add unit test files

tests/Packet/HeaderTest.php

@@ -0,0 +1,35 @@
+<?php
+declare(strict_types=1);
+
+namespace Tests\ArrayAccess\DnsRecord\Packet;
+
+use ArrayAccess\DnsRecord\Exceptions\LengthException;
+use ArrayAccess\DnsRecord\Packet\Header;
+use PHPUnit\Framework\TestCase;
+use Throwable;
+use function sprintf;
+
+class HeaderTest extends TestCase
+{
+    /**
+     * Just test header exception
+     *
+     * @see \Tests\ArrayAccess\DnsRecord\Utils\BufferTest::testCreateQuestionMessage()
+     */
+    public function testFromMessage()
+    {
+        try {
+            Header::fromMessage('');
+        } catch (Throwable $e) {
+            $this->assertInstanceOf(
+                LengthException::class,
+                $e,
+                sprintf(
+                    '%1$s::fromMessage("") should throw %2$s',
+                    Header::class,
+                    LengthException::class
+                )
+            );
+        }
+    }
+}

tests/Packet/MessageTest.php

@@ -0,0 +1,41 @@
+<?php
+declare(strict_types=1);
+
+namespace Tests\ArrayAccess\DnsRecord\Packet;
+
+use ArrayAccess\DnsRecord\Packet\Message;
+use PHPUnit\Framework\TestCase;
+use function md5;
+use function microtime;
+use function sprintf;
+
+class MessageTest extends TestCase
+{
+    public function testToString()
+    {
+        $message = md5(microtime());
+        $this->assertSame(
+            (string) new Message($message),
+            $message,
+            sprintf(
+                '%s->__tostring() should identical "%2$s"',
+                Message::class,
+                $message
+            )
+        );
+    }
+
+    public function testGetMessage()
+    {
+        $message = md5(microtime());
+        $this->assertSame(
+            (new Message($message))->getMessage(),
+            $message,
+            sprintf(
+                '%s->getMessage() should identical "%2$s"',
+                Message::class,
+                $message
+            )
+        );
+    }
+}

tests/Utils/BufferTest.php

@@ -0,0 +1,213 @@
+<?php
+declare(strict_types=1);
+
+namespace Tests\ArrayAccess\DnsRecord\Utils;
+
+use ArrayAccess\DnsRecord\Packet\Header;
+use ArrayAccess\DnsRecord\Packet\Question;
+use ArrayAccess\DnsRecord\Utils\Buffer;
+use ArrayAccess\DnsRecord\Utils\Lookup;
+use PHPUnit\Framework\TestCase;
+use function sprintf;
+use function strlen;
+
+class BufferTest extends TestCase
+{
+
+    public function testRead()
+    {
+        $printed = 'printed';
+        $skipped = '_skipped';
+        $buffer = $printed.$skipped;
+        $readLength = 7;
+        $offset = 0;
+        $read = Buffer::read($buffer, $offset, $readLength);
+        $this->assertSame(
+            $printed,
+            $read,
+            sprintf(
+                '%s::read("%2$s", $offset, 7) should return "%3$s"',
+                Buffer::class,
+                $buffer,
+                $printed
+            )
+        );
+        $this->assertSame(
+            $readLength,
+            $offset,
+            sprintf(
+                'Offset from %s::read("%2$s", $offset, 7) should %3$d',
+                Buffer::class,
+                $buffer,
+                $readLength
+            )
+        );
+        // offset maximum should strlen($buffer)
+        $read = Buffer::read($buffer, $offset, 1000);
+        $this->assertSame(
+            $skipped,
+            $read,
+            sprintf(
+                '%s::read("%2$s", $offset, 1000) should return "%3$s"',
+                Buffer::class,
+                $buffer,
+                $skipped
+            )
+        );
+        $this->assertSame(
+            strlen($buffer),
+            $offset,
+            sprintf(
+                'Offset from %s::read("%2$s", $offset, 1000) should %3$d',
+                Buffer::class,
+                $buffer,
+                strlen($buffer)
+            )
+        );
+    }
+
+    public function testCreateHeaderMessage()
+    {
+        $header = Header::createQueryHeader();
+        $this->assertSame(
+            $header->getMessage(),
+            Buffer::createHeaderMessage($header),
+            sprintf(
+                '%1$s::createHeaderMessage($header) should identical with $header->getMessage()',
+                Buffer::class
+            )
+        );
+    }
+
+    public function testCompressLabel()
+    {
+        $domain = 'example.com';
+        $label = Buffer::compressLabel($domain);
+        $this->assertNotSame(
+            $domain,
+            $label,
+            sprintf(
+                '%1$s::compressLabel("%2$s") should not identical with "%2$s"',
+                Buffer::class,
+                $domain
+            )
+        );
+    }
+
+    public function testReadLabel()
+    {
+        $offset = 0;
+        $domain = 'example.com';
+        $label = Buffer::compressLabel($domain);
+        $read = Buffer::readLabel($label, $offset);
+        $this->assertGreaterThan(
+            0,
+            $offset,
+            sprintf(
+                'Offset from %1$s::readLabel($label, $offset) should greater than 0',
+                Buffer::class
+            )
+        );
+        $this->assertNotSame(
+            $label,
+            $read,
+            sprintf(
+                '%1$s::readLabel($label, $offset) should not identical with $label',
+                Buffer::class
+            )
+        );
+        $this->assertSame(
+            $domain,
+            $read,
+            sprintf(
+                '%1$s::readLabel($label, $offset) should identical with $label',
+                Buffer::class
+            )
+        );
+        $this->assertEmpty(
+            Buffer::readLabel($label, $offset),
+            sprintf(
+                'With next offset of %1$s::readLabel($label, $offset) should empty',
+                Buffer::class
+            )
+        );
+        $underscore = 'example_com'; // underscore separator
+        // fallback offset
+        $offset = 0;
+        $read = Buffer::readLabel($label, $offset, '_');
+        $this->assertGreaterThan(
+            0,
+            $offset,
+            sprintf(
+                'Offset from %1$s::readLabel($label, $offset, "_") should greater than 0',
+                Buffer::class
+            )
+        );
+        $this->assertNotSame(
+            $label,
+            $read,
+            sprintf(
+                '%1$s::readLabel($label, $offset, "_") should not identical with $label',
+                Buffer::class
+            )
+        );
+        $this->assertNotSame(
+            $domain,
+            $read,
+            sprintf(
+                '%1$s::readLabel($label, $offset, "_") should not identical with "%2$s"',
+                Buffer::class,
+                $domain
+            )
+        );
+        $this->assertSame(
+            $underscore,
+            $read,
+            sprintf(
+                '%1$s::readLabel($label, $offset) should identical with "%2$s"',
+                Buffer::class,
+                $underscore
+            )
+        );
+    }
+
+    public function testCompressHeader()
+    {
+        $header = Buffer::compressHeader(
+            'A',
+            'IN'
+        );
+        $this->assertGreaterThanOrEqual(
+            10,
+            strlen($header),
+            sprintf(
+                '%1$s::compressHeader("A", "IN") length should 10 or greater',
+                Buffer::class
+            )
+        );
+    }
+
+    public function testCreateQuestionMessage()
+    {
+        $question = Question::fromFilteredResponse(
+            'example.com',
+            Lookup::RR_TYPES['A'],
+            Lookup::QCLASS_IN
+        );
+        $header = Buffer::compressHeader(
+            $question->getType(),
+            $question->getClass()
+        );
+        $message = Buffer::createQuestionMessage($question);
+        // header is on the end of binary string
+        $this->assertStringEndsWith(
+            $header,
+            $message,
+            sprintf(
+                '%1$s::createQuestionMessage(%2$s) should ending with header',
+                Buffer::class,
+                Question::class,
+            )
+        );
+    }
+}