From 63a0e768b378f5af3a1d86d5614e917e43d8defd Mon Sep 17 00:00:00 2001
From: Matthew Brown <github@muglug.com>
Date: Mon, 25 Mar 2019 22:30:40 -0400
Subject: [PATCH] Improve type coverage in both good and bad ways

---
 phpunit.xml.dist                              |   3 +
 .../Statements/Expression/AssertionFinder.php |  25 +----
 tests/AssignmentTest.php                      |   6 ++
 tests/EmptyTest.php                           |   8 ++
 tests/RedundantConditionTest.php              | 101 ++++++++++++++++++
 5 files changed, 120 insertions(+), 23 deletions(-)

diff --git a/phpunit.xml.dist b/phpunit.xml.dist
index 09cf856d8..dba10ab56 100644
--- a/phpunit.xml.dist
+++ b/phpunit.xml.dist
@@ -19,6 +19,8 @@
                 <directory suffix=".php">src/Psalm/Issue/</directory>
                 <directory suffix=".php">src/Psalm/Internal/Stubs/</directory>
                 <directory suffix=".php">src/Psalm/Internal/LanguageServer/</directory>
+                <directory suffix=".php">src/Psalm/Internal/ExecutionEnvironment/</directory>
+                <directory suffix=".php">src/Psalm/SourceControl/</directory>
                 <file>src/command_functions.php</file>
                 <file>src/psalm.php</file>
                 <file>src/psalm-language-server.php</file>
@@ -26,6 +28,7 @@
                 <file>src/psalm_plugin.php</file>
                 <file>src/Psalm/Internal/CallMap.php</file>
                 <file>src/Psalm/Internal/Fork/Pool.php</file>
+                <file>src/Psalm/Internal/Fork/Restarter.php</file>
                 <file>src/Psalm/Internal/PropertyMap.php</file>
                 <file>src/Psalm/Internal/Provider/ClassLikeStorageCacheProvider.php</file>
                 <file>src/Psalm/Internal/Provider/FileReferenceCacheProvider.php</file>
diff --git a/src/Psalm/Internal/Analyzer/Statements/Expression/AssertionFinder.php b/src/Psalm/Internal/Analyzer/Statements/Expression/AssertionFinder.php
index d214d508c..c36c72b4d 100644
--- a/src/Psalm/Internal/Analyzer/Statements/Expression/AssertionFinder.php
+++ b/src/Psalm/Internal/Analyzer/Statements/Expression/AssertionFinder.php
@@ -180,8 +180,6 @@ class AssertionFinder
             if ($count_equality_position) {
                 if ($count_equality_position === self::ASSIGNMENT_TO_RIGHT) {
                     $counted_expr = $conditional->left;
-                } elseif ($count_equality_position === self::ASSIGNMENT_TO_LEFT) {
-                    $counted_expr = $conditional->right;
                 } else {
                     throw new \UnexpectedValueException('$count_equality_position value');
                 }
@@ -238,9 +236,7 @@ class AssertionFinder
             $typed_value_position = self::hasTypedValueComparison($conditional);
 
             if ($count_equality_position) {
-                if ($count_equality_position === self::ASSIGNMENT_TO_RIGHT) {
-                    $count_expr = $conditional->left;
-                } elseif ($count_equality_position === self::ASSIGNMENT_TO_LEFT) {
+                if ($count_equality_position === self::ASSIGNMENT_TO_LEFT) {
                     $count_expr = $conditional->right;
                 } else {
                     throw new \UnexpectedValueException('$count_equality_position value');
@@ -306,23 +302,6 @@ class AssertionFinder
 
             if ($var_name) {
                 $if_types[$var_name] = [['empty']];
-            } else {
-                // look for any variables we *can* use for an isset assertion
-                $array_root = $conditional->expr;
-
-                while ($array_root instanceof PhpParser\Node\Expr\ArrayDimFetch && !$var_name) {
-                    $array_root = $array_root->var;
-
-                    $var_name = ExpressionAnalyzer::getArrayVarId(
-                        $array_root,
-                        $this_class_name,
-                        $source
-                    );
-                }
-
-                if ($var_name) {
-                    $if_types[$var_name] = [['=empty']];
-                }
             }
 
             $conditional->assertions = $if_types;
@@ -718,7 +697,7 @@ class AssertionFinder
                         }
                     } else {
                         if (IssueBuffer::accepts(
-                            new TypeDoesNotContainNull(
+                            new TypeDoesNotContainType(
                                 $var_type . ' does not contain empty array',
                                 new CodeLocation($source, $conditional)
                             ),
diff --git a/tests/AssignmentTest.php b/tests/AssignmentTest.php
index 673be223e..74c230331 100644
--- a/tests/AssignmentTest.php
+++ b/tests/AssignmentTest.php
@@ -45,6 +45,12 @@ class AssignmentTest extends TestCase
                         echo $x;
                     }',
             ],
+            'ifAssignment' => [
+                '<?php
+                    if ($foo = rand(0, 1)) {
+                        echo $foo;
+                    }',
+            ],
         ];
     }
 
diff --git a/tests/EmptyTest.php b/tests/EmptyTest.php
index 6a13dd32b..2bb6c98b5 100644
--- a/tests/EmptyTest.php
+++ b/tests/EmptyTest.php
@@ -335,6 +335,14 @@ class EmptyTest extends TestCase
                         if (empty($arr[$i]) && empty($arr[$j])) {}
                     }',
             ],
+            'checkArrayEmptyUnknownRoot' => [
+                '<?php
+                    function foo(array $arr) : void {
+                        if (empty($arr[rand(0, 1)])) {
+                            if ($arr) {}
+                        }
+                    }',
+            ],
         ];
     }
 
diff --git a/tests/RedundantConditionTest.php b/tests/RedundantConditionTest.php
index 8e2e594f2..e09158d74 100644
--- a/tests/RedundantConditionTest.php
+++ b/tests/RedundantConditionTest.php
@@ -560,6 +560,18 @@ class RedundantConditionTest extends TestCase
                         assert(is_int($a[0]));
                     }',
             ],
+            'allowChecksOnFalsyIf' => [
+                '<?php
+                    function foo(?string $s) : string {
+                        if ($s == null) {
+                            if ($s === null) {}
+
+                            return "hello";
+                        } else {
+                            return $s;
+                        }
+                    }'
+            ],
         ];
     }
 
@@ -865,6 +877,95 @@ class RedundantConditionTest extends TestCase
                     }',
                 'error_message' => 'RedundantCondition',
             ],
+            'redundantInstanceof' => [
+                '<?php
+                    /** @param Exception $a */
+                    function foo($a) : void {
+                        if ($a instanceof \Exception) {}
+                    }',
+                'error_message' => 'RedundantConditionGivenDocblockType',
+            ],
+            'preventDocblockTypesBeingIdenticalToTrue' => [
+                '<?php
+                    class A {}
+
+                    /**
+                     * @param  A $a
+                     */
+                    function foo($a, $b) : void {
+                        if ($a === true) {}
+                    }',
+                'error_message' => 'DocblockTypeContradiction',
+            ],
+            'preventDocblockTypesBeingIdenticalToTrueReversed' => [
+                '<?php
+                    class A {}
+
+                    /**
+                     * @param  A $a
+                     */
+                    function foo($a, $b) : void {
+                        if (true === $a) {}
+                    }',
+                'error_message' => 'DocblockTypeContradiction',
+            ],
+            'preventDocblockTypesBeingIdenticalToFalse' => [
+                '<?php
+                    class A {}
+
+                    /**
+                     * @param  A $a
+                     */
+                    function foo($a, $b) : void {
+                        if ($a === false) {}
+                    }',
+                'error_message' => 'DocblockTypeContradiction',
+            ],
+            'preventDocblockTypesBeingIdenticalToFalseReversed' => [
+                '<?php
+                    class A {}
+
+                    /**
+                     * @param  A $a
+                     */
+                    function foo($a, $b) : void {
+                        if (false === $a) {}
+                    }',
+                'error_message' => 'DocblockTypeContradiction',
+            ],
+            'preventDocblockTypesBeingSameAsEmptyArrayReversed' => [
+                '<?php
+                    class A {}
+
+                    /**
+                     * @param  A $a
+                     */
+                    function foo($a, $b) : void {
+                        if ([] == $a) {}
+                    }',
+                'error_message' => 'DocblockTypeContradiction',
+            ],
+            'preventDocblockTypesBeingIdenticalToEmptyArrayReversed' => [
+                '<?php
+                    class A {}
+
+                    /**
+                     * @param  A $a
+                     */
+                    function foo($a, $b) : void {
+                        if ([] === $a) {}
+                    }',
+                'error_message' => 'DocblockTypeContradiction',
+            ],
+            'preventTypesBeingIdenticalToEmptyArrayReversed' => [
+                '<?php
+                    class A {}
+
+                    function foo(A $a, $b) : void {
+                        if ([] === $a) {}
+                    }',
+                'error_message' => 'TypeDoesNotContainType',
+            ],
         ];
     }
 }