From 7c10a09ead7fc4a4254b49249503abb21588984e Mon Sep 17 00:00:00 2001
From: Matthew Brown <github@muglug.com>
Date: Wed, 8 Aug 2018 22:33:31 -0400
Subject: [PATCH] Fix #911 - properly substitute alias types

Also improve handling of array_splice
---
 .../Statements/Expression/CallChecker.php     | 80 ++++++++++++++++++-
 .../Checker/Statements/ReturnChecker.php      |  5 +-
 src/Psalm/Type.php                            |  7 +-
 3 files changed, 86 insertions(+), 6 deletions(-)

diff --git a/src/Psalm/Checker/Statements/Expression/CallChecker.php b/src/Psalm/Checker/Statements/Expression/CallChecker.php
index 784923c37..c70a85c7a 100644
--- a/src/Psalm/Checker/Statements/Expression/CallChecker.php
+++ b/src/Psalm/Checker/Statements/Expression/CallChecker.php
@@ -346,6 +346,84 @@ class CallChecker
             return;
         }
 
+        if ($method_id && $method_id === 'array_splice' && $function_params && count($args) > 1) {
+            $array_arg = $args[0]->value;
+
+            if (ExpressionChecker::analyze(
+                $statements_checker,
+                $array_arg,
+                $context
+            ) === false) {
+                return false;
+            }
+
+            $offset_arg = $args[1]->value;
+
+            if (ExpressionChecker::analyze(
+                $statements_checker,
+                $offset_arg,
+                $context
+            ) === false) {
+                return false;
+            }
+
+            if (!isset($args[2]) || !isset($args[3])) {
+                return;
+            }
+
+            $length_arg = $args[2]->value;
+
+            if (ExpressionChecker::analyze(
+                $statements_checker,
+                $length_arg,
+                $context
+            ) === false) {
+                return false;
+            }
+
+            $replacement_arg = $args[3]->value;
+
+            if (ExpressionChecker::analyze(
+                $statements_checker,
+                $replacement_arg,
+                $context
+            ) === false) {
+                return false;
+            }
+
+            if (isset($array_arg->inferredType)
+                && $array_arg->inferredType->hasArray()
+                && isset($replacement_arg->inferredType)
+                && $replacement_arg->inferredType->hasArray()
+            ) {
+                /** @var TArray|ObjectLike */
+                $array_type = $array_arg->inferredType->getTypes()['array'];
+
+                if ($array_type instanceof ObjectLike) {
+                    $array_type = $array_type->getGenericArrayType();
+                }
+
+                /** @var TArray|ObjectLike */
+                $replacement_array_type = $replacement_arg->inferredType->getTypes()['array'];
+
+                if ($replacement_array_type instanceof ObjectLike) {
+                    $replacement_array_type = $replacement_array_type->getGenericArrayType();
+                }
+
+                $by_ref_type = Type\TypeCombination::combineTypes([$array_type, $replacement_array_type]);
+
+                ExpressionChecker::assignByRefParam(
+                    $statements_checker,
+                    $array_arg,
+                    $by_ref_type,
+                    $context,
+                    false
+                );
+            }
+
+            return;
+        }
+
         foreach ($args as $argument_offset => $arg) {
             if ($function_params !== null) {
                 $by_ref = $argument_offset < count($function_params)
@@ -712,7 +790,7 @@ class CallChecker
                         'shuffle', 'sort', 'rsort', 'usort', 'ksort', 'asort',
                         'krsort', 'arsort', 'natcasesort', 'natsort', 'reset',
                         'end', 'next', 'prev', 'array_pop', 'array_shift',
-                        'array_push', 'array_unshift', 'socket_select',
+                        'array_push', 'array_unshift', 'socket_select', 'array_splice',
                     ],
                     true
                 )) {
diff --git a/src/Psalm/Checker/Statements/ReturnChecker.php b/src/Psalm/Checker/Statements/ReturnChecker.php
index c97c2d5c8..9dd462312 100644
--- a/src/Psalm/Checker/Statements/ReturnChecker.php
+++ b/src/Psalm/Checker/Statements/ReturnChecker.php
@@ -245,8 +245,9 @@ class ReturnChecker
                         } else {
                             if (IssueBuffer::accepts(
                                 new InvalidReturnStatement(
-                                    'The type \'' . $stmt->inferredType . '\' does not match the declared return '
-                                        . 'type \'' . $local_return_type . '\' for ' . $cased_method_id,
+                                    'The type \'' . $stmt->inferredType->getId()
+                                        . '\' does not match the declared return '
+                                        . 'type \'' . $local_return_type->getId() . '\' for ' . $cased_method_id,
                                     new CodeLocation($source, $stmt)
                                 ),
                                 $statements_checker->getSuppressedIssues()
diff --git a/src/Psalm/Type.php b/src/Psalm/Type.php
index cda6a259e..71cbcd08b 100644
--- a/src/Psalm/Type.php
+++ b/src/Psalm/Type.php
@@ -643,11 +643,12 @@ abstract class Type
             if (isset($type_aliases[$string_type_token])) {
                 $replacement_tokens = $type_aliases[$string_type_token];
 
+                array_unshift($replacement_tokens, '(');
+                array_push($replacement_tokens, ')');
+
                 $diff = count($replacement_tokens) - 1;
 
-                for ($j = 0; $j < $diff + 1; $j++) {
-                    $type_tokens[$i + $j] = $replacement_tokens[$j];
-                }
+                array_splice($type_tokens, $i, 1, $replacement_tokens);
 
                 $i += $diff;
                 $l += $diff;