Add trimDelimiter option

CHANGELOG.md

@@ -4,6 +4,7 @@ This project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.htm
 
 ## [Unreleased]
 
+ * Add `trimDelimiter` option. [#36]
 
 ## [1.1.1] (2020-10-19)
 
@@ -51,6 +52,7 @@ This project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.htm
 [1.0.0-alpha2]: https://github.com/ausi/slug-generator/compare/v1.0.0-alpha1...v1.0.0-alpha2
 [1.0.0-alpha1]: https://github.com/ausi/slug-generator/commits/v1.0.0-alpha1
 
+[#36]: https://github.com/ausi/slug-generator/issues/36
 [#23]: https://github.com/ausi/slug-generator/issues/23
 [#13]: https://github.com/ausi/slug-generator/issues/13
 [#11]: https://github.com/ausi/slug-generator/issues/11

README.md

@@ -83,6 +83,16 @@ $generator->generate('Hello World!', ['delimiter' => '_']);   // Result: hello_w
 $generator->generate('Hello World!', ['delimiter' => '%20']); // Result: hello%20world
 ```
 
+### `trimDelimiter`, default `true`
+
+If set to `true` the delimiter will be stripped
+from the beginning and the end of the slug.
+
+```php
+$generator->generate('Hello World!');                             // Result: hello-world
+$generator->generate('Hello World!', ['trimDelimiter' => false]); // Result: hello-world-
+```
+
 ### `validChars`, default `"a-z0-9"`
 
 Valid characters that are allowed in the slug.

src/SlugGenerator.php

@@ -74,7 +74,7 @@ public function generate(string $text, iterable $options = []): string
 		$options = $this->options->merge($options);
 
 		if ($options->getValidChars() === '') {
-			return '';
+			return $options->getTrimDelimiter() || $text === '' ? '' : $options->getDelimiter();
 		}
 
 		/** @var string $text */
@@ -83,7 +83,12 @@ public function generate(string $text, iterable $options = []): string
 		$text = $this->transform($text, $options->getValidChars(), $options->getTransforms(), $options->getLocale());
 		$text = $this->removeIgnored($text, $options->getIgnoreChars());
 
-		return $this->replaceWithDelimiter($text, $options->getValidChars(), $options->getDelimiter());
+		return $this->replaceWithDelimiter(
+			$text,
+			$options->getValidChars(),
+			$options->getDelimiter(),
+			$options->getTrimDelimiter()
+		);
 	}
 
 	/**
@@ -108,7 +113,7 @@ private function removeIgnored(string $text, string $ignore): string
 	 * Replace all invalid characters with a delimiter
 	 * and strip the delimiter from the beginning and the end.
 	 */
-	private function replaceWithDelimiter(string $text, string $valid, string $delimiter): string
+	private function replaceWithDelimiter(string $text, string $valid, string $delimiter, bool $trimDelimiter): string
 	{
 		$quoted = preg_quote($delimiter);
 
@@ -123,6 +128,10 @@ private function replaceWithDelimiter(string $text, string $valid, string $delim
 			throw new \RuntimeException(sprintf('Failed to replace "%s" with "%s" in "%s".', '(?:[^'.$valid.']|'.$quoted.')+', $delimiter, $text));
 		}
 
+		if (!$trimDelimiter) {
+			return $replaced;
+		}
+
 		// Remove delimiters from the beginning and the end
 		$removed = preg_replace('(^(?:'.$quoted.')+|(?:'.$quoted.')+$)us', '', $replaced);
 

src/SlugOptions.php

@@ -27,6 +27,11 @@ class SlugOptions implements \IteratorAggregate
 	 */
 	private $delimiter = '-';
 
+	/**
+	 * @var bool
+	 */
+	private $trimDelimiter = true;
+
 	/**
 	 * @var string
 	 */
@@ -126,6 +131,24 @@ public function getDelimiter(): string
 		return $this->delimiter;
 	}
 
+	/**
+	 * @param bool $trimDelimiter True if the delimiter should be trimmed from the beginning and end of the slug
+	 *
+	 * @return static
+	 */
+	public function setTrimDelimiter(bool $trimDelimiter): self
+	{
+		$this->trimDelimiter = $trimDelimiter;
+		$this->setOptions['trimDelimiter'] = null;
+
+		return $this;
+	}
+
+	public function getTrimDelimiter(): bool
+	{
+		return $this->trimDelimiter;
+	}
+
 	/**
 	 * @param string $chars Character range for allowed characters
 	 *                      in the form of a regular expression character set,
@@ -294,6 +317,7 @@ private function assertOptionName(string $option): void
 	{
 		static $validOptions = [
 			'delimiter',
+			'trimDelimiter',
 			'validChars',
 			'ignoreChars',
 			'locale',

tests/SlugGeneratorTest.php

@@ -241,6 +241,21 @@ public function getGenerate(): array
 				'',
 				['validChars' => ''],
 			],
+			[
+				'-A B C-',
+				'-',
+				['validChars' => '-', 'trimDelimiter' => false],
+			],
+			[
+				'-A B C-',
+				'-a-b-c-',
+				['validChars' => 'a-z', 'trimDelimiter' => false],
+			],
+			[
+				'- -A B C- -',
+				'...a...b...c...',
+				['validChars' => 'a-z', 'delimiter' => '...', 'trimDelimiter' => false],
+			],
 			[
 				'contextöcontextöcontext',
 				'CONTEXTöCONTEXTöCONTEXT',

tests/SlugOptionsTest.php

@@ -35,11 +35,13 @@ public function testMerge(): void
 		$this->assertSame('x', $options->getDelimiter());
 		$this->assertSame('a-z0-9', $options->getValidChars());
 
-		$options2 = $options->merge(new SlugOptions(['validChars' => 'x']));
+		$options2 = $options->merge(new SlugOptions(['validChars' => 'x', 'trimDelimiter' => false]));
 		$this->assertSame('x', $options->getDelimiter());
 		$this->assertSame('a-z0-9', $options->getValidChars());
+		$this->assertTrue($options->getTrimDelimiter());
 		$this->assertSame('x', $options2->getDelimiter());
 		$this->assertSame('x', $options2->getValidChars());
+		$this->assertFalse($options2->getTrimDelimiter());
 	}
 
 	public function testGetIterator(): void
@@ -69,6 +71,16 @@ public function testSetDelimiter(): void
 		$this->assertSame('xx', $options->setDelimiter('xx')->getDelimiter());
 	}
 
+	public function testSetTrimDelimiter(): void
+	{
+		$options = new SlugOptions;
+		$this->assertTrue($options->getTrimDelimiter());
+
+		$options = new SlugOptions(['trimDelimiter' => false]);
+		$this->assertFalse($options->getTrimDelimiter());
+		$this->assertTrue($options->setTrimDelimiter(true)->getTrimDelimiter());
+	}
+
 	public function testSetValidChars(): void
 	{
 		$options = new SlugOptions;