Fix edge-case issue with abstract class not fully implementing interface

src/Psalm/Checker/ProjectChecker.php

@@ -1457,7 +1457,13 @@ class ProjectChecker
 
         $file_checker = $this->getFileCheckerForClassLike($fq_class_name);
 
-        $appearing_method_id = (string)MethodChecker::getAppearingMethodId($this, $original_method_id);
+        $appearing_method_id = MethodChecker::getAppearingMethodId($this, $original_method_id);
+
+        if (!$appearing_method_id) {
+            // this can happen for some abstract classes implementing (but not fully) interfaces
+            return;
+        }
+
         list($appearing_fq_class_name) = explode('::', $appearing_method_id);
 
         $appearing_class_storage = $this->classlike_storage_provider->get($appearing_fq_class_name);

src/Psalm/Mutation/FileMutation.php

@@ -0,0 +1,17 @@
+<?php
+namespace Psalm\Mutation;
+
+class FileMutation
+{
+    /** @var string */
+    public $file_path;
+
+    /** @var int */
+    public $start;
+
+    /** @var int */
+    public $end;
+
+    /** @var string */
+    public $insertion_text;
+}

tests/ParamTypeAdditionTest.php

@@ -0,0 +1,70 @@
+<?php
+namespace Psalm\Tests;
+
+use Psalm\Checker\FileChecker;
+
+class ParamTypeAdditionTest extends TestCase
+{
+    /** @var \Psalm\Checker\ProjectChecker */
+    protected $project_checker;
+
+    /**
+     * @return void
+     */
+    public function setUp()
+    {
+        FileChecker::clearCache();
+
+        $this->file_provider = new Provider\FakeFileProvider();
+
+        $this->project_checker = new \Psalm\Checker\ProjectChecker(
+            $this->file_provider,
+            new Provider\FakeCacheProvider()
+        );
+
+        $this->project_checker->setConfig(new TestConfig());
+
+        $this->project_checker->collect_references = true;
+    }
+
+    /**
+     * @dataProvider providerTestJsonOutputErrors
+     *
+     * @param string $input
+     * @param string $output
+     * @param int $line_number
+     * @param string $error
+     *
+     * @return void
+     */
+    public function testParamTypeAdditions($input, $output)
+    {
+        $this->addFile('somefile.php', $input);
+
+        $file_checker = new FileChecker('somefile.php', $this->project_checker);
+        $file_checker->visitAndAnalyzeMethods();
+    }
+
+    /**
+     * @return array
+     */
+    public function providerTestParamTypeAdditions()
+    {
+        return [
+            'addSimpleReturnType' => [
+                'input' => '<?php
+                    function takesString(string $s) : void {}
+
+                    function shouldTakeString($s) : void {
+                      takesString($s);
+                    }',
+                'output' => '<?php
+                    function takesString(string $s) : void {}
+
+                    function shouldTakeString(string $s) : void {
+                      takesString($s);
+                    }',
+            ],
+        ];
+    }
+}

tests/PropertyTypeTest.php

@@ -417,6 +417,32 @@ class PropertyTypeTest extends TestCase
                         public function __construct() { }
                     }',
             ],
+            'setInAbstractMethod' => [
+                '<?php
+                    interface I {
+                        public function foo() : void;
+                    }
+
+                    abstract class A implements I {
+                        /** @var string */
+                        public $bar;
+
+                        public function __construct() {
+                            $this->foo();
+                        }
+                    }
+
+                    class B extends A {
+                        public function foo() : void
+                        {
+                            $this->bar = "hello";
+                        }
+                    }',
+                'assertions' => [],
+                'error_levels' => [
+                    'PropertyNotSetInConstructor' => Config::REPORT_INFO,
+                ],
+            ],
         ];
     }
 

tests/Traits/FileCheckerValidCodeParseTestTrait.php

@@ -18,7 +18,7 @@ trait FileCheckerValidCodeParseTestTrait
      *
      * @param string $code
      * @param array<string, string> $assertions
-     * @param array<string> $error_levels
+     * @param array<string|int, string> $error_levels
      * @param array<string, Union> $scope_vars
      *
      * @return void
@@ -36,8 +36,15 @@ trait FileCheckerValidCodeParseTestTrait
             $this->markTestSkipped('Skipped due to a bug.');
         }
 
-        foreach ($error_levels as $error_level) {
-            Config::getInstance()->setCustomErrorLevel($error_level, Config::REPORT_SUPPRESS);
+        foreach ($error_levels as $error_level_key => $error_level) {
+            if (is_integer($error_level_key)) {
+                $issue_name = $error_level;
+                $error_level = Config::REPORT_SUPPRESS;
+            } else {
+                $issue_name = $error_level_key;
+            }
+
+            Config::getInstance()->setCustomErrorLevel($issue_name, $error_level);
         }
 
         $context = new Context();