Deprecate SimpleSelector::notEmpty() and make it the inverse of isBlank()

CHANGELOG.md

@@ -58,6 +58,7 @@ QueryPath Changelog
 - Consolidate the sibling and ancestor walks behind `next()`, `prev()`, `nextAll()`, `prevAll()`, `nextUntil()`, `prevUntil()`, `parent()`, `parents()`, `parentsUntil()` and `closest()` into one helper, so a fix to one no longer has to be repeated in its mirror (issue #115). As a side effect, `parentsUntil()` no longer loops forever on an element that is not attached to the document, and `nextUntil('')` and `prevUntil('')` treat an empty selector as no selector, as the other methods already did, instead of throwing `QueryPath\CSS\ParseException`. `closest('')` returns an empty set, as in jQuery. `nextUntil()`, `prevUntil()` and `parentsUntil()` also stop at an element already collected from an earlier starting element, as `nextAll()` and `prevAll()` do, so `nextUntil()` on each of 2000 siblings falls from about 100 ms to 1 ms
 - **Behaviour change.** `prevAll()`, `prevUntil()`, `nextAll()`, `nextUntil()`, `siblings()`, `parent()` and `closest()` now return the results for a multi-element set in jQuery's order, instead of grouped by starting element (issue #117). `prevAll()` and `prevUntil()` return reverse document order, as `parents()` and `parentsUntil()` already did, and the others return document order. `qp($xml, 'c')->add('d')->prevAll()` now returns `c, b, a` rather than `b, a, c`. `next()` and `prev()` keep the order of the starting elements, as in jQuery, and the results for a single starting element are unchanged
 - **Behaviour change.** A positional pseudo-class (`:first`, `:eq()`, `:last`, ...) in the stop selector of `nextUntil()`, `prevUntil()` and `parentsUntil()` now counts across the whole document, as jQuery's does, instead of seeing each sibling or ancestor as a one-element set (issue #118). `nextUntil(':first')` used to stop at once and now walks to the end, and `nextUntil(':eq(3)')` stops at the fourth element in the document. `closest()` no longer matches a positional selector at all, as in jQuery, where `closest(':first')` used to return the element itself. `next()`, `prev()` and `parent()` still test each candidate on its own, which agrees with jQuery for a single starting element
+- Deprecate `QueryPath\CSS\SimpleSelector::notEmpty()`, which will be removed in 5.0; use `! isBlank()` instead. It could never return `true`, and is now the inverse of `isBlank()` (issue #138)
 
 # 4.2.0
 

src/CSS/SimpleSelector.php

@@ -196,17 +196,14 @@ public function isBlank(): bool
 	}
 
 	/**
+	 * The inverse of isBlank().
+	 *
 	 * @return bool
+	 * @deprecated Use ! isBlank(). This will be removed in 5.0.
 	 */
 	public function notEmpty(): bool
 	{
-		return ! empty($this->element)
-			   && ! empty($this->id)
-			   && ! empty($this->classes)
-			   && ! empty($this->combinator)
-			   && ! empty($this->attributes)
-			   && ! empty($this->pseudoClasses)
-			   && ! empty($this->pseudoElements);
+		return ! $this->isBlank();
 	}
 
 	public function __toString()

tests/QueryPath/CSS/SelectorTest.php

@@ -131,4 +131,35 @@ public function testIterator()
 		$iterator = $selector->getIterator();
 		$this->assertInstanceOf('\Iterator', $iterator);
 	}
+
+	/**
+	 * @dataProvider notEmptySelectors
+	 */
+	public function testNotEmptyIsTheInverseOfIsBlank($selector, $index, $expected)
+	{
+		$simpleSelector = $this->parse($selector)->toArray()[0][$index];
+
+		$this->assertSame($expected, $simpleSelector->notEmpty());
+		$this->assertSame(! $expected, $simpleSelector->isBlank());
+	}
+
+	public function notEmptySelectors(): array
+	{
+		return [
+			'element'                   => ['li', 0, true],
+			'ID'                        => ['#a', 0, true],
+			'class'                     => ['.a', 0, true],
+			'attribute'                 => ['[a]', 0, true],
+			'pseudo-class'              => [':first-child', 0, true],
+			'pseudo-element'            => ['::before', 0, true],
+			'every part'                => ['ns|li#a.b[c]:first-child::before', 0, true],
+			'element with a combinator' => ['ul > li', 1, true],
+			'blank with a combinator'   => ['> li', 1, false],
+		];
+	}
+
+	public function testNotEmptyOnANewSelector()
+	{
+		$this->assertFalse((new SimpleSelector())->notEmpty());
+	}
 }