Merge pull request #9 from lukeraymonddowning/master

Adds a `sequence` method for traversable values

src/Each.php

@@ -4,6 +4,8 @@
 
 namespace Pest\Expectations;
 
+use BadMethodCallException;
+
 /**
  * @internal
  *
@@ -29,6 +31,35 @@ public function __construct(Expectation $original)
         $this->original = $original;
     }
 
+    /**
+     * Allows you to specify a sequential set of
+     * expectations for each item in a
+     * traversable "value".
+     *
+     * @param callable ...$expectations
+     */
+    public function sequence(...$expectations): Each
+    {
+        if (!is_iterable($this->original->value)) {
+            throw new BadMethodCallException('Expectation value is not traversable.');
+        }
+
+        $expectationIndex = 0;
+
+        /* @phpstan-ignore-next-line */
+        while (count($expectations) < count($this->original->value)) {
+            $expectations[] = $expectations[$expectationIndex];
+            /* @phpstan-ignore-next-line */
+            $expectationIndex = $expectationIndex < count($this->original->value) - 1 ? $expectationIndex + 1 : 0;
+        }
+
+        foreach ($this->original->value as $index => $item) {
+            call_user_func($expectations[$index], expect($item));
+        }
+
+        return $this;
+    }
+
     /**
      * Creates a new expectation.
      *

tests/Expect/sequence.php

@@ -0,0 +1,41 @@
+<?php
+
+test('an exception is thrown if the the type is not iterable', function () {
+    expect('Foobar')->each->sequence();
+})->throws(BadMethodCallException::class, 'Expectation value is not traversable.');
+
+test('allows for sequences of checks to be run on traversable data', function () {
+    expect([1, 2, 3])
+        ->each
+        ->sequence(
+            function ($expectation) { $expectation->toBeInt()->toEqual(1); },
+            function ($expectation) { $expectation->toBeInt()->toEqual(2); },
+            function ($expectation) { $expectation->toBeInt()->toEqual(3); },
+        );
+
+    expect(static::getCount())->toBe(6);
+});
+
+test('loops back to the start if it runs out of sequence items', function () {
+    expect([1, 2, 3, 1, 2, 3, 1, 2])
+        ->each
+        ->sequence(
+            function ($expectation) { $expectation->toBeInt()->toEqual(1); },
+            function ($expectation) { $expectation->toBeInt()->toEqual(2); },
+            function ($expectation) { $expectation->toBeInt()->toEqual(3); },
+        );
+
+    expect(static::getCount())->toBe(16);
+});
+
+test('it works if the number of items in the traversable is smaller than the number of expectations', function () {
+    expect([1, 2])
+        ->each
+        ->sequence(
+            function ($expectation) { $expectation->toBeInt()->toEqual(1); },
+            function ($expectation) { $expectation->toBeInt()->toEqual(2); },
+            function ($expectation) { $expectation->toBeInt()->toEqual(3); },
+        );
+
+    expect(static::getCount())->toBe(4);
+});