From 1173dcc6a2c14e683db73db15868d4da6139a7f6 Mon Sep 17 00:00:00 2001
From: Matt Brown <github@muglug.com>
Date: Tue, 28 Nov 2017 17:42:00 -0500
Subject: [PATCH] =?UTF-8?q?Don=E2=80=99t=20stop=20reconciling=20types=20wh?=
 =?UTF-8?q?en=20encountering=20problem?=
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---
 .../Checker/Statements/Block/IfChecker.php    | 28 -------------------
 src/Psalm/Checker/TypeChecker.php             |  5 ++--
 tests/PropertyTypeTest.php                    | 22 +++++++++++++++
 3 files changed, 25 insertions(+), 30 deletions(-)

diff --git a/src/Psalm/Checker/Statements/Block/IfChecker.php b/src/Psalm/Checker/Statements/Block/IfChecker.php
index f4f331c10..d3ac145dc 100644
--- a/src/Psalm/Checker/Statements/Block/IfChecker.php
+++ b/src/Psalm/Checker/Statements/Block/IfChecker.php
@@ -160,10 +160,6 @@ class IfChecker
                     $statements_checker->getSuppressedIssues()
                 );
 
-            if ($if_vars_in_scope_reconciled === false) {
-                return false;
-            }
-
             $if_context->vars_in_scope = $if_vars_in_scope_reconciled;
             $if_context->vars_possibly_in_scope = array_merge(
                 $reconcilable_if_types,
@@ -201,10 +197,6 @@ class IfChecker
                 $statements_checker->getSuppressedIssues()
             );
 
-            if ($else_vars_reconciled === false) {
-                return false;
-            }
-
             $temp_else_context->vars_in_scope = $else_vars_reconciled;
         }
 
@@ -472,10 +464,6 @@ class IfChecker
                     );
                 }
 
-                if ($outer_context_vars_reconciled === false) {
-                    return false;
-                }
-
                 $outer_context->vars_in_scope = $outer_context_vars_reconciled;
                 $mic_drop = true;
             }
@@ -579,10 +567,6 @@ class IfChecker
                 $statements_checker->getSuppressedIssues()
             );
 
-            if ($elseif_vars_reconciled === false) {
-                return false;
-            }
-
             $elseif_context->vars_in_scope = $elseif_vars_reconciled;
 
             if ($changed_var_ids) {
@@ -674,10 +658,6 @@ class IfChecker
                 $statements_checker->getSuppressedIssues()
             );
 
-            if ($elseif_vars_reconciled === false) {
-                return false;
-            }
-
             $elseif_context->vars_in_scope = $elseif_vars_reconciled;
 
             if ($changed_var_ids) {
@@ -820,10 +800,6 @@ class IfChecker
                         $statements_checker->getSuppressedIssues()
                     );
 
-                    if ($leaving_vars_reconciled === false) {
-                        return false;
-                    }
-
                     $implied_outer_context = clone $elseif_context;
                     $implied_outer_context->vars_in_scope = $leaving_vars_reconciled;
 
@@ -944,10 +920,6 @@ class IfChecker
                 $statements_checker->getSuppressedIssues()
             );
 
-            if ($else_vars_reconciled === false) {
-                return false;
-            }
-
             $else_context->vars_in_scope = $else_vars_reconciled;
 
             $else_context->removeReconciledClauses($changed_var_ids);
diff --git a/src/Psalm/Checker/TypeChecker.php b/src/Psalm/Checker/TypeChecker.php
index 14bd1740f..25947861f 100644
--- a/src/Psalm/Checker/TypeChecker.php
+++ b/src/Psalm/Checker/TypeChecker.php
@@ -38,7 +38,7 @@ class TypeChecker
      * @param  CodeLocation              $code_location
      * @param  array<string>             $suppressed_issues
      *
-     * @return array<string, Type\Union>|false
+     * @return array<string, Type\Union>
      */
     public static function reconcileKeyedTypes(
         array $new_types,
@@ -111,7 +111,8 @@ class TypeChecker
                     }
 
                     if ($result_type_candidate === false) {
-                        return false;
+                        $failed_reconciliation = true;
+                        $result_type_candidate = Type::getMixed();
                     }
 
                     $orred_type = $orred_type
diff --git a/tests/PropertyTypeTest.php b/tests/PropertyTypeTest.php
index f80db3ec7..91baebca2 100644
--- a/tests/PropertyTypeTest.php
+++ b/tests/PropertyTypeTest.php
@@ -353,6 +353,28 @@ class PropertyTypeTest extends TestCase
                         bar(A::$a[$b]);
                     }',
             ],
+            'staticPropertyArrayIssetAssertionWithVariableOffsetAndElse' => [
+                '<?php
+                    function bar(string $s) : void { }
+
+                    class A {
+                        /** @var array<string, string> */
+                        public static $a = [];
+                    }
+
+                    function foo() : void {
+                        $b = "hello";
+
+                        if (!isset(A::$a[$b])) {
+                            $g = "bar";
+                        } else {
+                            bar(A::$a[$b]);
+                            $g = "foo";
+                        }
+
+                        bar($g);
+                    }',
+            ],
             'traitConstructor' => [
                 '<?php
                     trait T {