From 460120ec45fd014aeb9b0a9f40e92fd6fdfb8c5a Mon Sep 17 00:00:00 2001
From: Matthew Brown <github@muglug.com>
Date: Sat, 10 Aug 2019 09:12:02 -0400
Subject: [PATCH] Fix #1994 - make assert-if-true work for $this properties

---
 .../Statements/Expression/AssertionFinder.php | 18 ++++
 tests/AssertTest.php                          | 92 +++++++++++++++++++
 2 files changed, 110 insertions(+)

diff --git a/src/Psalm/Internal/Analyzer/Statements/Expression/AssertionFinder.php b/src/Psalm/Internal/Analyzer/Statements/Expression/AssertionFinder.php
index ea26df7e2d2..da5693bcd0f 100644
--- a/src/Psalm/Internal/Analyzer/Statements/Expression/AssertionFinder.php
+++ b/src/Psalm/Internal/Analyzer/Statements/Expression/AssertionFinder.php
@@ -1861,6 +1861,15 @@ protected static function processCustomAssertion(
                             $if_types[$var_id] = [[$prefix . $assertion->rule[0][0]]];
                         }
                     }
+                } elseif (is_string($assertion->var_id)
+                    && strpos($assertion->var_id, '$this->') === 0
+                    && $expr instanceof PhpParser\Node\Expr\MethodCall
+                ) {
+                    if ($prefix === $assertion->rule[0][0][0]) {
+                        $if_types[$assertion->var_id] = [[substr($assertion->rule[0][0], 1)]];
+                    } else {
+                        $if_types[$assertion->var_id] = [[$prefix . $assertion->rule[0][0]]];
+                    }
                 }
             }
         }
@@ -1901,6 +1910,15 @@ protected static function processCustomAssertion(
                             $if_types[$var_id] = [[$negated_prefix . $assertion->rule[0][0]]];
                         }
                     }
+                } elseif (is_string($assertion->var_id)
+                    && strpos($assertion->var_id, '$this->') === 0
+                    && $expr instanceof PhpParser\Node\Expr\MethodCall
+                ) {
+                    if ($prefix === $assertion->rule[0][0][0]) {
+                        $if_types[$assertion->var_id] = [[substr($assertion->rule[0][0], 1)]];
+                    } else {
+                        $if_types[$assertion->var_id] = [[$negated_prefix . $assertion->rule[0][0]]];
+                    }
                 }
             }
         }
diff --git a/tests/AssertTest.php b/tests/AssertTest.php
index b0548969fc8..10555d608eb 100644
--- a/tests/AssertTest.php
+++ b/tests/AssertTest.php
@@ -574,6 +574,98 @@ function takesIntOrIterable($v) : int {
                         return $v;
                     }'
             ],
+            'assertIfTrueOnProperty' => [
+                '<?php
+                    class A {
+                        public function foo() : void {}
+                    }
+
+                    class B {
+                        private ?A $a = null;
+
+                        public function bar() : void {
+                            if ($this->assertProperty()) {
+                                $this->a->foo();
+                            }
+                        }
+
+                        /**
+                         * @psalm-assert-if-true !null $this->a
+                         */
+                        public function assertProperty() : bool {
+                            return $this->a !== null;
+                        }
+                    }'
+            ],
+            'assertIfFalseOnProperty' => [
+                '<?php
+                    class A {
+                        public function foo() : void {}
+                    }
+
+                    class B {
+                        private ?A $a = null;
+
+                        public function bar() : void {
+                            if ($this->assertProperty()) {
+                                $this->a->foo();
+                            }
+                        }
+
+                        /**
+                         * @psalm-assert-if-false null $this->a
+                         */
+                        public function assertProperty() : bool {
+                            return $this->a !== null;
+                        }
+                    }'
+            ],
+            'assertIfTrueOnPropertyNegated' => [
+                '<?php
+                    class A {
+                        public function foo() : void {}
+                    }
+
+                    class B {
+                        private ?A $a = null;
+
+                        public function bar() : void {
+                            if (!$this->assertProperty()) {
+                                $this->a->foo();
+                            }
+                        }
+
+                        /**
+                         * @psalm-assert-if-true null $this->a
+                         */
+                        public function assertProperty() : bool {
+                            return $this->a !== null;
+                        }
+                    }'
+            ],
+            'assertIfFalseOnPropertyNegated' => [
+                '<?php
+                    class A {
+                        public function foo() : void {}
+                    }
+
+                    class B {
+                        private ?A $a = null;
+
+                        public function bar() : void {
+                            if (!$this->assertProperty()) {
+                                $this->a->foo();
+                            }
+                        }
+
+                        /**
+                         * @psalm-assert-if-false !null $this->a
+                         */
+                        public function assertProperty() : bool {
+                            return $this->a !== null;
+                        }
+                    }'
+            ],
         ];
     }