feat(css_parser): CSS Parser pseudo element selector #268 (#839)

crates/biome_css_parser/src/lexer/mod.rs

@@ -762,6 +762,8 @@ impl<'src> CssLexer<'src> {
             b"nth-last-of-type" => NTHLASTOFTYPE_KW,
             b"nth-col" => NTHCOL_KW,
             b"nth-last-col" => NTHLASTCOL_KW,
+            b"ltr" => LTR_KW,
+            b"rtl" => RTL_KW,
             _ => IDENT,
         }
     }

crates/biome_css_parser/src/syntax/selector/pseudo_class/function_identifier.rs

@@ -1,16 +1,16 @@
 use crate::parser::CssParser;
-use crate::syntax::parse_error::expected_identifier;
 use crate::syntax::parse_regular_identifier;
-use crate::syntax::selector::parse_selector_function_close_token;
+use crate::syntax::selector::SELECTOR_FUNCTION_RECOVERY_SET;
 use biome_css_syntax::CssSyntaxKind::CSS_PSEUDO_CLASS_FUNCTION_IDENTIFIER;
 use biome_css_syntax::CssSyntaxKind::*;
-use biome_css_syntax::{CssSyntaxKind, T};
+use biome_css_syntax::{CssSyntaxKind, TextRange, T};
+use biome_parser::diagnostic::{expected_any, ParseDiagnostic};
+use biome_parser::parse_recovery::ParseRecovery;
 use biome_parser::parsed_syntax::ParsedSyntax;
 use biome_parser::parsed_syntax::ParsedSyntax::{Absent, Present};
 use biome_parser::{token_set, Parser, TokenSet};
 
 const PSEUDO_CLASS_FUNCTION_IDENTIFIER_SET: TokenSet<CssSyntaxKind> = token_set![DIR_KW];
-
 #[inline]
 pub(crate) fn is_at_pseudo_class_function_identifier(p: &mut CssParser) -> bool {
     p.at_ts(PSEUDO_CLASS_FUNCTION_IDENTIFIER_SET) && p.nth_at(1, T!['('])
@@ -24,10 +24,74 @@ pub(crate) fn parse_pseudo_class_function_identifier(p: &mut CssParser) -> Parse
 
     let m = p.start();
 
-    parse_regular_identifier(p).or_add_diagnostic(p, expected_identifier);
+    // we don't need to check if the identifier is valid, because we already did that
+    parse_regular_identifier(p).ok();
     p.bump(T!['(']);
-    parse_regular_identifier(p).or_add_diagnostic(p, expected_identifier);
-    parse_selector_function_close_token(p);
 
-    Present(m.complete(p, CSS_PSEUDO_CLASS_FUNCTION_IDENTIFIER))
+    let kind = if is_at_dir_parameter_identifier(p) {
+        let identifier = parse_regular_identifier(p);
+
+        if eat_or_recover_function_close_token(p, identifier) {
+            CSS_PSEUDO_CLASS_FUNCTION_IDENTIFIER
+        } else {
+            CSS_BOGUS_PSEUDO_CLASS
+        }
+    } else {
+        recover_invalid_dir_parameter_identifier(p);
+        p.expect(T![')']);
+        CSS_BOGUS_PSEUDO_CLASS
+    };
+
+    Present(m.complete(p, kind))
+}
+
+#[inline]
+fn eat_or_recover_function_close_token(p: &mut CssParser, identifier: ParsedSyntax) -> bool {
+    if p.eat(T![')']) {
+        true
+    } else {
+        let start = identifier
+            .ok()
+            .map(|m| m.range(p).start())
+            .unwrap_or_else(|| p.cur_range().start());
+
+        if let Ok(marker) = ParseRecovery::new(CSS_BOGUS, SELECTOR_FUNCTION_RECOVERY_SET).recover(p)
+        {
+            p.error(expected_dir_parameter_identifier(
+                p,
+                TextRange::new(start, marker.range(p).end()),
+            ));
+        }
+
+        p.expect(T![')']);
+
+        false
+    }
+}
+const DIR_PARAMETER_IDENTIFIER_SET: TokenSet<CssSyntaxKind> = token_set![LTR_KW, RTL_KW];
+#[inline]
+fn is_at_dir_parameter_identifier(p: &mut CssParser) -> bool {
+    p.at_ts(DIR_PARAMETER_IDENTIFIER_SET)
+}
+
+#[inline]
+fn recover_invalid_dir_parameter_identifier(p: &mut CssParser) {
+    let start = p.cur_range().start();
+
+    match ParseRecovery::new(CSS_BOGUS, SELECTOR_FUNCTION_RECOVERY_SET).recover(p) {
+        Ok(marker) => {
+            p.error(expected_dir_parameter_identifier(
+                p,
+                TextRange::new(start, marker.range(p).end()),
+            ));
+        }
+        Err(_) => {
+            p.error(expected_dir_parameter_identifier(p, p.cur_range()));
+        }
+    }
+}
+
+#[inline]
+fn expected_dir_parameter_identifier(p: &CssParser, range: TextRange) -> ParseDiagnostic {
+    expected_any(&["ltr", "rtl"], range, p)
 }

crates/biome_css_parser/tests/css_test_suite/error/selector/pseudo_class/pseudo_class_function_identifier.css

@@ -0,0 +1,11 @@
+:dir( {}
+:dir() {}
+:dir(ltr {}
+:dir(invalid {}
+:dir(.invalid) {}
+:dir(.invalid {}
+:dir(ltr .class {}
+:dir(ltr .class) {}
+:dir(invalid .class {}
+:dir(invalid .class) {}
+:dir(.invalid