Prevent nested arrays from causing array to string conversion when ca…

…sting Subset as a string

CHANGELOG.md

@@ -1,7 +1,8 @@
 # Change Log
 
-## 1.5.2 (2022-xx-xx)
+## 1.5.2 (2023-xx-xx)
 
+* Prevent array to string conversion when serialising a Subset matcher #1252
 * Updated changelog for version 1.5.1 to include changes from #1180
 
 ## 1.3.6 (2022-09-07)

library/Mockery/Matcher/Subset.php

@@ -81,12 +81,21 @@ public function match(&$actual)
      */
     public function __toString()
     {
-        $return = '<Subset[';
-        $elements = array();
-        foreach ($this->expected as $k=>$v) {
-            $elements[] = $k . '=' . (string) $v;
+        return '<Subset' . $this->formatArray($this->expected) . ">";
+    }
+
+    /**
+     * Recursively format an array into the string representation for this matcher
+     *
+     * @param array $array
+     * @return string
+     */
+    protected function formatArray(array $array)
+    {
+        $elements = [];
+        foreach ($array as $k => $v) {
+            $elements[] = $k . '=' . (is_array($v) ? $this->formatArray($v) : (string) $v);
         }
-        $return .= implode(', ', $elements) . ']>';
-        return $return;
+        return "[" . implode(", ", $elements) . "]";
     }
 }

tests/Mockery/Matcher/SubsetTest.php

@@ -94,4 +94,28 @@ public function it_returns_false_if_actual_is_not_an_array()
 
         $this->assertFalse($matcher->match($actual));
     }
+
+    /** @test */
+    public function it_correctly_formats_nested_arrays_into_a_string()
+    {
+        $expected = [
+            "foo" => 123,
+            "bar" => [
+                "baz" => 456
+            ]
+        ];
+
+        $matcher = new Subset($expected);
+        $actual = $matcher->__toString();
+
+        $tests = [
+            "/foo=123/",
+            "/bar=\\[[^[\\]]+\\]/", // e.g. bar=[<anything other than square brackets>]
+            "/baz=456/"
+        ];
+
+        foreach ($tests as $pattern) {
+            $this->assertMatchesRegularExpression($pattern, $actual);
+        }
+    }
 }