feat(expect): adds toBe

src/Expectation.php

@@ -0,0 +1,65 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Pest;
+
+use PHPUnit\Framework\Assert;
+
+/**
+ * @internal
+ *
+ * @property Expectation $not Creates the opposite expectation.
+ */
+final class Expectation
+{
+    /**
+     * The expectation value.
+     *
+     * @var mixed
+     */
+    private $value;
+
+    /**
+     * Creates a new expectation.
+     *
+     * @param mixed $value
+     */
+    public function __construct($value)
+    {
+        $this->value = $value;
+    }
+
+    /**
+     * Creates the opposite expectation for the value.
+     */
+    public function not(): OppositeExpectation
+    {
+        return new OppositeExpectation($this);
+    }
+
+    /**
+     * Asserts that two variables have the same type and
+     * value. Used on objects, it asserts that two
+     * variables reference the same object.
+     *
+     * @param mixed $value
+     */
+    public function toBe($value): Expectation
+    {
+        Assert::assertSame($value, $this->value);
+
+        return $this;
+    }
+
+    /**
+     * Dynamically calls methods on the class without any arguments.
+     *
+     * @return Expectation
+     */
+    public function __get(string $name)
+    {
+        /* @phpstan-ignore-next-line */
+        return $this->{$name}();
+    }
+}