Fix child-theme scaffold error when --path contains relative segments (#384)

Co-authored-by: swissspidy <841956+swissspidy@users.noreply.github.com>
Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: Pascal Birchler <pascalb@google.com>

Author: 3 people

features/scaffold.feature

@@ -116,6 +116,16 @@ Feature: WordPress code scaffolding
       """
     And the return code should be 1
 
+  @theme
+  Scenario: Scaffold a child theme with a relative --path argument containing '..'
+    Given a WP install in 'subdir'
+    And I run `wp --path=.. theme path` from 'subdir/wp-content'
+    And save STDOUT as {THEME_DIR}
+
+    When I run `wp scaffold child-theme zombieland --parent_theme=umbrella --path=..` from 'subdir/wp-content'
+    Then the {THEME_DIR}/zombieland/style.css file should exist
+    And the {THEME_DIR}/zombieland/functions.php file should exist
+
   @theme
   Scenario: Scaffold a child theme with dots in the slug
     Given a WP install

src/Scaffold_Command.php

@@ -986,12 +986,14 @@ static function ( $item ) use ( $slug ) {
 	private function check_target_directory( $type, $target_dir ) {
 		$parent_dir = dirname( self::canonicalize_path( str_replace( '\\', '/', $target_dir ) ) );
 
-		if ( 'theme' === $type && str_replace( '\\', '/', WP_CONTENT_DIR . '/themes' ) !== $parent_dir ) {
-			return sprintf( 'The target directory \'%1$s\' is not in \'%2$s\'.', $target_dir, WP_CONTENT_DIR . '/themes' );
+		$themes_dir = self::canonicalize_path( str_replace( '\\', '/', WP_CONTENT_DIR . '/themes' ) );
+		if ( 'theme' === $type && $themes_dir !== $parent_dir ) {
+			return sprintf( 'The target directory \'%1$s\' is not in \'%2$s\'.', $target_dir, $themes_dir );
 		}
 
-		if ( 'plugin' === $type && str_replace( '\\', '/', WP_PLUGIN_DIR ) !== $parent_dir ) {
-			return sprintf( 'The target directory \'%1$s\' is not in \'%2$s\'.', $target_dir, WP_PLUGIN_DIR );
+		$plugins_dir = self::canonicalize_path( str_replace( '\\', '/', WP_PLUGIN_DIR ) );
+		if ( 'plugin' === $type && $plugins_dir !== $parent_dir ) {
+			return sprintf( 'The target directory \'%1$s\' is not in \'%2$s\'.', $target_dir, $plugins_dir );
 		}
 
 		// Success.