From f776f524742a7cd53d7294016cba8a60a11e53cd Mon Sep 17 00:00:00 2001
From: Jordi Boggiano <j.boggiano@seld.be>
Date: Thu, 14 Oct 2021 15:12:29 +0200
Subject: [PATCH] Hint composer require alternatives if dep resolution fails,
 fixes #10136

---
 src/Composer/Command/RequireCommand.php | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/src/Composer/Command/RequireCommand.php b/src/Composer/Command/RequireCommand.php
index 578e2a208..8f511a015 100644
--- a/src/Composer/Command/RequireCommand.php
+++ b/src/Composer/Command/RequireCommand.php
@@ -387,6 +387,14 @@ EOT
 
         $status = $install->run();
         if ($status !== 0) {
+            if ($status === Installer::ERROR_DEPENDENCY_RESOLUTION_FAILED) {
+                foreach ($this->normalizeRequirements($input->getArgument('packages')) as $req) {
+                    if (!isset($req['version'])) {
+                        $io->writeError('You can also try re-running composer require with an explicit version constraint, e.g. "composer require '.$req['name'].':*" to figure out if any version is installable, or "composer require '.$req['name'].':^2.1" if you know which you need.');
+                        break;
+                    }
+                }
+            }
             $this->revertComposerFile(false);
         }