feat(css): Recover from invalid properties (#2312)

swc_css_ast:
 - Add `DeclBlockItem`.
 - Change `DeclBlock.properties` to `DeclBlock.items`.

swc_css_parser:
 - Add a way to recovered errors.

css/Cargo.toml

@@ -6,11 +6,11 @@ edition = "2018"
 license = "Apache-2.0/MIT"
 name = "swc_css"
 repository = "https://github.com/swc-project/swc.git"
-version = "0.7.0"
+version = "0.8.0"
 
 [dependencies]
-swc_css_ast = {version = "0.6.0", path = "./ast"}
-swc_css_codegen = {version = "0.5.0", path = "./codegen"}
-swc_css_parser = {version = "0.7.0", path = "./parser"}
-swc_css_utils = {version = "0.3.0", path = "./utils/"}
-swc_css_visit = {version = "0.5.0", path = "./visit"}
+swc_css_ast = {version = "0.7.0", path = "./ast"}
+swc_css_codegen = {version = "0.6.0", path = "./codegen"}
+swc_css_parser = {version = "0.8.0", path = "./parser"}
+swc_css_utils = {version = "0.4.0", path = "./utils/"}
+swc_css_visit = {version = "0.6.0", path = "./visit"}

css/ast/Cargo.toml

@@ -6,7 +6,7 @@ edition = "2018"
 license = "Apache-2.0/MIT"
 name = "swc_css_ast"
 repository = "https://github.com/swc-project/swc.git"
-version = "0.6.0"
+version = "0.7.0"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 

css/ast/src/style_rule.rs

@@ -1,4 +1,4 @@
-use crate::{ComplexSelector, Property};
+use crate::{ComplexSelector, Property, Tokens};
 use swc_common::{ast_node, Span};
 
 #[ast_node("StyleRule")]
@@ -11,5 +11,13 @@ pub struct StyleRule {
 #[ast_node("DeclBlock")]
 pub struct DeclBlock {
     pub span: Span,
-    pub properties: Vec<Property>,
+    pub items: Vec<DeclBlockItem>,
+}
+
+#[ast_node]
+pub enum DeclBlockItem {
+    #[tag("Tokens")]
+    Invalid(Tokens),
+    #[tag("Property")]
+    Property(Property),
 }

css/codegen/Cargo.toml

@@ -6,17 +6,17 @@ edition = "2018"
 license = "Apache-2.0/MIT"
 name = "swc_css_codegen"
 repository = "https://github.com/swc-project/swc.git"
-version = "0.5.0"
+version = "0.6.0"
 
 [dependencies]
 auto_impl = "0.4.1"
 bitflags = "1.3.2"
 swc_atoms = {version = "0.2.7", path = "../../atoms"}
 swc_common = {version = "0.13.0", path = "../../common"}
-swc_css_ast = {version = "0.6.0", path = "../ast/"}
+swc_css_ast = {version = "0.7.0", path = "../ast/"}
 swc_css_codegen_macros = {version = "0.2.0", path = "macros/"}
 
 [dev-dependencies]
-swc_css_parser = {version = "0.7.0", path = "../parser"}
-swc_css_visit = {version = "0.5.0", path = "../visit"}
+swc_css_parser = {version = "0.8.0", path = "../parser"}
+swc_css_visit = {version = "0.6.0", path = "../visit"}
 testing = {version = "0.14.0", path = "../../testing"}

css/codegen/src/lib.rs

@@ -320,14 +320,19 @@ where
     fn emit_decl_block(&mut self, n: &DeclBlock) -> Result {
         punct!(self, "{");
 
-        self.emit_list(
-            &n.properties,
-            ListFormat::SemiDelimited | ListFormat::MultiLine,
-        )?;
+        self.emit_list(&n.items, ListFormat::SemiDelimited | ListFormat::MultiLine)?;
 
         punct!(self, "}");
     }
 
+    #[emitter]
+    fn emit_decl_block_item(&mut self, n: &DeclBlockItem) -> Result {
+        match n {
+            DeclBlockItem::Invalid(n) => emit!(self, n),
+            DeclBlockItem::Property(n) => emit!(self, n),
+        }
+    }
+
     #[emitter]
     fn emit_property(&mut self, n: &Property) -> Result {
         emit!(self, n.name);

css/codegen/tests/fixture.rs

@@ -1,4 +1,4 @@
-use std::path::PathBuf;
+use std::{mem::take, path::PathBuf};
 use swc_common::{FileName, Span};
 use swc_css_ast::Stylesheet;
 use swc_css_codegen::{
@@ -18,8 +18,13 @@ fn parse_again(input: PathBuf) {
 
         eprintln!("==== ==== Input ==== ====\n{}\n", fm.src);
 
+        let mut errors = vec![];
         let mut stylesheet: Stylesheet =
-            parse_file(&fm, ParserConfig { parse_values: true }).unwrap();
+            parse_file(&fm, ParserConfig { parse_values: true }, &mut errors).unwrap();
+
+        for err in take(&mut errors) {
+            err.to_diagnostics(&handler).emit();
+        }
 
         let mut css_str = String::new();
         {
@@ -32,10 +37,16 @@ fn parse_again(input: PathBuf) {
         eprintln!("==== ==== Codegen ==== ====\n{}\n", css_str);
 
         let new_fm = cm.new_source_file(FileName::Anon, css_str);
-        let mut parsed: Stylesheet = parse_file(&new_fm, ParserConfig { parse_values: true })
-            .map_err(|err| {
-                err.to_diagnostics(&handler).emit();
-            })?;
+        let mut parsed: Stylesheet =
+            parse_file(&new_fm, ParserConfig { parse_values: true }, &mut errors).map_err(
+                |err| {
+                    err.to_diagnostics(&handler).emit();
+                },
+            )?;
+
+        for err in errors {
+            err.to_diagnostics(&handler).emit();
+        }
 
         stylesheet.visit_mut_with(&mut DropSpan);
         parsed.visit_mut_with(&mut DropSpan);

css/parser/Cargo.toml

@@ -6,7 +6,7 @@ edition = "2018"
 license = "Apache-2.0/MIT"
 name = "swc_css_parser"
 repository = "https://github.com/swc-project/swc.git"
-version = "0.7.0"
+version = "0.8.0"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [features]
@@ -17,11 +17,11 @@ bitflags = "1.2.1"
 lexical = "5.2.2"
 swc_atoms = {version = "0.2.7", path = "../../atoms"}
 swc_common = {version = "0.13.0", path = "../../common"}
-swc_css_ast = {version = "0.6.0", path = "../ast"}
+swc_css_ast = {version = "0.7.0", path = "../ast"}
 unicode-xid = "0.2.2"
 
 [dev-dependencies]
 serde = "1.0.127"
 serde_json = "1.0.66"
-swc_css_visit = {version = "0.5.0", path = "../visit"}
+swc_css_visit = {version = "0.6.0", path = "../visit"}
 testing = {version = "0.14.0", path = "../../testing"}

css/parser/src/lib.rs

@@ -1,7 +1,10 @@
 #![deny(unused_must_use)]
 
-use lexer::Lexer;
-use parser::{input::TokensInput, PResult, Parser, ParserConfig};
+use crate::{
+    error::Error,
+    lexer::Lexer,
+    parser::{input::TokensInput, PResult, Parser, ParserConfig},
+};
 use swc_common::{input::StringInput, BytePos, SourceFile};
 use swc_css_ast::Tokens;
 
@@ -27,39 +30,63 @@ where
 }
 
 /// Parse a given string as `T`.
+///
+/// If there are syntax errors but if it was recoverable, it will be appendend
+/// to `errors`.
 pub fn parse_str<'a, T>(
     src: &'a str,
     start_pos: BytePos,
     end_pos: BytePos,
     config: ParserConfig,
+    errors: &mut Vec<Error>,
 ) -> PResult<T>
 where
     Parser<Lexer<StringInput<'a>>>: Parse<T>,
 {
     let lexer = Lexer::new(StringInput::new(src, start_pos, end_pos));
     let mut parser = Parser::new(lexer, config);
 
-    parser.parse()
+    let res = parser.parse();
+    errors.extend(parser.take_errors());
+    res
 }
 
 /// Parse a given file as `T`.
-pub fn parse_file<'a, T>(fm: &'a SourceFile, config: ParserConfig) -> PResult<T>
+///
+/// If there are syntax errors but if it was recoverable, it will be appendend
+/// to `errors`.
+pub fn parse_file<'a, T>(
+    fm: &'a SourceFile,
+    config: ParserConfig,
+    errors: &mut Vec<Error>,
+) -> PResult<T>
 where
     Parser<Lexer<StringInput<'a>>>: Parse<T>,
 {
     let lexer = Lexer::new(StringInput::from(fm));
     let mut parser = Parser::new(lexer, config);
 
-    parser.parse()
+    let res = parser.parse();
+    errors.extend(parser.take_errors());
+    res
 }
 
 /// Parse a given file as `T`.
-pub fn parse_tokens<'a, T>(tokens: &'a Tokens, config: ParserConfig) -> PResult<T>
+///
+/// If there are syntax errors but if it was recoverable, it will be appendend
+/// to `errors`.
+pub fn parse_tokens<'a, T>(
+    tokens: &'a Tokens,
+    config: ParserConfig,
+    errors: &mut Vec<Error>,
+) -> PResult<T>
 where
     Parser<TokensInput<'a>>: Parse<T>,
 {
     let lexer = TokensInput::new(tokens);
     let mut parser = Parser::new(lexer, config);
 
-    parser.parse()
+    let res = parser.parse();
+    errors.extend(parser.take_errors());
+    res
 }

css/parser/src/parser/mod.rs

@@ -1,10 +1,9 @@
-use std::mem::take;
-
 use self::input::{Buffer, ParserInput};
 use crate::{
     error::{Error, ErrorKind},
     Parse,
 };
+use std::mem::take;
 use swc_atoms::js_word;
 use swc_common::Span;
 use swc_css_ast::*;

css/parser/src/parser/style_rule.rs

@@ -34,13 +34,29 @@ where
 
         self.input.skip_ws()?;
 
-        let properties = self.parse_properties()?;
+        let items = self.parse_decl_block_items()?;
 
         expect!(self, "}");
 
         let span = span!(self, start);
 
-        Ok(DeclBlock { span, properties })
+        Ok(DeclBlock { span, items })
+    }
+
+    fn parse_decl_block_items(&mut self) -> PResult<Vec<DeclBlockItem>> {
+        let mut items = vec![];
+
+        while is!(self, Ident) {
+            items.push(self.parse()?);
+
+            if !eat!(self, ";") {
+                break;
+            }
+
+            self.input.skip_ws()?;
+        }
+
+        Ok(items)
     }
 
     pub(crate) fn parse_properties(&mut self) -> PResult<Vec<Property>> {
@@ -140,3 +156,42 @@ where
         self.parse_properties()
     }
 }
+
+impl<I> Parse<Vec<DeclBlockItem>> for Parser<I>
+where
+    I: ParserInput,
+{
+    fn parse(&mut self) -> PResult<Vec<DeclBlockItem>> {
+        self.parse_decl_block_items()
+    }
+}
+
+impl<I> Parse<DeclBlockItem> for Parser<I>
+where
+    I: ParserInput,
+{
+    fn parse(&mut self) -> PResult<DeclBlockItem> {
+        let start = self.input.state();
+        let start_pos = self.input.cur_span()?.lo;
+
+        let prop = self.parse().map(DeclBlockItem::Property);
+
+        match prop {
+            Ok(v) => return Ok(v),
+            Err(err) => {
+                self.errors.push(err);
+            }
+        }
+
+        self.input.reset(&start);
+        let mut tokens = vec![];
+        while !is_one_of!(self, EOF, ";", "}") {
+            tokens.extend(self.input.bump()?);
+        }
+
+        Ok(DeclBlockItem::Invalid(Tokens {
+            span: span!(self, start_pos),
+            tokens,
+        }))
+    }
+}