +632,9 @@ public function get( $args, $assoc_args ) {
 	 * [<package-name>...]
 	 * : One or more package names to update. If not specified, all packages will be updated.
 	 *
+	 * [--interaction]
+	 * : Control interactive mode. Use `--no-interaction` to disable prompts (interactive by default). Useful for scripting.
+	 *
 	 * ## EXAMPLES
 	 *
 	 *     # Update all packages.
@@ -651,8 +662,17 @@ public function get( $args, $assoc_args ) {
 	 *     Generating autoload files
 	 *     ---
 	 *     Success: Package updated successfully.
+	 *
+	 * @param array<string>             $args       Positional arguments. One or more package names to update.
+	 * @param array{interaction?: bool} $assoc_args Associative arguments.
 	 */
-	public function update( $args = [] ) {
+	public function update( $args, $assoc_args = [] ) {
+		$interaction = (bool) Utils\get_flag_value( $assoc_args, 'interaction', true );
+
+		if ( ! $interaction ) {
+			$this->set_non_interactive_mode();
+		}
+
 		$this->set_composer_auth_env_var();
 
 		// Validate package names if provided
@@ -749,6 +769,9 @@ function ( $event ) use ( &$updated_packages ) {
 	 * [--insecure]
 	 * : Retry downloads without certificate validation if TLS handshake fails. Note: This makes the request vulnerable to a MITM attack.
 	 *
+	 * [--interaction]
+	 * : Control interactive prompts. Use `--no-interaction` to disable interactive questions (useful for scripting).
+	 *
 	 * ## EXAMPLES
 	 *
 	 *     # Uninstall package.
@@ -761,7 +784,12 @@ function ( $event ) use ( &$updated_packages ) {
 	public function uninstall( $args, $assoc_args ) {
 		list( $package_name ) = $args;
 
-		$insecure = (bool) Utils\get_flag_value( $assoc_args, 'insecure', false );
+		$insecure    = (bool) Utils\get_flag_value( $assoc_args, 'insecure', false );
+		$interaction = (bool) Utils\get_flag_value( $assoc_args, 'interaction', true );
+
+		if ( ! $interaction ) {
+			$this->set_non_interactive_mode();
+		}
 
 		$this->set_composer_auth_env_var();
 		$package = $this->get_installed_package_by_name( $package_name );
@@ -1645,4 +1673,21 @@ private function get_github_default_branch( $package_name, $insecure = false ) {
 
 		return $default_branch;
 	}
+
+	/**
+	 * Sets environment variables to enable non-interactive mode.
+	 *
+	 * This prevents Git from prompting for credentials (e.g., SSH passwords),
+	 * which is useful for scripting and automation.
+	 *
+	 * Note: This uses putenv() which affects the entire PHP process, including
+	 * any Git operations spawned by Composer. This is intentional to ensure
+	 * non-interactive behavior propagates to all child processes.
+	 */
+	private function set_non_interactive_mode() {
+		// Prevent Git from prompting for credentials
+		putenv( 'GIT_TERMINAL_PROMPT=0' );
+		// Prevent SSH from prompting for passwords
+		putenv( 'GIT_SSH_COMMAND=ssh -o BatchMode=yes' );
+	}
 }