Fix regression with non-SPDX licenses in show command, refs #3885

src/Composer/Command/ShowCommand.php

@@ -392,12 +392,16 @@ EOT
         foreach ($licenses as $licenseId) {
             $license = $spdxLicense->getLicenseByIdentifier($licenseId); // keys: 0 fullname, 1 osi, 2 url
 
+            if (!$license) {
+                $out = $licenseId;
+            } else {
                 // is license OSI approved?
                 if ($license[1] === true) {
                     $out = sprintf('%s (%s) (OSI approved) %s', $license[0], $licenseId, $license[2]);
                 } else {
                     $out = sprintf('%s (%s) %s', $license[0], $licenseId, $license[2]);
                 }
+            }
 
             $this->getIO()->write('<info>license</info>  : ' . $out);
         }

src/Composer/Util/SpdxLicense.php

@@ -49,10 +49,14 @@ class SpdxLicense
      *
      * @param string $identifier
      *
-     * @return array
+     * @return array|false
      */
     public function getLicenseByIdentifier($identifier)
     {
+        if (!isset($this->licenses[$identifier])) {
+            return false;
+        }
+
         $license = $this->licenses[$identifier];
 
         // add URL for the license text (it's not included in the json)