Add a warning for unbound constraints in the validating loader

Closes #2165

src/Composer/Package/Loader/ValidatingArrayLoader.php

@@ -14,6 +14,7 @@ namespace Composer\Package\Loader;
 
 use Composer\Package;
 use Composer\Package\BasePackage;
+use Composer\Package\LinkConstraint\VersionConstraint;
 use Composer\Package\Version\VersionParser;
 
 /**
@@ -142,6 +143,8 @@ class ValidatingArrayLoader implements LoaderInterface
             }
         }
 
+        $unboundConstraint = new VersionConstraint('=', $this->versionParser->normalize('dev-master'));
+
         foreach (array_keys(BasePackage::$supportedLinkTypes) as $linkType) {
             if ($this->validateArray($linkType) && isset($this->config[$linkType])) {
                 foreach ($this->config[$linkType] as $package => $constraint) {
@@ -153,13 +156,27 @@ class ValidatingArrayLoader implements LoaderInterface
                         unset($this->config[$linkType][$package]);
                     } elseif ('self.version' !== $constraint) {
                         try {
-                            $this->versionParser->parseConstraints($constraint);
+                            $linkConstraint = $this->versionParser->parseConstraints($constraint);
                         } catch (\Exception $e) {
                             $this->errors[] = $linkType.'.'.$package.' : invalid version constraint ('.$e->getMessage().')';
                             unset($this->config[$linkType][$package]);
+                            continue;
+                        }
+
+                        if ('conflict' === $linkType || 'require-dev' === $linkType) {
+                            continue; // conflict can be unbound, and require-dev constraints will not impact shared libraries as they are root-only
+                        }
+
+                        if ($linkConstraint->matches($unboundConstraint)) {
+                            $this->warnings[] = $linkType.'.'.$package.' : unbound version constraint detected ('.$constraint.')';
+                            unset($this->config[$linkType][$package]);
                         }
                     }
                 }
+
+                if (empty($this->config[$linkType])) {
+                    unset($this->config[$linkType]);
+                }
             }
         }
 

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

@@ -73,14 +73,17 @@ class ValidatingArrayLoaderTest extends \PHPUnit_Framework_TestCase
                     ),
                     'require' => array(
                         'a/b' => '1.*',
+                        'b/c' => '~2',
                         'example' => '>2.0-dev,<2.4-dev',
                     ),
                     'require-dev' => array(
                         'a/b' => '1.*',
+                        'b/c' => '*',
                         'example' => '>2.0-dev,<2.4-dev',
                     ),
                     'conflict' => array(
                         'a/b' => '1.*',
+                        'b/c' => '>2.7',
                         'example' => '>2.0-dev,<2.4-dev',
                     ),
                     'replace' => array(
@@ -288,6 +291,27 @@ class ValidatingArrayLoaderTest extends \PHPUnit_Framework_TestCase
                     'support.wiki : invalid value (foo:bar), must be an http/https URL',
                 )
             ),
+            array(
+                array(
+                    'name' => 'foo/bar',
+                    'require' => array(
+                        'foo/baz' => '*',
+                        'bar/baz' => '>=1.0',
+                    ),
+                    'provide' => array(
+                        'bar/foo' => 'dev-master',
+                    ),
+                    'replace' => array(
+                        'bar/hacked' => '@stable',
+                    )
+                ),
+                array(
+                    'require.foo/baz : unbound version constraint detected (*)',
+                    'require.bar/baz : unbound version constraint detected (>=1.0)',
+                    'provide.bar/foo : unbound version constraint detected (dev-master)',
+                    'replace.bar/hacked : unbound version constraint detected (@stable)',
+                )
+            ),
         );
     }
 }