diff --git a/phpcs.xml.dist b/phpcs.xml.dist
index 6d0b4350..525aa809 100644
--- a/phpcs.xml.dist
+++ b/phpcs.xml.dist
@@ -23,6 +23,7 @@
             <property name="spacing" value="0" />
         </properties>
     </rule>
+    <rule ref="Generic.NamingConventions.CamelCapsFunctionName" />
     <rule ref="Generic.PHP.NoSilencedErrors" />
     <rule ref="Generic.Strings.UnnecessaryStringConcat">
         <properties>
diff --git a/tests/unit/Exceptions/NestedValidationExceptionTest.php b/tests/unit/Exceptions/NestedValidationExceptionTest.php
index a2337f29..5cc9480a 100644
--- a/tests/unit/Exceptions/NestedValidationExceptionTest.php
+++ b/tests/unit/Exceptions/NestedValidationExceptionTest.php
@@ -39,7 +39,7 @@ class NestedValidationExceptionTest extends TestCase
     /**
      * @test
      */
-    public function addingTheSameInstanceShouldAddJustASingleReference(): void
+    public function addingTheSameInstanceShouldAddJustOneSingleReference(): void
     {
         $composite = new AttributeException('input', 'id', [], 'trim');
         $node = new IntValException('input', 'id', [], 'trim');
diff --git a/tests/unit/Exceptions/ValidationExceptionTest.php b/tests/unit/Exceptions/ValidationExceptionTest.php
index 564c042f..d9e3b69e 100644
--- a/tests/unit/Exceptions/ValidationExceptionTest.php
+++ b/tests/unit/Exceptions/ValidationExceptionTest.php
@@ -62,7 +62,7 @@ final class ValidationExceptionTest extends TestCase
     /**
      * @test
      */
-    public function itShouldRetrieveASingleParameter(): void
+    public function itShouldRetrieveOneSingleParameter(): void
     {
         $name = 'any name';
         $value = 'any value';
@@ -85,7 +85,7 @@ final class ValidationExceptionTest extends TestCase
     /**
      * @test
      */
-    public function itShouldHaveADefaultTemplate(): void
+    public function itShouldHaveTemplateByDefault(): void
     {
         $sut = new ValidationException('input', 'id', [], 'trim');
 
diff --git a/tests/unit/FactoryTest.php b/tests/unit/FactoryTest.php
index a207eb3b..7fd936ef 100644
--- a/tests/unit/FactoryTest.php
+++ b/tests/unit/FactoryTest.php
@@ -39,7 +39,7 @@ final class FactoryTest extends TestCase
     /**
      * @test
      */
-    public function shouldCreateARuleByNameBasedOnNamespace(): void
+    public function shouldCreateRuleByNameBasedOnNamespace(): void
     {
         $factory = new Factory([self::TEST_RULES_NAMESPACE], [], 'trim');
 
@@ -59,7 +59,7 @@ final class FactoryTest extends TestCase
     /**
      * @test
      */
-    public function shouldDefineConstructorArgumentsWhenCreatingARule(): void
+    public function shouldDefineConstructorArgumentsWhenCreatingRule(): void
     {
         $constructorArguments = [true, false, true, false];
 
diff --git a/tests/unit/Rules/AbstractCompositeTest.php b/tests/unit/Rules/AbstractCompositeTest.php
index 69c9ea50..61e347dc 100644
--- a/tests/unit/Rules/AbstractCompositeTest.php
+++ b/tests/unit/Rules/AbstractCompositeTest.php
@@ -92,7 +92,7 @@ final class AbstractCompositeTest extends TestCase
     /**
      * @test
      */
-    public function shouldNotUpdateInternalRuleAlreadyHasAName(): void
+    public function shouldNotUpdateInternalRuleWhenItAlreadyHasName(): void
     {
         $rule = $this->createMock(Validatable::class);
         $rule
@@ -140,7 +140,7 @@ final class AbstractCompositeTest extends TestCase
     /**
      * @test
      */
-    public function shouldDefineNameForInternalRulesWhenItHasNotAName(): void
+    public function shouldDefineNameForInternalRulesWhenItDoesNotHaveName(): void
     {
         $ruleName = 'something';
 
@@ -166,7 +166,7 @@ final class AbstractCompositeTest extends TestCase
     /**
      * @test
      */
-    public function shouldNotDefineNameForInternalRulesWhenItHasAName(): void
+    public function shouldNotDefineNameForInternalRulesWhenItAlreadyHasName(): void
     {
         $ruleName = 'something';
 
diff --git a/tests/unit/Rules/AbstractRelatedTest.php b/tests/unit/Rules/AbstractRelatedTest.php
index 339fcaa3..e0f26052 100644
--- a/tests/unit/Rules/AbstractRelatedTest.php
+++ b/tests/unit/Rules/AbstractRelatedTest.php
@@ -125,7 +125,7 @@ final class AbstractRelatedTest extends TestCase
     /**
      * @test
      */
-    public function shouldDefineRuleNameAsReferenceWhenRuleDoesNotHaveAName(): void
+    public function shouldDefineRuleNameAsReferenceWhenRuleDoesNotHaveName(): void
     {
         $reference = 'something';
 
@@ -150,7 +150,7 @@ final class AbstractRelatedTest extends TestCase
     /**
      * @test
      */
-    public function shouldNotDefineRuleNameAsReferenceWhenRuleDoesHaveAName(): void
+    public function shouldNotDefineRuleNameAsReferenceWhenRuleDoesHaveName(): void
     {
         $reference = 'something';
 
diff --git a/tests/unit/Rules/AlwaysInvalidTest.php b/tests/unit/Rules/AlwaysInvalidTest.php
index 77f17457..3521450f 100644
--- a/tests/unit/Rules/AlwaysInvalidTest.php
+++ b/tests/unit/Rules/AlwaysInvalidTest.php
@@ -47,7 +47,7 @@ final class AlwaysInvalidTest extends TestCase
      *
      * @dataProvider providerForInvalidInput
      */
-    public function itShouldValidateInputWhenItIsAValidAlwaysInvalid($input): void
+    public function itShouldAlwaysBeInvalid($input): void
     {
         $rule = new AlwaysInvalid();
 
diff --git a/tests/unit/Rules/AlwaysValidTest.php b/tests/unit/Rules/AlwaysValidTest.php
index 56fdcda0..28761a39 100644
--- a/tests/unit/Rules/AlwaysValidTest.php
+++ b/tests/unit/Rules/AlwaysValidTest.php
@@ -47,7 +47,7 @@ final class AlwaysValidTest extends TestCase
      *
      * @dataProvider providerForValidInput
      */
-    public function itShouldValidateInputWhenItIsAValidAlwaysValid($input): void
+    public function itAlwaysBeValid($input): void
     {
         $rule = new AlwaysValid();
 
diff --git a/tests/unit/Rules/CallbackTest.php b/tests/unit/Rules/CallbackTest.php
index 68904515..6b46e492 100644
--- a/tests/unit/Rules/CallbackTest.php
+++ b/tests/unit/Rules/CallbackTest.php
@@ -35,7 +35,7 @@ final class CallbackTest extends RuleTestCase
     {
         return [
             [new Callback('is_a', 'stdClass'), new \stdClass()],
-            [new Callback([$this, 'thisIsASampleCallbackUsedInsideThisTest']), 'test'],
+            [new Callback([$this, 'sampleCallbackUsedInsideThisTest']), 'test'],
             [new Callback('is_string'), 'test'],
             [
                 new Callback(function () {
@@ -46,7 +46,7 @@ final class CallbackTest extends RuleTestCase
         ];
     }
 
-    public function thisIsASampleCallbackUsedInsideThisTest()
+    public function sampleCallbackUsedInsideThisTest()
     {
         return true;
     }
diff --git a/tests/unit/Rules/HexRgbColorTest.php b/tests/unit/Rules/HexRgbColorTest.php
index 8bfae968..86be3872 100644
--- a/tests/unit/Rules/HexRgbColorTest.php
+++ b/tests/unit/Rules/HexRgbColorTest.php
@@ -31,7 +31,7 @@ class HexRgbColorTest extends TestCase
      *
      * @test
      */
-    public function hexRgbColorValuesONLYShouldReturnTrue($validHexRgbColor): void
+    public function hexRgbColorValuesOnlyShouldReturnTrue($validHexRgbColor): void
     {
         $validator = new HexRgbColor();
 
diff --git a/tests/unit/Rules/KeySetTest.php b/tests/unit/Rules/KeySetTest.php
index b743ecd9..cf6aca34 100644
--- a/tests/unit/Rules/KeySetTest.php
+++ b/tests/unit/Rules/KeySetTest.php
@@ -70,7 +70,7 @@ final class KeySetTest extends TestCase
      * @expectedException \Respect\Validation\Exceptions\ComponentException
      * @expectedExceptionMessage KeySet rule accepts only Key rules
      */
-    public function shouldNotAcceptAllOfWithANonKeyRule(): void
+    public function shouldNotAcceptAllOfWithNonKeyRule(): void
     {
         $alwaysValid = new AlwaysValid();
         $allOf = new AllOf($alwaysValid);
@@ -84,7 +84,7 @@ final class KeySetTest extends TestCase
      * @expectedException \Respect\Validation\Exceptions\ComponentException
      * @expectedExceptionMessage KeySet rule accepts only Key rules
      */
-    public function shouldNotAcceptANonKeyRule(): void
+    public function shouldNotAcceptNonKeyRule(): void
     {
         $alwaysValid = new AlwaysValid();
 
diff --git a/tests/unit/Rules/SfTest.php b/tests/unit/Rules/SfTest.php
index 97509750..9ba5c8ae 100644
--- a/tests/unit/Rules/SfTest.php
+++ b/tests/unit/Rules/SfTest.php
@@ -55,7 +55,7 @@ final class SfTest extends TestCase
     /**
      * @test
      */
-    public function itShouldHaveAValidatorByDefault(): void
+    public function itShouldHaveTheValidatorByDefault(): void
     {
         $sut = new Sf(new IsNull());
 
diff --git a/tests/unit/Rules/SubdivisionCodeTest.php b/tests/unit/Rules/SubdivisionCodeTest.php
index 0bb1109b..782c50f0 100644
--- a/tests/unit/Rules/SubdivisionCodeTest.php
+++ b/tests/unit/Rules/SubdivisionCodeTest.php
@@ -49,7 +49,7 @@ class SubdivisionCodeTest extends TestCase
     /**
      * @test
      */
-    public function shouldDefineASubdivisionCodeFormatOnConstructor(): void
+    public function shouldDefineSubdivisionCodeFormatOnConstructor(): void
     {
         $countryCode = 'US';
         $countrySubdivision = new SubdivisionCode($countryCode);