diff --git a/features/steps.feature b/features/steps.feature
index 7ee03d39..a1575f40 100644
--- a/features/steps.feature
+++ b/features/steps.feature
@@ -74,6 +74,9 @@ Feature: Make sure "Given", "When", "Then" steps work as expected
     Then STDOUT should match /^WP_CLI_PHP_ARGS=-dopen_basedir=.* ?wp cli info/
     And STDERR should be empty
 
+    When I run `echo {INVOKE_WP_CLI_WITH_PHP_ARGS--dopen_basedir={RUN_DIR}} eval 'echo "{RUN_DIR}";'`
+    Then STDOUT should match /^WP_CLI_PHP_ARGS=-dopen_basedir=(.*)(.*) ?wp eval echo "\1";/
+
   @require-mysql-or-mariadb
   Scenario: SQL related variables
     When I run `echo {MYSQL_BINARY}`
diff --git a/src/Context/FeatureContext.php b/src/Context/FeatureContext.php
index 65d29c38..3c9dbb0e 100644
--- a/src/Context/FeatureContext.php
+++ b/src/Context/FeatureContext.php
@@ -762,7 +762,7 @@ private static function terminate_proc( $master_pid ): void {
 
 		$output = shell_exec( "ps -o ppid,pid,command | grep $master_pid" );
 
-		foreach ( explode( PHP_EOL, $output ) as $line ) {
+		foreach ( explode( PHP_EOL, $output ? $output : '' ) as $line ) {
 			if ( preg_match( '/^\s*(\d+)\s+(\d+)/', $line, $matches ) ) {
 				$parent = $matches[1];
 				$child  = $matches[2];
@@ -939,10 +939,10 @@ protected static function bootstrap_feature_context(): void {
 	 * @return string
 	 */
 	public function replace_variables( $str ) {
+		$str = preg_replace_callback( '/\{([A-Z_][A-Z_0-9]*)\}/', [ $this, 'replace_var' ], $str );
 		if ( false !== strpos( $str, '{INVOKE_WP_CLI_WITH_PHP_ARGS-' ) ) {
 			$str = $this->replace_invoke_wp_cli_with_php_args( $str );
 		}
-		$str = preg_replace_callback( '/\{([A-Z_][A-Z_0-9]*)\}/', [ $this, 'replace_var' ], $str );
 		if ( false !== strpos( $str, '{WP_VERSION-' ) ) {
 			$str = $this->replace_wp_versions( $str );
 		}