Add Title function with allWords parameter set default to false. (#1477)

Add Test for function with and without allWords and return type

src/core/etl/src/Flow/ETL/Function/ScalarFunctionChain.php

@@ -492,6 +492,11 @@ public function stringStyle(ScalarFunction|string|StringStyles $style) : self
         return new StringStyle($this, $style);
     }
 
+    public function stringTitle(ScalarFunction|bool $allWords = false) : self
+    {
+        return new StringTitle($this, $allWords);
+    }
+
     public function strPad(int $length, string $pad_string = ' ', int $type = STR_PAD_RIGHT) : self
     {
         return new StrPad($this, $length, $pad_string, $type);

src/core/etl/src/Flow/ETL/Function/StringTitle.php

@@ -0,0 +1,37 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Flow\ETL\Function;
+
+use function Flow\ETL\DSL\type_string;
+use function Symfony\Component\String\u;
+use Flow\ETL\Function\ScalarFunction\TypedScalarFunction;
+use Flow\ETL\PHP\Type\Type;
+use Flow\ETL\Row;
+
+final class StringTitle extends ScalarFunctionChain implements TypedScalarFunction
+{
+    public function __construct(
+        private readonly ScalarFunction|string $string,
+        private readonly ScalarFunction|bool $allWords = false,
+    ) {
+    }
+
+    public function eval(Row $row) : mixed
+    {
+        $string = (new Parameter($this->string))->asString($row);
+        $allWords = (new Parameter($this->allWords))->asBoolean($row);
+
+        if ($string === null) {
+            return null;
+        }
+
+        return u($string)->title(allWords: $allWords)->toString();
+    }
+
+    public function returns() : Type
+    {
+        return type_string();
+    }
+}

src/core/etl/tests/Flow/ETL/Tests/Unit/Function/StringTitleTest.php

@@ -0,0 +1,44 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Flow\ETL\Tests\Unit\Function;
+
+use function Flow\ETL\DSL\row;
+use function Flow\ETL\DSL\{ref, str_entry, type_string};
+use Flow\ETL\Function\StringTitle;
+use Flow\ETL\PHP\Type\Type;
+use Flow\ETL\Tests\FlowTestCase;
+
+final class StringTitleTest extends FlowTestCase
+{
+    public function test_returns_method_returns_string_type() : void
+    {
+        $stringTitleFunction = new StringTitle('str');
+        $returnType = $stringTitleFunction->returns();
+
+        self::assertInstanceOf(Type::class, $returnType);
+
+        self::assertTrue($returnType->isEqual(type_string()));
+    }
+
+    public function test_string_title() : void
+    {
+        self::assertSame(
+            'Foo ijssel',
+            ref('str')->stringTitle()->eval(
+                row(str_entry('str', 'foo ijssel'))
+            )
+        );
+    }
+
+    public function test_string_title_allwords() : void
+    {
+        self::assertSame(
+            'Foo Ijssel',
+            ref('str')->stringTitle(allWords: true)->eval(
+                row(str_entry('str', 'foo ijssel'))
+            )
+        );
+    }
+}