Implemented __toString() for argument matchers. (#260)

spec/Suite/Arg.spec.php

@@ -86,4 +86,43 @@
 
     });
 
+    describe("->__toString()", function () {
+
+        it("describes the argument matcher", function () {
+
+            $arg = Arg::toBe(true);
+            expect(strval($arg))->toBe('toBe(true)');
+
+        });
+
+        it("describes argument matchers with multiple arguments", function () {
+
+            $arg = Arg::toBeCloseTo(1, 2);
+            expect(strval($arg))->toBe('toBeCloseTo(1, 2)');
+
+        });
+
+        it("describes argument matchers with no arguments", function () {
+
+            $arg = Arg::toBeTruthy();
+            expect(strval($arg))->toBe('toBeTruthy()');
+
+        });
+
+        it("describes argument matchers with array arguments", function () {
+
+            $arg = Arg::toBe([1, 2]);
+            expect(strval($arg))->toBe('toBe(array[2])');
+
+        });
+
+        it("describes argument matchers with object arguments", function () {
+
+            $arg = Arg::toBe((object) [1, 2]);
+            expect(strval($arg))->toBe('toBe(object[stdClass])');
+
+        });
+
+    });
+
 });

src/Arg.php

@@ -2,6 +2,7 @@
 namespace Kahlan;
 
 use Exception;
+use Kahlan\Util\Text;
 
 /**
  * Class Arg
@@ -137,4 +138,39 @@ public function match($actual)
         $boolean = call_user_func_array($matcher . '::match', $args);
         return $this->_not ? !$boolean : $boolean;
     }
+
+    /**
+     * Returns the description of this argument matcher.
+     *
+     * @return string The description of this argument matcher.
+     */
+    public function __toString()
+    {
+        return sprintf(
+            '%s(%s)',
+            $this->_name,
+            implode(
+                ', ',
+                array_map([Arg::class, '_describeArg'], $this->_args)
+            )
+        );
+    }
+
+    /**
+     * Generate an inline string representation of an argument.
+     *
+     * @param mixed $arg The argument.
+     * @return string    The dumped string.
+     */
+    public static function _describeArg($arg)
+    {
+        if (is_array($arg)) {
+            return sprintf('array[%d]', count($arg));
+        }
+        if (is_object($arg)) {
+            return sprintf('object[%s]', get_class($arg));
+        }
+
+        return Text::toString($arg);
+    }
 }