feat(functions): Add list-remove function

src/functions/list/_index.scss

@@ -1,4 +1,5 @@
 @forward './list-contains/list-contains.scss';
 @forward './list-includes/list-includes.scss';
 @forward './list-join/list-join.scss';
+@forward './list-remove/list-remove.scss';
 @forward './list-slice/list-slice.scss';

src/functions/list/list-remove/list-remove.scss

@@ -0,0 +1,26 @@
+@use 'sass:list';
+@use 'sass:meta';
+
+/**
+ * Removes the list element by index.
+ *
+ * @param    {list}      $list          The input list.
+ * @param    {number}    $index ['']    The list element index to remove. Use negative index to remove from the end of list.
+ *
+ * @return   {list}      A list without element with specified `$index` if found, original list otherwise.
+ */
+@function list-remove($list, $index: null) {
+	$result: ();
+	$index: if(meta.type-of($index) == 'number', $index, 0);
+	$index: if($index < 0, list.length($list) + $index + 1, $index);
+	$bracketed: list.is-bracketed($list);
+	$separator: list.separator($list);
+
+	@for $i from 1 through list.length($list) {
+		@if $i != $index {
+			$result: list.append($result, list.nth($list, $i));
+		}
+	}
+
+	@return list.join((), $result, $separator, $bracketed);
+}

src/functions/list/list-remove/list-remove.test.scss

@@ -0,0 +1,41 @@
+@use 'true' as *; // sass-true
+@use './list-remove.scss' as *;
+
+@include describe('Functions') {
+	@include describe('list-remove') {
+		@include it('Removes element from list using positive index') {
+			@include assert-equal(list-remove((1, 2, 3, 4, 5), 1), (2, 3, 4, 5));
+			@include assert-equal(list-remove((1, 2, 3, 4, 5), 2), (1, 3, 4, 5));
+			@include assert-equal(list-remove((1, (2, 2), (3, 3), 4, 5), 2), (1, (3, 3), 4, 5));
+		}
+
+		@include it('Removes element from list using negative index') {
+			@include assert-equal(list-remove((1, 2, 3, 4, 5), -1), (1, 2, 3, 4));
+			@include assert-equal(list-remove((1, 2, 3, 4, 5), -2), (1, 2, 3, 5));
+			@include assert-equal(list-remove((1, (2, 2), (3, 3), 4, 5), -3), (1, (2, 2), 4, 5));
+		}
+
+		@include it('Returns original list clone if calculated $index is out of range or invalid') {
+			@include assert-equal(list-remove((1, 2, 3, 4, 5), 'string'), (1, 2, 3, 4, 5));
+			@include assert-equal(list-remove((1, 2, 3, 4, 5), null), (1, 2, 3, 4, 5));
+			@include assert-equal(list-remove((1, 2, 3, 4, 5), true), (1, 2, 3, 4, 5));
+			@include assert-equal(list-remove((1, 2, 3, 4, 5), 1.5), (1, 2, 3, 4, 5));
+			@include assert-equal(list-remove((1, 2, 3, 4, 5), 1s), (1, 2, 3, 4, 5));
+			@include assert-equal(list-remove((1, 2, 3, 4, 5), ()), (1, 2, 3, 4, 5));
+			@include assert-equal(list-remove((1, 2, 3, 4, 5), 0), (1, 2, 3, 4, 5));
+			@include assert-equal(list-remove((1, 2, 3, 4, 5), 100), (1, 2, 3, 4, 5));
+			@include assert-equal(list-remove((1, (2, 2), (3, 3), 4, 5), -100), (1, (2, 2), (3, 3), 4, 5));
+		}
+
+		@include it('Respect the list separator') {
+			@include assert-equal(list-remove((1 2 3 4 5), 2), (1 3 4 5));
+		}
+
+		@include it('Respect the list brackets') {
+			$list-input: 1, 2, 3, 4, 5;
+			$list-expected: 1, 3, 4, 5;
+
+			@include assert-equal(list-remove($list-input, 2), $list-expected);
+		}
+	}
+}