From f1d719565d7279f44cfda1c0bfed2920bbda6226 Mon Sep 17 00:00:00 2001
From: Feek <fiachra@squareup.com>
Date: Wed, 5 Aug 2020 15:52:20 -0700
Subject: [PATCH] feature: universal object crates

---
 config.xsd                                    |  7 ++++
 src/Psalm/Config.php                          | 35 +++++++++++++++++++
 .../InstancePropertyAssignmentAnalyzer.php    |  7 +++-
 .../Fetch/InstancePropertyFetchAnalyzer.php   |  3 +-
 tests/PropertyTypeTest.php                    | 26 ++++++++++++++
 5 files changed, 76 insertions(+), 2 deletions(-)

diff --git a/config.xsd b/config.xsd
index 167bd38dcb6..91f007d2b5d 100644
--- a/config.xsd
+++ b/config.xsd
@@ -21,6 +21,7 @@
             <xs:element name="issueHandlers" type="IssueHandlersType" minOccurs="0" maxOccurs="1" />
             <xs:element name="ignoreExceptions" type="ExceptionsType" minOccurs="0" maxOccurs="1" />
             <xs:element name="globals" type="GlobalsType" minOccurs="0" maxOccurs="1" />
+            <xs:element name="universalObjectCrates" type="UniversalObjectCratesType" minOccurs="0" maxOccurs="1" />
         </xs:choice>
 
         <xs:attribute name="autoloader" type="xs:string" />
@@ -127,6 +128,12 @@
         </xs:sequence>
     </xs:complexType>
 
+    <xs:complexType name="UniversalObjectCratesType">
+        <xs:sequence>
+            <xs:element name="class" maxOccurs="unbounded" type="NameAttributeType" />
+        </xs:sequence>
+    </xs:complexType>
+
     <xs:complexType name="ExceptionsType">
         <xs:sequence>
             <xs:element name="class" minOccurs="0" maxOccurs="unbounded" type="ExceptionType" />
diff --git a/src/Psalm/Config.php b/src/Psalm/Config.php
index a2cbc88a701..9a34cbb07df 100644
--- a/src/Psalm/Config.php
+++ b/src/Psalm/Config.php
@@ -80,6 +80,7 @@
 use const LIBXML_NONET;
 use function is_a;
 use const SCANDIR_SORT_NONE;
+use function array_map;
 
 /**
  * @psalm-suppress PropertyNotSetInConstructor
@@ -124,6 +125,15 @@ class Config
         'MixedReturnTypeCoercion',
     ];
 
+    /**
+     * These are special object classes that allow any and all properties to be get/set on them
+     * @var array<int, class-string>
+     */
+    protected $universal_object_crates = [
+        \stdClass::class,
+        SimpleXMLElement::class,
+    ];
+
     /**
      * @var static|null
      */
@@ -958,6 +968,15 @@ private static function fromXmlAndPaths(string $base_dir, string $file_contents,
             }
         }
 
+        if (isset($config_xml->universalObjectCrates) && isset($config_xml->universalObjectCrates->class)) {
+            /** @var \SimpleXMLElement $universal_object_crate */
+            foreach ($config_xml->universalObjectCrates->class as $universal_object_crate) {
+                /** @var class-string $classString */
+                $classString = $universal_object_crate['name'];
+                $config->addUniversalObjectCrate($classString);
+            }
+        }
+
         if (isset($config_xml->ignoreExceptions)) {
             if (isset($config_xml->ignoreExceptions->class)) {
                 /** @var \SimpleXMLElement $exception_class */
@@ -2109,4 +2128,20 @@ private function getPHPVersionFromComposerJson(): ?string
         }
         return null;
     }
+
+    /**
+     * @param class-string $class
+     */
+    public function addUniversalObjectCrate(string $class): void
+    {
+        $this->universal_object_crates[] = $class;
+    }
+
+    /**
+     * @return array<int, lowercase-string>
+     */
+    public function getUniversalObjectCrates(): array
+    {
+        return array_map('strtolower', $this->universal_object_crates);
+    }
 }
diff --git a/src/Psalm/Internal/Analyzer/Statements/Expression/Assignment/InstancePropertyAssignmentAnalyzer.php b/src/Psalm/Internal/Analyzer/Statements/Expression/Assignment/InstancePropertyAssignmentAnalyzer.php
index 971466fcec0..afc98392a01 100644
--- a/src/Psalm/Internal/Analyzer/Statements/Expression/Assignment/InstancePropertyAssignmentAnalyzer.php
+++ b/src/Psalm/Internal/Analyzer/Statements/Expression/Assignment/InstancePropertyAssignmentAnalyzer.php
@@ -4,6 +4,7 @@
 use PhpParser;
 use PhpParser\Node\Expr\PropertyFetch;
 use PhpParser\Node\Stmt\PropertyProperty;
+use Psalm\Config;
 use Psalm\Internal\Analyzer\ClassAnalyzer;
 use Psalm\Internal\Analyzer\ClassLikeAnalyzer;
 use Psalm\Internal\Analyzer\NamespaceAnalyzer;
@@ -268,7 +269,11 @@ public static function analyze(
                     (
                         in_array(
                             strtolower($lhs_type_part->value),
-                            ['stdclass', 'simplexmlelement', 'dateinterval', 'domdocument', 'domnode'],
+                            Config::getInstance()->getUniversalObjectCrates() + [
+                                'dateinterval',
+                                'domdocument',
+                                'domnode'
+                            ],
                             true
                         )
                     )
diff --git a/src/Psalm/Internal/Analyzer/Statements/Expression/Fetch/InstancePropertyFetchAnalyzer.php b/src/Psalm/Internal/Analyzer/Statements/Expression/Fetch/InstancePropertyFetchAnalyzer.php
index ba5021908ee..a752092b223 100644
--- a/src/Psalm/Internal/Analyzer/Statements/Expression/Fetch/InstancePropertyFetchAnalyzer.php
+++ b/src/Psalm/Internal/Analyzer/Statements/Expression/Fetch/InstancePropertyFetchAnalyzer.php
@@ -2,6 +2,7 @@
 namespace Psalm\Internal\Analyzer\Statements\Expression\Fetch;
 
 use PhpParser;
+use Psalm\Config;
 use Psalm\Internal\Analyzer\ClassLikeAnalyzer;
 use Psalm\Internal\Analyzer\FunctionLikeAnalyzer;
 use Psalm\Internal\Analyzer\NamespaceAnalyzer;
@@ -397,7 +398,7 @@ public static function analyze(
             // but we don't want to throw an error
             // Hack has a similar issue: https://github.com/facebook/hhvm/issues/5164
             if ($lhs_type_part instanceof TObject
-                || in_array(strtolower($lhs_type_part->value), ['stdclass', 'simplexmlelement'], true)
+                || in_array(strtolower($lhs_type_part->value), Config::getInstance()->getUniversalObjectCrates(), true)
             ) {
                 $statements_analyzer->node_data->setType($stmt, Type::getMixed());
 
diff --git a/tests/PropertyTypeTest.php b/tests/PropertyTypeTest.php
index 4b457e13127..94d2203bfac 100644
--- a/tests/PropertyTypeTest.php
+++ b/tests/PropertyTypeTest.php
@@ -127,6 +127,32 @@ public function getX(bool $b): int {
         $this->analyzeFile('somefile.php', new Context());
     }
 
+    /**
+     * @return void
+     */
+    public function testUniversalObjectCrates(): void
+    {
+        /** @var class-string $classString */
+        $classString = 'Foo';
+        Config::getInstance()->addUniversalObjectCrate($classString);
+
+        $this->addFile(
+            'somefile.php',
+            '<?php
+                class Foo { }
+
+                $f = new Foo();
+                // reads are fine
+                $f->bar;
+
+                // sets are fine
+                $f->buzz = false;
+        '
+        );
+
+        $this->analyzeFile('somefile.php', new Context());
+    }
+
     /**
      * @return void
      */