Add a test covering the DialectKeywords implementation

Code coverage does not count code executed in data providers as being
covered.

Author: stof

tests/Keywords/DialectKeywordsTest.php

@@ -0,0 +1,73 @@
+<?php
+
+/*
+ * This file is part of the Behat Gherkin Parser.
+ * (c) Konstantin Kudryashov <ever.zet@gmail.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Tests\Behat\Gherkin\Keywords;
+
+use Behat\Gherkin\Dialect\CucumberDialectProvider;
+use Behat\Gherkin\Keywords\DialectKeywords;
+use Behat\Gherkin\Keywords\KeywordsInterface;
+use Behat\Gherkin\Node\StepNode;
+use Tests\Behat\Gherkin\Filesystem;
+
+class DialectKeywordsTest extends KeywordsTestCase
+{
+    public function testFailsForEmptyLanguage(): void
+    {
+        $keywords = new DialectKeywords(new CucumberDialectProvider());
+
+        $this->expectException(\LogicException::class);
+        $this->expectExceptionMessage('Language cannot be empty');
+
+        $keywords->setLanguage('');
+    }
+
+    protected static function getKeywords(): KeywordsInterface
+    {
+        return new DialectKeywords(new CucumberDialectProvider());
+    }
+
+    protected static function getKeywordsArray(): array
+    {
+        $data = json_decode(Filesystem::readFile(__DIR__ . '/../../resources/gherkin-languages.json'), true, flags: \JSON_THROW_ON_ERROR);
+
+        $keywordsArray = [];
+
+        foreach ($data as $lang => $dialect) {
+            $keywordsArray[$lang] = [
+                'feature' => implode('|', $dialect['feature']),
+                'background' => implode('|', $dialect['background']),
+                'scenario' => implode('|', $dialect['scenario']),
+                'scenario_outline' => implode('|', $dialect['scenarioOutline']),
+                'examples' => implode('|', $dialect['examples']),
+                'given' => implode('|', $dialect['given']),
+                'when' => implode('|', $dialect['when']),
+                'then' => implode('|', $dialect['then']),
+                'and' => implode('|', $dialect['and']),
+                'but' => implode('|', $dialect['but']),
+            ];
+        }
+
+        return $keywordsArray;
+    }
+
+    protected static function getSteps(string $keywords, string $text, int &$line, ?string $keywordType): array
+    {
+        $steps = [];
+        foreach (explode('|', $keywords) as $keyword) {
+            if ($keyword === '* ') {
+                continue;
+            }
+
+            $steps[] = new StepNode(trim($keyword), $text, [], $line++, $keywordType);
+        }
+
+        return $steps;
+    }
+}