Improve error reporting for exts overridden by platform config, fixes #9876

src/Composer/DependencyResolver/Problem.php

@@ -181,26 +181,16 @@ class Problem
     {
         // handle php/hhvm
         if ($packageName === 'php' || $packageName === 'php-64bit' || $packageName === 'hhvm') {
-            $version = phpversion();
-            $available = $pool->whatProvides($packageName);
-
-            if (count($available)) {
-                $firstAvailable = reset($available);
-                $version = $firstAvailable->getPrettyVersion();
-                $extra = $firstAvailable->getExtra();
-                if ($firstAvailable instanceof CompletePackageInterface && isset($extra['config.platform']) && $extra['config.platform'] === true) {
-                    $version .= '; ' . str_replace('Package ', '', $firstAvailable->getDescription());
-                }
-            }
+            $version = self::getPlatformPackageVersion($pool, $packageName, phpversion());
 
             $msg = "- Root composer.json requires ".$packageName.self::constraintToText($constraint).' but ';
 
-            if (defined('HHVM_VERSION') || (count($available) && $packageName === 'hhvm')) {
+            if (defined('HHVM_VERSION') || ($packageName === 'hhvm' && count($pool->whatProvides($packageName)) > 0)) {
                 return array($msg, 'your HHVM version does not satisfy that requirement.');
             }
 
             if ($packageName === 'hhvm') {
-                return array($msg, 'you are running this with PHP and not HHVM.');
+                return array($msg, 'HHVM was not detected on this machine, make sure it is in your PATH.');
             }
 
             return array($msg, 'your '.$packageName.' version ('. $version .') does not satisfy that requirement.');
@@ -213,7 +203,9 @@ class Problem
             }
 
             $ext = substr($packageName, 4);
-            $error = extension_loaded($ext) ? 'it has the wrong version ('.(phpversion($ext) ?: '0').') installed' : 'it is missing from your system';
+            $version = self::getPlatformPackageVersion($pool, $packageName, phpversion($ext) ?: '0');
+
+            $error = extension_loaded($ext) ? 'it has the wrong version ('.$version.') installed' : 'it is missing from your system';
 
             return array("- Root composer.json requires PHP extension ".$packageName.self::constraintToText($constraint).' but ', $error.'. Install or enable PHP\'s '.$ext.' extension.');
         }
@@ -358,6 +350,22 @@ class Problem
         return implode(', ', $prepared);
     }
 
+    private static function getPlatformPackageVersion(Pool $pool, $packageName, $version)
+    {
+        $available = $pool->whatProvides($packageName);
+
+        if (count($available)) {
+            $firstAvailable = reset($available);
+            $version = $firstAvailable->getPrettyVersion();
+            $extra = $firstAvailable->getExtra();
+            if ($firstAvailable instanceof CompletePackageInterface && isset($extra['config.platform']) && $extra['config.platform'] === true) {
+                $version .= '; ' . str_replace('Package ', '', $firstAvailable->getDescription());
+            }
+        }
+
+        return $version;
+    }
+
     /**
      * @param  string[]     $versions an array of pretty versions, with normalized versions as keys
      * @return list<string> a list of pretty versions and '...' where versions were removed

tests/Composer/Test/Fixtures/installer/platform-ext-solver-problems.test

@@ -0,0 +1,56 @@
+--TEST--
+Test the error output of solver problems with ext/platform packages which have platform config
+--COMPOSER--
+{
+    "repositories": [
+        {
+            "type": "package",
+            "package": [
+                {"name": "a/a", "version": "1.0.0", "require": {"ext-filter": "2.0.0"}}
+            ]
+        }
+    ],
+    "require": {
+        "a/a": "*"
+    },
+    "config": {
+        "platform": {
+            "ext-filter": "7.4.0"
+        }
+    }
+}
+
+--LOCK--
+{
+    "packages": [
+    ],
+    "packages-dev": [],
+    "aliases": [],
+    "minimum-stability": "dev",
+    "stability-flags": [],
+    "prefer-stable": false,
+    "prefer-lowest": false,
+    "platform": [],
+    "platform-dev": []
+}
+
+--RUN--
+update
+
+--EXPECT-EXIT-CODE--
+2
+
+--EXPECT-OUTPUT--
+Loading composer repositories with package information
+Updating dependencies
+Your requirements could not be resolved to an installable set of packages.
+
+  Problem 1
+    - Root composer.json requires a/a * -> satisfiable by a/a[1.0.0].
+    - a/a 1.0.0 requires ext-filter 2.0.0 -> it has the wrong version (7.4.0; overridden via config.platform, actual: %s) installed. Install or enable PHP's filter extension.
+
+To enable extensions, verify that they are enabled in your .ini files:
+__inilist__
+You can also run `php --ini` inside terminal to see which files are used by PHP in CLI mode.
+
+--EXPECT--