Persist prefer-lowest in composer.lock

doc/03-cli.md

@@ -140,7 +140,9 @@ php composer.phar update vendor/*
 * **--lock:** Only updates the lock file hash to suppress warning about the
   lock file being out of date.
 * **--with-dependencies** Add also all dependencies of whitelisted packages to the whitelist.
-  So all packages with their dependencies are updated recursively.
+* **--prefer-stable:** Prefer stable versions of dependencies.
+* **--prefer-lowest:** Prefer lowest versions of dependencies. Useful for testing minimal
+  versions of requirements, generally used with `--prefer-stable`.
 
 ## require
 

src/Composer/Installer.php

@@ -309,7 +309,8 @@ class Installer
                     $aliases,
                     $this->package->getMinimumStability(),
                     $this->package->getStabilityFlags(),
-                    $this->package->getPreferStable()
+                    $this->preferStable || $this->package->getPreferStable(),
+                    $this->preferLowest
                 );
                 if ($updatedLock) {
                     $this->io->write('<info>Writing lock file</info>');
@@ -695,15 +696,18 @@ class Installer
 
     private function createPolicy()
     {
-        $preferLowest = false;
         $preferStable = null;
+        $preferLowest = null;
         if (!$this->update && $this->locker->isLocked()) {
             $preferStable = $this->locker->getPreferStable();
+            $preferLowest = $this->locker->getPreferLowest();
         }
-        // old lock file without prefer stable will return null
+        // old lock file without prefer stable/lowest will return null
         // so in this case we use the composer.json info
         if (null === $preferStable) {
             $preferStable = $this->preferStable || $this->package->getPreferStable();
+        }
+        if (null === $preferLowest) {
             $preferLowest = $this->preferLowest;
         }
 

src/Composer/Package/Locker.php

@@ -182,6 +182,15 @@ class Locker
         return isset($lockData['prefer-stable']) ? $lockData['prefer-stable'] : null;
     }
 
+    public function getPreferLowest()
+    {
+        $lockData = $this->getLockData();
+
+        // return null if not set to allow caller logic to choose the
+        // right behavior since old lock files have no prefer-lowest
+        return isset($lockData['prefer-lowest']) ? $lockData['prefer-lowest'] : null;
+    }
+
     public function getAliases()
     {
         $lockData = $this->getLockData();
@@ -213,10 +222,11 @@ class Locker
      * @param string $minimumStability
      * @param array  $stabilityFlags
      * @param bool   $preferStable
+     * @param bool   $preferLowest
      *
      * @return bool
      */
-    public function setLockData(array $packages, $devPackages, array $platformReqs, $platformDevReqs, array $aliases, $minimumStability, array $stabilityFlags, $preferStable)
+    public function setLockData(array $packages, $devPackages, array $platformReqs, $platformDevReqs, array $aliases, $minimumStability, array $stabilityFlags, $preferStable, $preferLowest)
     {
         $lock = array(
             '_readme' => array('This file locks the dependencies of your project to a known state',
@@ -229,6 +239,7 @@ class Locker
             'minimum-stability' => $minimumStability,
             'stability-flags' => $stabilityFlags,
             'prefer-stable' => $preferStable,
+            'prefer-lowest' => $preferLowest,
         );
 
         foreach ($aliases as $package => $versions) {

tests/Composer/Test/Fixtures/installer/install-dev-using-dist.test

@@ -48,6 +48,7 @@ install --prefer-dist
         "a/a": 20
     },
     "prefer-stable": false,
+    "prefer-lowest": false,
     "platform": [],
     "platform-dev": []
 }

tests/Composer/Test/Fixtures/installer/install-from-empty-lock.test

@@ -25,7 +25,8 @@ Requirements from the composer file are not installed if the lock file is presen
     "aliases": [],
     "minimum-stability": "stable",
     "stability-flags": [],
-    "prefer-stable": false
+    "prefer-stable": false,
+    "prefer-lowest": false
 }
 --RUN--
 install

tests/Composer/Test/Fixtures/installer/install-missing-alias-from-lock.test

@@ -33,7 +33,8 @@ Installing an old alias that doesn't exist anymore from a lock is possible
     "aliases": [],
     "minimum-stability": "dev",
     "stability-flags": [],
-    "prefer-stable": false
+    "prefer-stable": false,
+    "prefer-lowest": false
 }
 --RUN--
 install

tests/Composer/Test/Fixtures/installer/partial-update-downgrades-non-whitelisted-unstable.test

@@ -36,6 +36,7 @@ Partial update from lock file should apply lock file and downgrade unstable pack
         "b/unstable": 15
     },
     "prefer-stable": false,
+    "prefer-lowest": false,
     "platform": [],
     "platform-dev": []
 }
@@ -59,6 +60,7 @@ update c/uptodate
     "minimum-stability": "stable",
     "stability-flags": [],
     "prefer-stable": false,
+    "prefer-lowest": false,
     "platform": [],
     "platform-dev": []
 }

tests/Composer/Test/Fixtures/installer/partial-update-from-lock.test

@@ -36,6 +36,7 @@ Partial update from lock file should update everything to the state of the lock,
         "b/unstable": 15
     },
     "prefer-stable": false,
+    "prefer-lowest": false,
     "platform": [],
     "platform-dev": []
 }
@@ -59,6 +60,7 @@ update b/unstable
     "minimum-stability": "stable",
     "stability-flags": [],
     "prefer-stable": false,
+    "prefer-lowest": false,
     "platform": [],
     "platform-dev": []
 }

tests/Composer/Test/Fixtures/installer/partial-update-without-lock.test

@@ -43,6 +43,7 @@ update b/unstable
     "minimum-stability": "stable",
     "stability-flags": [],
     "prefer-stable": false,
+    "prefer-lowest": false,
     "platform": [],
     "platform-dev": []
 }

tests/Composer/Test/Fixtures/installer/update-alias-lock.test

@@ -39,7 +39,8 @@ Update aliased package does not mess up the lock file
     "aliases": [],
     "minimum-stability": "dev",
     "stability-flags": [],
-    "prefer-stable": false
+    "prefer-stable": false,
+    "prefer-lowest": false
 }
 --INSTALLED--
 [
@@ -66,6 +67,7 @@ update
     "minimum-stability": "dev",
     "stability-flags": [],
     "prefer-stable": false,
+    "prefer-lowest": false,
     "platform": [],
     "platform-dev": []
 }

tests/Composer/Test/Fixtures/installer/update-whitelist-reads-lock.test

@@ -32,7 +32,8 @@ Limited update takes rules from lock if available, and not from the installed re
     "aliases": [],
     "minimum-stability": "stable",
     "stability-flags": [],
-    "prefer-stable": false
+    "prefer-stable": false,
+    "prefer-lowest": false
 }
 --INSTALLED--
 [

tests/Composer/Test/Fixtures/installer/updating-dev-from-lock-removes-old-deps.test

@@ -20,7 +20,8 @@ Installing locked dev packages should remove old dependencies
     "aliases": [],
     "minimum-stability": "dev",
     "stability-flags": [],
-    "prefer-stable": false
+    "prefer-stable": false,
+    "prefer-lowest": false
 }
 --INSTALLED--
 [

tests/Composer/Test/Fixtures/installer/updating-dev-updates-url-and-reference.test

@@ -32,7 +32,8 @@ Updating a dev package for new reference updates the url and reference
     "aliases": [],
     "minimum-stability": "dev",
     "stability-flags": {"a/a":20},
-    "prefer-stable": false
+    "prefer-stable": false,
+    "prefer-lowest": false
 }
 --INSTALLED--
 [
@@ -59,6 +60,7 @@ update
     "minimum-stability": "dev",
     "stability-flags": {"a/a":20},
     "prefer-stable": false,
+    "prefer-lowest": false,
     "platform": [],
     "platform-dev": []
 }

tests/Composer/Test/Package/LockerTest.php

@@ -135,9 +135,10 @@ class LockerTest extends \PHPUnit_Framework_TestCase
                 'platform' => array(),
                 'platform-dev' => array(),
                 'prefer-stable' => false,
+                'prefer-lowest' => false,
             ));
 
-        $locker->setLockData(array($package1, $package2), array(), array(), array(), array(), 'dev', array(), false);
+        $locker->setLockData(array($package1, $package2), array(), array(), array(), array(), 'dev', array(), false, false);
     }
 
     public function testLockBadPackages()
@@ -156,7 +157,7 @@ class LockerTest extends \PHPUnit_Framework_TestCase
 
         $this->setExpectedException('LogicException');
 
-        $locker->setLockData(array($package1), array(), array(), array(), array(), 'dev', array(), false);
+        $locker->setLockData(array($package1), array(), array(), array(), array(), 'dev', array(), false, false);
     }
 
     public function testIsFresh()