diff --git a/src/Differ.php b/src/Differ.php
index d16d183..0566b2d 100644
--- a/src/Differ.php
+++ b/src/Differ.php
@@ -12,9 +12,6 @@
 use SebastianBergmann\Diff\Output\DiffOutputBuilderInterface;
 use SebastianBergmann\Diff\Output\UnifiedDiffOutputBuilder;
 
-/**
- * Diff implementation.
- */
 final class Differ
 {
     public const OLD                     = 0;
diff --git a/tests/ChunkTest.php b/tests/ChunkTest.php
index dd0485e..453603b 100644
--- a/tests/ChunkTest.php
+++ b/tests/ChunkTest.php
@@ -12,9 +12,9 @@
 use PHPUnit\Framework\TestCase;
 
 /**
- * @covers SebastianBergmann\Diff\Chunk
+ * @covers \SebastianBergmann\Diff\Chunk
  *
- * @uses SebastianBergmann\Diff\Line
+ * @uses \SebastianBergmann\Diff\Line
  */
 final class ChunkTest extends TestCase
 {
diff --git a/tests/DiffTest.php b/tests/DiffTest.php
index 1dea2b2..67ae039 100644
--- a/tests/DiffTest.php
+++ b/tests/DiffTest.php
@@ -12,9 +12,9 @@
 use PHPUnit\Framework\TestCase;
 
 /**
- * @covers SebastianBergmann\Diff\Diff
+ * @covers \SebastianBergmann\Diff\Diff
  *
- * @uses SebastianBergmann\Diff\Chunk
+ * @uses \SebastianBergmann\Diff\Chunk
  */
 final class DiffTest extends TestCase
 {
diff --git a/tests/DifferTest.php b/tests/DifferTest.php
index 8844cbd..ef5e11b 100644
--- a/tests/DifferTest.php
+++ b/tests/DifferTest.php
@@ -12,12 +12,12 @@
 use PHPUnit\Framework\TestCase;
 
 /**
- * @covers SebastianBergmann\Diff\Differ
- * @covers SebastianBergmann\Diff\Output\UnifiedDiffOutputBuilder
+ * @covers \SebastianBergmann\Diff\Differ
+ * @covers \SebastianBergmann\Diff\Output\UnifiedDiffOutputBuilder
  *
- * @uses SebastianBergmann\Diff\MemoryEfficientLongestCommonSubsequenceCalculator
- * @uses SebastianBergmann\Diff\TimeEfficientLongestCommonSubsequenceCalculator
- * @uses SebastianBergmann\Diff\Output\AbstractChunkOutputBuilder
+ * @uses \SebastianBergmann\Diff\MemoryEfficientLongestCommonSubsequenceCalculator
+ * @uses \SebastianBergmann\Diff\TimeEfficientLongestCommonSubsequenceCalculator
+ * @uses \SebastianBergmann\Diff\Output\AbstractChunkOutputBuilder
  */
 final class DifferTest extends TestCase
 {
diff --git a/tests/Exception/ConfigurationExceptionTest.php b/tests/Exception/ConfigurationExceptionTest.php
index 92b2e34..fc2aba1 100644
--- a/tests/Exception/ConfigurationExceptionTest.php
+++ b/tests/Exception/ConfigurationExceptionTest.php
@@ -12,7 +12,7 @@
 use PHPUnit\Framework\TestCase;
 
 /**
- * @covers SebastianBergmann\Diff\ConfigurationException
+ * @covers \SebastianBergmann\Diff\ConfigurationException
  */
 final class ConfigurationExceptionTest extends TestCase
 {
diff --git a/tests/Exception/InvalidArgumentExceptionTest.php b/tests/Exception/InvalidArgumentExceptionTest.php
index f2f4dfe..20f9945 100644
--- a/tests/Exception/InvalidArgumentExceptionTest.php
+++ b/tests/Exception/InvalidArgumentExceptionTest.php
@@ -12,7 +12,7 @@
 use PHPUnit\Framework\TestCase;
 
 /**
- * @covers SebastianBergmann\Diff\InvalidArgumentException
+ * @covers \SebastianBergmann\Diff\InvalidArgumentException
  */
 final class InvalidArgumentExceptionTest extends TestCase
 {
diff --git a/tests/LineTest.php b/tests/LineTest.php
index 12231bc..20a398c 100644
--- a/tests/LineTest.php
+++ b/tests/LineTest.php
@@ -12,7 +12,7 @@
 use PHPUnit\Framework\TestCase;
 
 /**
- * @covers SebastianBergmann\Diff\Line
+ * @covers \SebastianBergmann\Diff\Line
  */
 final class LineTest extends TestCase
 {
diff --git a/tests/MemoryEfficientImplementationTest.php b/tests/MemoryEfficientImplementationTest.php
index 3d980ca..6350042 100644
--- a/tests/MemoryEfficientImplementationTest.php
+++ b/tests/MemoryEfficientImplementationTest.php
@@ -10,7 +10,7 @@
 namespace SebastianBergmann\Diff;
 
 /**
- * @covers SebastianBergmann\Diff\MemoryEfficientLongestCommonSubsequenceCalculator
+ * @covers \SebastianBergmann\Diff\MemoryEfficientLongestCommonSubsequenceCalculator
  */
 final class MemoryEfficientImplementationTest extends LongestCommonSubsequenceTest
 {
diff --git a/tests/Output/AbstractChunkOutputBuilderTest.php b/tests/Output/AbstractChunkOutputBuilderTest.php
index ee51701..b20f981 100644
--- a/tests/Output/AbstractChunkOutputBuilderTest.php
+++ b/tests/Output/AbstractChunkOutputBuilderTest.php
@@ -13,11 +13,11 @@
 use SebastianBergmann\Diff\Differ;
 
 /**
- * @covers SebastianBergmann\Diff\Output\AbstractChunkOutputBuilder
+ * @covers \SebastianBergmann\Diff\Output\AbstractChunkOutputBuilder
  *
- * @uses SebastianBergmann\Diff\Differ
- * @uses SebastianBergmann\Diff\Output\UnifiedDiffOutputBuilder
- * @uses SebastianBergmann\Diff\TimeEfficientLongestCommonSubsequenceCalculator
+ * @uses \SebastianBergmann\Diff\Differ
+ * @uses \SebastianBergmann\Diff\Output\UnifiedDiffOutputBuilder
+ * @uses \SebastianBergmann\Diff\TimeEfficientLongestCommonSubsequenceCalculator
  */
 final class AbstractChunkOutputBuilderTest extends TestCase
 {
diff --git a/tests/Output/DiffOnlyOutputBuilderTest.php b/tests/Output/DiffOnlyOutputBuilderTest.php
index 720bb7e..22e079a 100644
--- a/tests/Output/DiffOnlyOutputBuilderTest.php
+++ b/tests/Output/DiffOnlyOutputBuilderTest.php
@@ -13,10 +13,10 @@
 use SebastianBergmann\Diff\Differ;
 
 /**
- * @covers SebastianBergmann\Diff\Output\DiffOnlyOutputBuilder
+ * @covers \SebastianBergmann\Diff\Output\DiffOnlyOutputBuilder
  *
- * @uses SebastianBergmann\Diff\Differ
- * @uses SebastianBergmann\Diff\TimeEfficientLongestCommonSubsequenceCalculator
+ * @uses \SebastianBergmann\Diff\Differ
+ * @uses \SebastianBergmann\Diff\TimeEfficientLongestCommonSubsequenceCalculator
  */
 final class DiffOnlyOutputBuilderTest extends TestCase
 {
diff --git a/tests/Output/Integration/StrictUnifiedDiffOutputBuilderIntegrationTest.php b/tests/Output/Integration/StrictUnifiedDiffOutputBuilderIntegrationTest.php
index d3c0736..7afabb8 100644
--- a/tests/Output/Integration/StrictUnifiedDiffOutputBuilderIntegrationTest.php
+++ b/tests/Output/Integration/StrictUnifiedDiffOutputBuilderIntegrationTest.php
@@ -16,11 +16,11 @@
 use Symfony\Component\Process\Process;
 
 /**
- * @covers SebastianBergmann\Diff\Output\StrictUnifiedDiffOutputBuilder
+ * @covers \SebastianBergmann\Diff\Output\StrictUnifiedDiffOutputBuilder
  *
- * @uses SebastianBergmann\Diff\Differ
- * @uses SebastianBergmann\Diff\TimeEfficientLongestCommonSubsequenceCalculator
- * @uses SebastianBergmann\Diff\MemoryEfficientLongestCommonSubsequenceCalculator
+ * @uses \SebastianBergmann\Diff\Differ
+ * @uses \SebastianBergmann\Diff\TimeEfficientLongestCommonSubsequenceCalculator
+ * @uses \SebastianBergmann\Diff\MemoryEfficientLongestCommonSubsequenceCalculator
  *
  * @requires OS Linux
  */
diff --git a/tests/Output/Integration/UnifiedDiffOutputBuilderIntegrationTest.php b/tests/Output/Integration/UnifiedDiffOutputBuilderIntegrationTest.php
index 60d20e6..5d3fdcf 100644
--- a/tests/Output/Integration/UnifiedDiffOutputBuilderIntegrationTest.php
+++ b/tests/Output/Integration/UnifiedDiffOutputBuilderIntegrationTest.php
@@ -14,10 +14,10 @@
 use Symfony\Component\Process\Process;
 
 /**
- * @covers SebastianBergmann\Diff\Output\UnifiedDiffOutputBuilder
+ * @covers \SebastianBergmann\Diff\Output\UnifiedDiffOutputBuilder
  *
- * @uses SebastianBergmann\Diff\Differ
- * @uses SebastianBergmann\Diff\TimeEfficientLongestCommonSubsequenceCalculator
+ * @uses \SebastianBergmann\Diff\Differ
+ * @uses \SebastianBergmann\Diff\TimeEfficientLongestCommonSubsequenceCalculator
  *
  * @requires OS Linux
  */
diff --git a/tests/Output/StrictUnifiedDiffOutputBuilderTest.php b/tests/Output/StrictUnifiedDiffOutputBuilderTest.php
index 627dc14..edd6528 100644
--- a/tests/Output/StrictUnifiedDiffOutputBuilderTest.php
+++ b/tests/Output/StrictUnifiedDiffOutputBuilderTest.php
@@ -15,11 +15,11 @@
 use SebastianBergmann\Diff\Utils\UnifiedDiffAssertTrait;
 
 /**
- * @covers SebastianBergmann\Diff\Output\StrictUnifiedDiffOutputBuilder
+ * @covers \SebastianBergmann\Diff\Output\StrictUnifiedDiffOutputBuilder
  *
- * @uses SebastianBergmann\Diff\Differ
- * @uses SebastianBergmann\Diff\TimeEfficientLongestCommonSubsequenceCalculator
- * @uses SebastianBergmann\Diff\ConfigurationException
+ * @uses \SebastianBergmann\Diff\Differ
+ * @uses \SebastianBergmann\Diff\TimeEfficientLongestCommonSubsequenceCalculator
+ * @uses \SebastianBergmann\Diff\ConfigurationException
  */
 final class StrictUnifiedDiffOutputBuilderTest extends TestCase
 {
diff --git a/tests/Output/UnifiedDiffOutputBuilderTest.php b/tests/Output/UnifiedDiffOutputBuilderTest.php
index 2861411..4b28681 100644
--- a/tests/Output/UnifiedDiffOutputBuilderTest.php
+++ b/tests/Output/UnifiedDiffOutputBuilderTest.php
@@ -13,11 +13,11 @@
 use SebastianBergmann\Diff\Differ;
 
 /**
- * @covers SebastianBergmann\Diff\Output\UnifiedDiffOutputBuilder
+ * @covers \SebastianBergmann\Diff\Output\UnifiedDiffOutputBuilder
  *
- * @uses SebastianBergmann\Diff\Differ
- * @uses SebastianBergmann\Diff\Output\AbstractChunkOutputBuilder
- * @uses SebastianBergmann\Diff\TimeEfficientLongestCommonSubsequenceCalculator
+ * @uses \SebastianBergmann\Diff\Differ
+ * @uses \SebastianBergmann\Diff\Output\AbstractChunkOutputBuilder
+ * @uses \SebastianBergmann\Diff\TimeEfficientLongestCommonSubsequenceCalculator
  */
 final class UnifiedDiffOutputBuilderTest extends TestCase
 {
@@ -65,13 +65,9 @@ public function headerProvider(): array
     }
 
     /**
-     * @param string $expected
-     * @param string $from
-     * @param string $to
-     *
      * @dataProvider provideDiffWithLineNumbers
      */
-    public function testDiffWithLineNumbers($expected, $from, $to): void
+    public function testDiffWithLineNumbers(string $expected, string $from, string $to): void
     {
         $differ = new Differ(new UnifiedDiffOutputBuilder("--- Original\n+++ New\n", true));
         $this->assertSame($expected, $differ->diff($from, $to));
@@ -88,7 +84,9 @@ public function provideDiffWithLineNumbers(): array
     public function testEmptyDiffProducesEmptyOutput(string $from, string $to): void
     {
         $differ = new Differ(new UnifiedDiffOutputBuilder('', false));
+
         $output = $differ->diff($from, $to);
+
         $this->assertEmpty($output);
     }
 
diff --git a/tests/ParserTest.php b/tests/ParserTest.php
index 905fa7c..7c9c306 100644
--- a/tests/ParserTest.php
+++ b/tests/ParserTest.php
@@ -13,11 +13,11 @@
 use SebastianBergmann\Diff\Utils\FileUtils;
 
 /**
- * @covers SebastianBergmann\Diff\Parser
+ * @covers \SebastianBergmann\Diff\Parser
  *
- * @uses SebastianBergmann\Diff\Chunk
- * @uses SebastianBergmann\Diff\Diff
- * @uses SebastianBergmann\Diff\Line
+ * @uses \SebastianBergmann\Diff\Chunk
+ * @uses \SebastianBergmann\Diff\Diff
+ * @uses \SebastianBergmann\Diff\Line
  */
 final class ParserTest extends TestCase
 {
@@ -145,7 +145,7 @@ public function testParseDiffForMulitpleFiles(): void
     }
 
     /**
-     * @param Diff[] $expected
+     * @psalm-param list<Diff> $expected
      *
      * @dataProvider diffProvider
      */
diff --git a/tests/TimeEfficientImplementationTest.php b/tests/TimeEfficientImplementationTest.php
index 69257e7..1958cca 100644
--- a/tests/TimeEfficientImplementationTest.php
+++ b/tests/TimeEfficientImplementationTest.php
@@ -10,7 +10,7 @@
 namespace SebastianBergmann\Diff;
 
 /**
- * @covers SebastianBergmann\Diff\TimeEfficientLongestCommonSubsequenceCalculator
+ * @covers \SebastianBergmann\Diff\TimeEfficientLongestCommonSubsequenceCalculator
  */
 final class TimeEfficientImplementationTest extends LongestCommonSubsequenceTest
 {
diff --git a/tests/Utils/UnifiedDiffAssertTraitTest.php b/tests/Utils/UnifiedDiffAssertTraitTest.php
index 4938146..76be549 100644
--- a/tests/Utils/UnifiedDiffAssertTraitTest.php
+++ b/tests/Utils/UnifiedDiffAssertTraitTest.php
@@ -12,7 +12,7 @@
 use PHPUnit\Framework\TestCase;
 
 /**
- * @covers SebastianBergmann\Diff\Utils\UnifiedDiffAssertTrait
+ * @covers \SebastianBergmann\Diff\Utils\UnifiedDiffAssertTrait
  */
 final class UnifiedDiffAssertTraitTest extends TestCase
 {