Update outer clauses in mic drop situation

src/Psalm/Checker/Statements/Block/IfChecker.php

@@ -177,6 +177,7 @@ class IfChecker
             $if_context,
             $old_if_context,
             $context,
+            $negated_clauses,
             $pre_assignment_else_redefined_vars
         );
 
@@ -272,6 +273,7 @@ class IfChecker
      * @param  Context                  $if_context
      * @param  Context                  $old_if_context
      * @param  Context                  $outer_context
+     * @param  array<Clause>            $negated_clauses
      * @param  array<string,Type\Union> $pre_assignment_else_redefined_vars
      * @return false|null
      */
@@ -282,6 +284,7 @@ class IfChecker
         Context $if_context,
         Context $old_if_context,
         Context $outer_context,
+        array $negated_clauses,
         array $pre_assignment_else_redefined_vars
     ) {
         $has_ending_statements = ScopeChecker::doesAlwaysReturnOrThrow($stmt->stmts);
@@ -338,28 +341,34 @@ class IfChecker
 
             $if_scope->redefined_vars = Context::getRedefinedVars($outer_context, $if_context);
             $if_scope->possibly_redefined_vars = $if_scope->redefined_vars;
-        } elseif (!$stmt->else && !$stmt->elseifs && $if_scope->negated_types) {
+        } elseif (!$stmt->else && !$stmt->elseifs) {
-            $changed_vars = [];
+            if ($if_scope->negated_types) {
+                $changed_vars = [];
 
-            $outer_context_vars_reconciled = TypeChecker::reconcileKeyedTypes(
+                $outer_context_vars_reconciled = TypeChecker::reconcileKeyedTypes(
-                $if_scope->negated_types,
+                    $if_scope->negated_types,
-                $outer_context->vars_in_scope,
+                    $outer_context->vars_in_scope,
-                $changed_vars,
+                    $changed_vars,
-                $statements_checker->getFileChecker(),
+                    $statements_checker->getFileChecker(),
-                new CodeLocation($statements_checker->getSource(), $stmt->cond),
+                    new CodeLocation($statements_checker->getSource(), $stmt->cond),
-                $statements_checker->getSuppressedIssues()
+                    $statements_checker->getSuppressedIssues()
+                );
+
+                foreach ($changed_vars as $changed_var) {
+                    $outer_context->removeVarFromClauses($changed_var);
+                }
+
+                if ($outer_context_vars_reconciled === false) {
+                    return false;
+                }
+
+                $outer_context->vars_in_scope = $outer_context_vars_reconciled;
+                $mic_drop = true;
+            }
+
+            $outer_context->clauses = TypeChecker::simplifyCNF(
+                array_merge($outer_context->clauses, $negated_clauses)
             );
-
-            foreach ($changed_vars as $changed_var) {
-                $outer_context->removeVarFromClauses($changed_var);
-            }
-
-            if ($outer_context_vars_reconciled === false) {
-                return false;
-            }
-
-            $outer_context->vars_in_scope = $outer_context_vars_reconciled;
-            $mic_drop = true;
         }
 
         // update the parent context as necessary, but only if we can safely reason about type negation.
@@ -902,10 +911,6 @@ class IfChecker
             return $stmt;
         }
 
-        if ($stmt instanceof PhpParser\Node\Expr\BinaryOp) {
-            return self::getDefinitelyEvaluatedExpression($stmt->left);
-        }
-
         if ($stmt instanceof PhpParser\Node\Expr\BooleanNot) {
             return self::getDefinitelyEvaluatedExpression($stmt->expr);
         }

src/Psalm/Checker/StatementsChecker.php

@@ -416,6 +416,8 @@ class StatementsChecker extends SourceChecker implements StatementsSource
                     unset($loop_context->vars_in_scope[$var_id]);
                 }
 
+                $loop_context->clauses = $pre_loop_context->clauses;
+
                 IssueBuffer::startRecording();
                 $this->analyze($stmts, $loop_context, $outer_context);
                 $recorded_issues = IssueBuffer::clearRecordingLevel();

tests/ScopeTest.php

@@ -413,121 +413,6 @@ class ScopeTest extends PHPUnit_Framework_TestCase
         $file_checker->visitAndAnalyzeMethods();
     }
 
-    /**
-     * @return void
-     */
-    public function testTwoVarLogic()
-    {
-        $stmts = self::$parser->parse('<?php
-        $a = rand(0, 10) ? "hello" : null;
-        $b = rand(0, 10) ? "goodbye" : null;
-
-        if ($a !== null || $b !== null) {
-            if ($a !== null) {
-                $c = $a;
-            } else {
-                $c = $b;
-            }
-
-            echo strpos($c, "e");
-        }
-        ');
-
-        $file_checker = new FileChecker('somefile.php', $this->project_checker, $stmts);
-        $file_checker->visitAndAnalyzeMethods();
-    }
-
-    /**
-     * @return void
-     */
-    public function testThreeVarLogic()
-    {
-        $stmts = self::$parser->parse('<?php
-        $a = rand(0, 10) ? "hello" : null;
-        $b = rand(0, 10) ? "goodbye" : null;
-        $c = rand(0, 10) ? "hello" : null;
-
-        if ($a !== null || $b !== null || $c !== null) {
-            if ($a !== null) {
-                $d = $a;
-            } elseif ($b !== null) {
-                $d = $b;
-            } else {
-                $d = $c;
-            }
-
-            echo strpos($d, "e");
-        }
-        ');
-
-        $file_checker = new FileChecker('somefile.php', $this->project_checker, $stmts);
-        $file_checker->visitAndAnalyzeMethods();
-    }
-
-    /**
-     * @expectedException        \Psalm\Exception\CodeException
-     * @expectedExceptionMessage NullArgument
-     * @return                   void
-     */
-    public function testThreeVarLogicWithChange()
-    {
-        $stmts = self::$parser->parse('<?php
-        $a = rand(0, 10) ? "hello" : null;
-        $b = rand(0, 10) ? "goodbye" : null;
-        $c = rand(0, 10) ? "hello" : null;
-
-        if ($a !== null || $b !== null || $c !== null) {
-            $c = null;
-
-            if ($a !== null) {
-                $d = $a;
-            } elseif ($b !== null) {
-                $d = $b;
-            } else {
-                $d = $c;
-            }
-
-            echo strpos($d, "e");
-        }
-        ');
-
-        $file_checker = new FileChecker('somefile.php', $this->project_checker, $stmts);
-        $file_checker->visitAndAnalyzeMethods();
-    }
-
-    /**
-     * @expectedException        \Psalm\Exception\CodeException
-     * @expectedExceptionMessage NullArgument
-     * @return                   void
-     */
-    public function testThreeVarLogicWithException()
-    {
-        $stmts = self::$parser->parse('<?php
-        $a = rand(0, 10) ? "hello" : null;
-        $b = rand(0, 10) ? "goodbye" : null;
-        $c = rand(0, 10) ? "hello" : null;
-
-        if ($a !== null || $b !== null || $c !== null) {
-            if ($c !== null) {
-                throw new \Exception("bad");
-            }
-
-            if ($a !== null) {
-                $d = $a;
-            } elseif ($b !== null) {
-                $d = $b;
-            } else {
-                $d = $c;
-            }
-
-            echo strpos($d, "e");
-        }
-        ');
-
-        $file_checker = new FileChecker('somefile.php', $this->project_checker, $stmts);
-        $file_checker->visitAndAnalyzeMethods();
-    }
-
     /**
      * @return void
      */

tests/TypeAlgebraTest.php

@@ -0,0 +1,171 @@
+<?php
+namespace Psalm\Tests;
+
+use PhpParser\ParserFactory;
+use PHPUnit_Framework_TestCase;
+use Psalm\Checker\FileChecker;
+use Psalm\Config;
+use Psalm\Context;
+
+class TypeAlgebraTest extends PHPUnit_Framework_TestCase
+{
+    /** @var \PhpParser\Parser */
+    protected static $parser;
+
+    /** @var TestConfig */
+    protected static $config;
+
+    /** @var \Psalm\Checker\ProjectChecker */
+    protected $project_checker;
+
+    /**
+     * @return void
+     */
+    public static function setUpBeforeClass()
+    {
+        self::$parser = (new ParserFactory)->create(ParserFactory::PREFER_PHP7);
+        self::$config = new TestConfig();
+    }
+
+    /**
+     * @return void
+     */
+    public function setUp()
+    {
+        FileChecker::clearCache();
+        $this->project_checker = new \Psalm\Checker\ProjectChecker();
+        $this->project_checker->setConfig(self::$config);
+    }
+
+    /**
+     * @return void
+     */
+    public function testTwoVarLogic()
+    {
+        $stmts = self::$parser->parse('<?php
+        $a = rand(0, 10) ? "hello" : null;
+        $b = rand(0, 10) ? "goodbye" : null;
+
+        if ($a !== null || $b !== null) {
+            if ($a !== null) {
+                $c = $a;
+            } else {
+                $c = $b;
+            }
+
+            echo strpos($c, "e");
+        }
+        ');
+
+        $file_checker = new FileChecker('somefile.php', $this->project_checker, $stmts);
+        $file_checker->visitAndAnalyzeMethods();
+    }
+
+    /**
+     * @return void
+     */
+    public function testThreeVarLogic()
+    {
+        $stmts = self::$parser->parse('<?php
+        $a = rand(0, 10) ? "hello" : null;
+        $b = rand(0, 10) ? "goodbye" : null;
+        $c = rand(0, 10) ? "hello" : null;
+
+        if ($a !== null || $b !== null || $c !== null) {
+            if ($a !== null) {
+                $d = $a;
+            } elseif ($b !== null) {
+                $d = $b;
+            } else {
+                $d = $c;
+            }
+
+            echo strpos($d, "e");
+        }
+        ');
+
+        $file_checker = new FileChecker('somefile.php', $this->project_checker, $stmts);
+        $file_checker->visitAndAnalyzeMethods();
+    }
+
+    /**
+     * @expectedException        \Psalm\Exception\CodeException
+     * @expectedExceptionMessage NullArgument
+     * @return                   void
+     */
+    public function testThreeVarLogicWithChange()
+    {
+        $stmts = self::$parser->parse('<?php
+        $a = rand(0, 10) ? "hello" : null;
+        $b = rand(0, 10) ? "goodbye" : null;
+        $c = rand(0, 10) ? "hello" : null;
+
+        if ($a !== null || $b !== null || $c !== null) {
+            $c = null;
+
+            if ($a !== null) {
+                $d = $a;
+            } elseif ($b !== null) {
+                $d = $b;
+            } else {
+                $d = $c;
+            }
+
+            echo strpos($d, "e");
+        }
+        ');
+
+        $file_checker = new FileChecker('somefile.php', $this->project_checker, $stmts);
+        $file_checker->visitAndAnalyzeMethods();
+    }
+
+    /**
+     * @expectedException        \Psalm\Exception\CodeException
+     * @expectedExceptionMessage NullArgument
+     * @return                   void
+     */
+    public function testThreeVarLogicWithException()
+    {
+        $stmts = self::$parser->parse('<?php
+        $a = rand(0, 10) ? "hello" : null;
+        $b = rand(0, 10) ? "goodbye" : null;
+        $c = rand(0, 10) ? "hello" : null;
+
+        if ($a !== null || $b !== null || $c !== null) {
+            if ($c !== null) {
+                throw new \Exception("bad");
+            }
+
+            if ($a !== null) {
+                $d = $a;
+            } elseif ($b !== null) {
+                $d = $b;
+            } else {
+                $d = $c;
+            }
+
+            echo strpos($d, "e");
+        }
+        ');
+
+        $file_checker = new FileChecker('somefile.php', $this->project_checker, $stmts);
+        $file_checker->visitAndAnalyzeMethods();
+    }
+
+    /**
+     * @return void
+     */
+    public function testTwoVarLogicNotNested()
+    {
+        $stmts = self::$parser->parse('<?php
+        function foo(?string $a, ?string $b) : string {
+            if (!$a && !$b) return "bad";
+            if (!$a) return $b;
+            return $a;
+        }
+        ');
+
+        $file_checker = new FileChecker('somefile.php', $this->project_checker, $stmts);
+        $file_checker->visitAndAnalyzeMethods();
+    }
+}