feat: add :nth-col() and :nth-last-col() selectors (parcel-bundler#302)

Author: yisibl

selectors/builder.rs

@@ -305,6 +305,8 @@ where
       | Component::Scope
       | Component::NthChild(..)
       | Component::NthLastChild(..)
+      | Component::NthCol(..)
+      | Component::NthLastCol(..)
       | Component::NthOfType(..)
       | Component::NthLastOfType(..)
       | Component::FirstOfType

selectors/matching.rs

@@ -372,6 +372,8 @@ fn matches_hover_and_active_quirk<'i, Impl: SelectorImpl<'i>>(
     | Component::Empty
     | Component::NthChild(_, _)
     | Component::NthLastChild(_, _)
+    | Component::NthCol(_, _)
+    | Component::NthLastCol(_, _)
     | Component::NthOfType(_, _)
     | Component::NthLastOfType(_, _)
     | Component::FirstOfType
@@ -787,6 +789,8 @@ where
     },
     Component::NthChild(a, b) => matches_generic_nth_child(element, context, a, b, false, false, flags_setter),
     Component::NthLastChild(a, b) => matches_generic_nth_child(element, context, a, b, false, true, flags_setter),
+    Component::NthCol(a, b) => matches_generic_nth_child(element, context, a, b, false, false, flags_setter),
+    Component::NthLastCol(a, b) => matches_generic_nth_child(element, context, a, b, false, true, flags_setter),
     Component::NthOfType(a, b) => matches_generic_nth_child(element, context, a, b, true, false, flags_setter),
     Component::NthLastOfType(a, b) => matches_generic_nth_child(element, context, a, b, true, true, flags_setter),
     Component::FirstOfType => matches_generic_nth_child(element, context, 0, 1, true, false, flags_setter),

selectors/parser.rs

@@ -1107,6 +1107,8 @@ pub enum Component<'i, Impl: SelectorImpl<'i>> {
   Scope,
   NthChild(i32, i32),
   NthLastChild(i32, i32),
+  NthCol(i32, i32), // https://www.w3.org/TR/selectors-4/#the-nth-col-pseudo
+  NthLastCol(i32, i32), // https://www.w3.org/TR/selectors-4/#the-nth-last-col-pseudo
   NthOfType(i32, i32),
   NthLastOfType(i32, i32),
   FirstOfType,
@@ -1604,10 +1606,12 @@ impl<'i, Impl: SelectorImpl<'i>> ToCss for Component<'i, Impl> {
       FirstOfType => dest.write_str(":first-of-type"),
       LastOfType => dest.write_str(":last-of-type"),
       OnlyOfType => dest.write_str(":only-of-type"),
-      NthChild(a, b) | NthLastChild(a, b) | NthOfType(a, b) | NthLastOfType(a, b) => {
+      NthChild(a, b) | NthLastChild(a, b) | NthOfType(a, b) | NthLastOfType(a, b) | NthCol(a, b) | NthLastCol(a, b) => {
         match *self {
           NthChild(_, _) => dest.write_str(":nth-child(")?,
           NthLastChild(_, _) => dest.write_str(":nth-last-child(")?,
+          NthCol(_, _) => dest.write_str(":nth-col(")?,
+          NthLastCol(_, _) => dest.write_str(":nth-last-col(")?,
           NthOfType(_, _) => dest.write_str(":nth-of-type(")?,
           NthLastOfType(_, _) => dest.write_str(":nth-last-of-type(")?,
           _ => unreachable!(),
@@ -2381,8 +2385,10 @@ where
 {
   match_ignore_ascii_case! { &name,
       "nth-child" => return parse_nth_pseudo_class(parser, input, *state, Component::NthChild),
-      "nth-of-type" => return parse_nth_pseudo_class(parser, input, *state, Component::NthOfType),
       "nth-last-child" => return parse_nth_pseudo_class(parser, input, *state, Component::NthLastChild),
+      "nth-col" => return parse_nth_pseudo_class(parser, input, *state, Component::NthCol),
+      "nth-last-col" => return parse_nth_pseudo_class(parser, input, *state, Component::NthLastCol),
+      "nth-of-type" => return parse_nth_pseudo_class(parser, input, *state, Component::NthOfType),
       "nth-last-of-type" => return parse_nth_pseudo_class(parser, input, *state, Component::NthLastOfType),
       "is" if parser.parse_is_and_where() => return parse_is_or_where(parser, input, state, Component::Is),
       "where" if parser.parse_is_and_where() => return parse_is_or_where(parser, input, state, Component::Where),

src/lib.rs

@@ -5228,6 +5228,17 @@ mod tests {
 
   #[test]
   fn test_selectors() {
+    minify_test(":nth-col(2n) {width: 20px}", ":nth-col(2n){width:20px}");
+    minify_test(":nth-col(10n-1) {width: 20px}", ":nth-col(10n-1){width:20px}");
+    minify_test(":nth-col(-n+2) {width: 20px}", ":nth-col(-n+2){width:20px}");
+    minify_test(":nth-col(even) {width: 20px}", ":nth-col(2n){width:20px}");
+    minify_test(":nth-col(odd) {width: 20px}", ":nth-col(2n+1){width:20px}");
+    minify_test(":nth-last-col(2n) {width: 20px}", ":nth-last-col(2n){width:20px}");
+    minify_test(":nth-last-col(10n-1) {width: 20px}", ":nth-last-col(10n-1){width:20px}");
+    minify_test(":nth-last-col(-n+2) {width: 20px}", ":nth-last-col(-n+2){width:20px}");
+    minify_test(":nth-last-col(even) {width: 20px}", ":nth-last-col(2n){width:20px}");
+    minify_test(":nth-last-col(odd) {width: 20px}", ":nth-last-col(2n+1){width:20px}");
+
     minify_test("[foo=\"baz\"] {color:red}", "[foo=baz]{color:red}");
     minify_test("[foo=\"foo bar\"] {color:red}", "[foo=foo\\ bar]{color:red}");
     minify_test("[foo=\"foo bar baz\"] {color:red}", "[foo=\"foo bar baz\"]{color:red}");

src/selector.rs

@@ -1385,6 +1385,8 @@ pub fn is_compatible(selectors: &SelectorList<Selectors>, targets: Option<Browse
         | Component::Negation(_)
         | Component::NthChild(_, _)
         | Component::NthLastChild(_, _)
+        | Component::NthCol(_, _)
+        | Component::NthLastCol(_, _)
         | Component::NthLastOfType(_, _)
         | Component::NthOfType(_, _)
         | Component::OnlyChild