[8.x] Add Str::pipe & make Stringable tappable

src/Illuminate/Support/Stringable.php

@@ -4,11 +4,12 @@
 
 use Closure;
 use Illuminate\Support\Traits\Macroable;
+use Illuminate\Support\Traits\Tappable;
 use Symfony\Component\VarDumper\VarDumper;
 
 class Stringable
 {
-    use Macroable;
+    use Tappable, Macroable;
 
     /**
      * The underlying string value.
@@ -399,6 +400,17 @@ public function parseCallback($default = null)
         return Str::parseCallback($this->value, $default);
     }
 
+    /**
+     * Call the given callback and return a new string.
+     *
+     * @param callable $callback
+     * @return static
+     */
+    public function pipe(callable $callback)
+    {
+        return new static(call_user_func($callback, $this));
+    }
+
     /**
      * Get the plural form of an English word.
      *

tests/Support/SupportStringableTest.php

@@ -545,4 +545,28 @@ public function testChunk()
         $this->assertInstanceOf(Collection::class, $chunks);
         $this->assertSame(['foo', 'bar', 'baz'], $chunks->all());
     }
+
+    public function testTap()
+    {
+        $stringable = $this->stringable('foobarbaz');
+
+        $fromTheTap = '';
+
+        $stringable = $stringable->tap(function (Stringable $string) use (&$fromTheTap) {
+            $fromTheTap = $string->substr(0, 3);
+        });
+
+        $this->assertSame('foo', (string) $fromTheTap);
+        $this->assertSame('foobarbaz', (string) $stringable);
+    }
+
+    public function testPipe()
+    {
+        $callback = function ($stringable) {
+            return 'bar';
+        };
+
+        $this->assertInstanceOf(Stringable::class, $this->stringable('foo')->pipe($callback));
+        $this->assertSame('bar', (string) $this->stringable('foo')->pipe($callback));
+    }
 }