fix!: handle errors properly

src/Command.php

@@ -278,6 +278,8 @@ final class Command implements Stringable
      * Executes the command as a child process, returning a handle to it.
      *
      * By default, stdin, stdout and stderr are inherited from the parent.
+     *
+     * @throws ChildException
      */
     public function spawn(): Child
     {
@@ -299,6 +301,8 @@ final class Command implements Stringable
      * collecting its status.
      *
      * By default, stdin, stdout and stderr are inherited from the parent.
+     *
+     * @throws ChildException
      */
     public function status(): ExitStatus
     {
@@ -311,6 +315,8 @@ final class Command implements Stringable
      *
      * By default, stdout and stderr are captured (and used to provide the
      * resulting output). Stdin is not inherited from the parent.
+     *
+     * @throws ChildException
      */
     public function output(): Output
     {
@@ -396,13 +402,6 @@ final class Command implements Stringable
             }
         }
 
-        if (!is_executable($program)) {
-            throw new CommandException(sprintf(
-                'Program "%s" is not executable',
-                $program,
-            ));
-        }
-
         // Handle environment inheritance.
         $environment = $this->environment;
         if (is_array($environment) && $this->environmentInherit) {
@@ -414,7 +413,7 @@ final class Command implements Stringable
         }
 
         try {
-            set_error_handler(CommandException::handleError(...));
+            set_error_handler(ChildException::handleError(...));
             $proc = proc_open(
                 [$program, ...$this->args],
                 $descriptorSpec,