Ensure packages that exist in a higher prio repo never get loaded in lower prio repos, fixes #5076

src/Composer/DependencyResolver/PoolBuilder.php

@@ -97,9 +97,14 @@ class PoolBuilder
                 }
 
                 // TODO should we really pass the callable into here?
-                $packages = $repository->loadPackages($loadNames, $this->isPackageAcceptableCallable);
+                $result = $repository->loadPackages($loadNames, $this->isPackageAcceptableCallable);
+
+                foreach ($result['namesFound'] as $name) {
+                    // avoid loading the same package again from other repositories once it has been found
+                    unset($loadNames[$name]);
+                }
+                foreach ($result['packages'] as $package) {
 
-                foreach ($packages as $package) {
                     if (call_user_func($this->isPackageAcceptableCallable, $package->getNames(), $package->getStability())) {
                         $newLoadNames += $this->loadPackage($request, $package, $key);
                     }

src/Composer/Repository/BaseRepository.php

@@ -31,16 +31,20 @@ abstract class BaseRepository implements RepositoryInterface
         $packages = $this->getPackages();
 
         $result = array();
+        $namesFound = array();
         foreach ($packages as $package) {
-            if (
-                array_key_exists($package->getName(), $packageMap)
-                && (!$packageMap[$package->getName()] || $packageMap[$package->getName()]->matches(new Constraint('==', $package->getVersion())))
-                && call_user_func($isPackageAcceptableCallable, $package->getNames(), $package->getStability())
-            ) {
-                $result[spl_object_hash($package)] = $package;
-                if ($package instanceof AliasPackage && !isset($result[spl_object_hash($package->getAliasOf())])) {
-                    $result[spl_object_hash($package->getAliasOf())] = $package->getAliasOf();
+            if (array_key_exists($package->getName(), $packageMap)) {
+                if (
+                    (!$packageMap[$package->getName()] || $packageMap[$package->getName()]->matches(new Constraint('==', $package->getVersion())))
+                    && call_user_func($isPackageAcceptableCallable, $package->getNames(), $package->getStability())
+                ) {
+                    $result[spl_object_hash($package)] = $package;
+                    if ($package instanceof AliasPackage && !isset($result[spl_object_hash($package->getAliasOf())])) {
+                        $result[spl_object_hash($package->getAliasOf())] = $package->getAliasOf();
+                    }
                 }
+
+                $namesFound[$package->getName()] = true;
             }
         }
 
@@ -52,7 +56,7 @@ abstract class BaseRepository implements RepositoryInterface
             }
         }
 
-        return $result;
+        return array('namesFound' => array_keys($namesFound), 'packages' => $result);
     }
 
     /**

src/Composer/Repository/ComposerRepository.php

@@ -143,7 +143,7 @@ class ComposerRepository extends ArrayRepository implements ConfigurableReposito
 
             $packages = $this->loadAsyncPackages(array($name => $constraint));
 
-            return reset($packages);
+            return reset($packages['packages']);
         }
 
         if ($hasProviders) {
@@ -181,7 +181,9 @@ class ComposerRepository extends ArrayRepository implements ConfigurableReposito
                 return array();
             }
 
-            return $this->loadAsyncPackages(array($name => $constraint));
+            $result = $this->loadAsyncPackages(array($name => $constraint));
+
+            return $result['packages'];
         }
 
         if ($hasProviders) {
@@ -239,7 +241,9 @@ class ComposerRepository extends ArrayRepository implements ConfigurableReposito
                     $packageMap[$name] = new EmptyConstraint();
                 }
 
-                return array_values($this->loadAsyncPackages($packageMap));
+                $result = $this->loadAsyncPackages($packageMap);
+
+                return array_values($result['packages']);
             }
 
             if ($this->hasPartialPackages()) {
@@ -297,6 +301,7 @@ class ComposerRepository extends ArrayRepository implements ConfigurableReposito
         }
 
         $packages = array();
+        $namesFound = array();
 
         if ($hasProviders || $this->hasPartialPackages()) {
             foreach ($packageNameMap as $name => $constraint) {
@@ -313,6 +318,7 @@ class ComposerRepository extends ArrayRepository implements ConfigurableReposito
                     if ($candidate->getName() !== $name) {
                         throw new \LogicException('whatProvides should never return a package with a different name than the requested one');
                     }
+                    $namesFound[$name] = true;
                     if (!$constraint || $constraint->matches(new Constraint('==', $candidate->getVersion()))) {
                         $matches[spl_object_hash($candidate)] = $candidate;
                         if ($candidate instanceof AliasPackage && !isset($matches[spl_object_hash($candidate->getAliasOf())])) {
@@ -343,10 +349,12 @@ class ComposerRepository extends ArrayRepository implements ConfigurableReposito
                 }, ARRAY_FILTER_USE_KEY);
             }
 
-            $packages = array_merge($packages, $this->loadAsyncPackages($packageNameMap, $isPackageAcceptableCallable));
+            $result = $this->loadAsyncPackages($packageNameMap, $isPackageAcceptableCallable);
+            $packages = array_merge($packages, $result['packages']);
+            $namesFound = array_merge($namesFound, $result['namesFound']);
         }
 
-        return $packages;
+        return array('namesFound' => array_keys($namesFound), 'packages' => $packages);
     }
 
     /**
@@ -586,6 +594,7 @@ class ComposerRepository extends ArrayRepository implements ConfigurableReposito
         $this->loadRootServerFile();
 
         $packages = array();
+        $namesFound = array();
         $promises = array();
         $repo = $this;
 
@@ -619,7 +628,7 @@ class ComposerRepository extends ArrayRepository implements ConfigurableReposito
             }
 
             $promises[] = $this->asyncFetchFile($url, $cacheKey, $lastModified)
-                ->then(function ($response) use (&$packages, $contents, $realName, $constraint, $repo, $isPackageAcceptableCallable) {
+                ->then(function ($response) use (&$packages, &$namesFound, $contents, $realName, $constraint, $repo, $isPackageAcceptableCallable) {
                     if (true === $response) {
                         $response = $contents;
                     }
@@ -657,6 +666,7 @@ class ComposerRepository extends ArrayRepository implements ConfigurableReposito
                         unset($expanded, $expandedVersion, $versionData);
                     }
 
+                    $namesFound[$realName] = true;
                     $versionsToLoad = array();
                     foreach ($versions as $version) {
                         if (!isset($version['version_normalized'])) {
@@ -683,7 +693,7 @@ class ComposerRepository extends ArrayRepository implements ConfigurableReposito
 
         $this->loop->wait($promises);
 
-        return $packages;
+        return array('namesFound' => $namesFound, 'packages' => $packages);
         // RepositorySet should call loadMetadata, getMetadata when all promises resolved, then metadataComplete when done so we can GC the loaded json and whatnot then as needed
     }
 

src/Composer/Repository/RepositoryInterface.php

@@ -69,7 +69,7 @@ interface RepositoryInterface extends \Countable
      *
      * @param ConstraintInterface[] $packageNameMap package names pointing to constraints
      * @param $isPackageAcceptableCallable
-     * @return PackageInterface[]
+     * @return array [namesFound => string[], packages => PackageInterface[]]
      */
     public function loadPackages(array $packageNameMap, $isPackageAcceptableCallable);
 

tests/Composer/Test/Fixtures/installer/repositories-priorities.test

@@ -0,0 +1,42 @@
+--TEST--
+Packages found in a higher priority repository take precedence even if they are not found in the requested version
+--COMPOSER--
+{
+    "repositories": [
+        {
+            "type": "package",
+            "package": [
+                { "name": "foo/a", "version": "1.0.0" }
+            ]
+        },
+        {
+            "type": "package",
+            "package": [
+                { "name": "foo/a", "version": "2.0.0" }
+            ]
+        }
+    ],
+    "require": {
+        "foo/a": "2.*"
+    }
+}
+--RUN--
+update
+--EXPECT-OUTPUT--
+Loading composer repositories with package information
+Updating dependencies
+Your requirements could not be resolved to an installable set of packages.
+
+  Problem 1
+    - The requested package foo/a could not be found in any version, there may be a typo in the package name.
+
+Potential causes:
+ - A typo in the package name
+ - The package is not available in a stable-enough version according to your minimum-stability setting
+   see <https://getcomposer.org/doc/04-schema.md#minimum-stability> for more details.
+ - It's a private package and you forgot to add a custom repository to find it
+
+Read <https://getcomposer.org/doc/articles/troubleshooting.md> for further common problems.
+--EXPECT--
+--EXPECT-EXIT-CODE--
+2

tests/Composer/Test/Fixtures/installer/repositories-priorities2.test

@@ -0,0 +1,26 @@
+--TEST--
+Packages found in a higher priority repository take precedence
+--COMPOSER--
+{
+    "repositories": [
+        {
+            "type": "package",
+            "package": [
+                { "name": "foo/a", "version": "1.0.0" }
+            ]
+        },
+        {
+            "type": "package",
+            "package": [
+                { "name": "foo/a", "version": "1.1.0" }
+            ]
+        }
+    ],
+    "require": {
+        "foo/a": "1.*"
+    }
+}
+--RUN--
+update
+--EXPECT--
+Installing foo/a (1.0.0)