Downgrade naming errors to warnings again in package links to avoid BC issues with tags on packagist

src/Composer/Package/Loader/ValidatingArrayLoader.php

@@ -258,9 +258,9 @@ class ValidatingArrayLoader implements LoaderInterface
                         continue;
                     }
                     if ($err = self::hasPackageNamingError($package, true)) {
-                        $this->errors[] = $linkType.'.'.$err;
+                        $this->warnings[] = $linkType.'.'.$err;
                     } elseif (!Preg::isMatch('{^[A-Za-z0-9_./-]+$}', $package)) {
-                        $this->warnings[] = $linkType.'.'.$package.' : invalid key, package names must be strings containing only [A-Za-z0-9_./-]';
+                        $this->errors[] = $linkType.'.'.$package.' : invalid key, package names must be strings containing only [A-Za-z0-9_./-]';
                     }
                     if (!is_string($constraint)) {
                         $this->errors[] = $linkType.'.'.$package.' : invalid value, must be a string containing a version constraint';

tests/Composer/Test/Package/Loader/ValidatingArrayLoaderTest.php

@@ -352,18 +352,6 @@ class ValidatingArrayLoaderTest extends TestCase
                     'name : Foo/Bar is invalid, it should not contain uppercase characters. We suggest using foo/bar instead.',
                 ),
             ),
-            array(
-                array(
-                    'name' => 'foo/bar',
-                    'require' => array(
-                        'Foo/Baz' => '^1.0',
-                    ),
-                ),
-                array(
-                    'require.Foo/Baz is invalid, it should not contain uppercase characters. Please use foo/baz instead.',
-                ),
-                false,
-            ),
             array(
                 array(
                     'name' => 'foo/bar',
@@ -523,6 +511,18 @@ class ValidatingArrayLoaderTest extends TestCase
                 ),
                 false,
             ),
+            array(
+                array(
+                    'name' => 'foo/bar',
+                    'require' => array(
+                        'Foo/Baz' => '^1.0',
+                    ),
+                ),
+                array(
+                    'require.Foo/Baz is invalid, it should not contain uppercase characters. Please use foo/baz instead.',
+                ),
+                false,
+            ),
         );
     }
 }