//! CSS style sheets and style attributes. //! //! A [StyleSheet](StyleSheet) represents a `.css` file or `` element in HTML. //! A [StyleAttribute](StyleAttribute) represents an inline `style` attribute in HTML. use crate::compat::Feature; use crate::context::{DeclarationContext, PropertyHandlerContext}; use crate::css_modules::{CssModule, CssModuleExports, CssModuleReferences}; use crate::declaration::{DeclarationBlock, DeclarationHandler}; use crate::dependencies::Dependency; use crate::error::{Error, ErrorLocation, MinifyErrorKind, ParserError, PrinterError, PrinterErrorKind}; use crate::parser::TopLevelRuleParser; use crate::printer::Printer; use crate::rules::{CssRule, CssRuleList, MinifyContext}; use crate::targets::Browsers; use crate::traits::ToCss; use cssparser::{Parser, ParserInput, RuleListParser}; use parcel_sourcemap::SourceMap; use std::collections::{HashMap, HashSet}; pub use crate::parser::ParserOptions; pub use crate::printer::PrinterOptions; pub use crate::printer::PseudoClasses; /// A CSS style sheet, representing a `.css` file or inline `` element. /// /// Style sheets can be parsed from a string, constructed from scratch, /// or created using a [Bundler](super::bundler::Bundler). Then, they can be /// minified and transformed for a set of target browsers, and serialied to a string. /// /// # Example /// /// ``` /// use lightningcss::stylesheet::{ /// StyleSheet, ParserOptions, MinifyOptions, PrinterOptions /// }; /// /// // Parse a style sheet from a string. /// let mut stylesheet = StyleSheet::parse( /// r#" /// .foo { /// color: red; /// } /// /// .bar { /// color: red; /// } /// "#, /// ParserOptions::default() /// ).unwrap(); /// /// // Minify the stylesheet. /// stylesheet.minify(MinifyOptions::default()).unwrap(); /// /// // Serialize it to a string. /// let res = stylesheet.to_css(PrinterOptions::default()).unwrap(); /// assert_eq!(res.code, ".foo, .bar {\n color: red;\n}\n"); /// ``` #[derive(Debug)] #[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))] pub struct StyleSheet<'i, 'o> { /// A list of top-level rules within the style sheet. #[cfg_attr(feature = "serde", serde(borrow))] pub rules: CssRuleList<'i>, /// A list of file names for all source files included within the style sheet. /// Sources are referenced by index in the `loc` property of each rule. pub sources: Vec, /// The source map URL extracted from the original style sheet. pub(crate) source_map_urls: Vec>, #[cfg_attr(feature = "serde", serde(skip))] /// The options the style sheet was originally parsed with. options: ParserOptions<'o, 'i>, } /// Options for the `minify` function of a [StyleSheet](StyleSheet) /// or [StyleAttribute](StyleAttribute). #[derive(Default)] pub struct MinifyOptions { /// Browser targets to compile the CSS for. pub targets: Option, /// A list of known unused symbols, including CSS class names, /// ids, and `@keyframe` names. The declarations of these will be removed. pub unused_symbols: HashSet, } /// A result returned from `to_css`, including the serialize CSS /// and other metadata depending on the input options. #[derive(Debug)] pub struct ToCssResult { /// Serialized CSS code. pub code: String, /// A map of CSS module exports, if the `css_modules` option was /// enabled during parsing. pub exports: Option, /// A map of CSS module references, if the `css_modules` config /// had `dashed_idents` enabled. pub references: Option, /// A list of dependencies (e.g. `@import` or `url()`) found in /// the style sheet, if the `analyze_dependencies` option is enabled. pub dependencies: Option>, } impl<'i, 'o> StyleSheet<'i, 'o> { /// Creates a new style sheet with the given source filenames and rules. pub fn new(sources: Vec, rules: CssRuleList<'i>, options: ParserOptions<'o, 'i>) -> StyleSheet<'i, 'o> { StyleSheet { sources, source_map_urls: Vec::new(), rules, options, } } /// Parse a style sheet from a string. pub fn parse(code: &'i str, options: ParserOptions<'o, 'i>) -> Result<'i>>> { let mut input = ParserInput::new(&code); let mut parser = Parser::new(&mut input); let rule_list_parser = RuleListParser::new_for_stylesheet(&mut parser, TopLevelRuleParser::new(&options)); let mut rules = vec![]; for rule in rule_list_parser { let rule = match rule { Ok((_, CssRule::Ignored)) => continue, Ok((_, rule)) => rule, Err((e, _)) => { if options.error_recovery { options.warn(e); continue; } return Err(Error::from(e, options.filename.clone())); } }; rules.push(rule) } Ok(StyleSheet { sources: vec![options.filename.clone()], source_map_urls: vec![parser.current_source_map_url().map(|s| s.to_owned())], rules: CssRuleList(rules), options, }) } /// Returns the source map URL for the source at the given index. pub fn source_map_url(&self, source_index: usize) -> Option<&String> { self.source_map_urls.get(source_index)?.as_ref() } /// Returns the inline source map associated with the source at the given index. pub fn source_map(&self, source_index: usize) -> Option { SourceMap::from_data_url("/", self.source_map_url(source_index)?).ok() } /// Minify and transform the style sheet for the provided browser targets. pub fn minify(&mut self, options: MinifyOptions) -> Result<(), Error> { let mut context = PropertyHandlerContext::new(options.targets, &options.unused_symbols); let mut handler = DeclarationHandler::new(options.targets); let mut important_handler = DeclarationHandler::new(options.targets); // @custom-media rules may be defined after they are referenced, but may only be defined at the top level // of a stylesheet. Do a pre-scan here and create a lookup table by name. let custom_media = if self.options.custom_media && options.targets.is_some() && !Feature::CustomMediaQueries.is_compatible(options.targets.unwrap()) { let mut custom_media = HashMap::new(); for rule in &self.rules.0 { if let CssRule::CustomMedia(rule) = rule { custom_media.insert(rule.name.0.clone(), rule.clone()); } } Some(custom_media) } else { None }; let mut ctx = MinifyContext { targets: &options.targets, handler: &mut handler, important_handler: &mut important_handler, handler_context: &mut context, unused_symbols: &options.unused_symbols, custom_media, css_modules: self.options.css_modules.is_some(), }; self.rules.minify(&mut ctx, false).map_err(|e| Error { kind: e.kind, loc: Some(ErrorLocation::new( e.loc, self.sources[e.loc.source_index as usize].clone(), )), })?; Ok(()) } /// Serialize the style sheet to a CSS string. pub fn to_css(&self, options: PrinterOptions) -> Result> { // Make sure we always have capacity > 0: https://github.com/napi-rs/napi-rs/issues/1124. let mut dest = String::with_capacity(1); let mut printer = Printer::new(&mut dest, options); printer.sources = Some(&self.sources); if printer.source_map.is_some() { printer.source_maps = self.sources.iter().enumerate().map(|(i, _)| self.source_map(i)).collect(); } if let Some(config) = &self.options.css_modules { let mut references = HashMap::new(); printer.css_module = Some(CssModule::new(config, &self.sources, &mut references)); self.rules.to_css(&mut printer)?; printer.newline()?; Ok(ToCssResult { dependencies: printer.dependencies, exports: Some(std::mem::take( &mut printer.css_module.unwrap().exports_by_source_index[0], )), code: dest, references: Some(references), }) } else { self.rules.to_css(&mut printer)?; printer.newline()?; Ok(ToCssResult { dependencies: printer.dependencies, code: dest, exports: None, references: None, }) } } } /// An inline style attribute, as in HTML or SVG. /// /// Style attributes can be parsed from a string, minified and transformed /// for a set of target browsers, and serialied to a string. /// /// # Example /// /// ``` /// use lightningcss::stylesheet::{ /// StyleAttribute, ParserOptions, MinifyOptions, PrinterOptions /// }; /// /// // Parse a style sheet from a string. /// let mut style = StyleAttribute::parse( /// "color: yellow; font-family: 'Helvetica';", /// ParserOptions::default() /// ).unwrap(); /// /// // Minify the stylesheet. /// style.minify(MinifyOptions::default()); /// /// // Serialize it to a string. /// let res = style.to_css(PrinterOptions::default()).unwrap(); /// assert_eq!(res.code, "color: #ff0; font-family: Helvetica"); /// ``` pub struct StyleAttribute<'i> { /// The declarations in the style attribute. pub declarations: DeclarationBlock<'i>, sources: Vec, } impl<'i> StyleAttribute<'i> { /// Parses a style attribute from a string. pub fn parse( code: &'i str, options: ParserOptions<'_, 'i>, ) -> Result<'i>, Error<'i>>> { let mut input = ParserInput::new(&code); let mut parser = Parser::new(&mut input); Ok(StyleAttribute { declarations: DeclarationBlock::parse(&mut parser, &options).map_err(|e| Error::from(e, "".into()))?, sources: vec![options.filename], }) } /// Minify and transform the style attribute for the provided browser targets. pub fn minify(&mut self, options: MinifyOptions) { let mut context = PropertyHandlerContext::new(options.targets, &options.unused_symbols); let mut handler = DeclarationHandler::new(options.targets); let mut important_handler = DeclarationHandler::new(options.targets); context.context = DeclarationContext::StyleAttribute; self.declarations.minify(&mut handler, &mut important_handler, &mut context); } /// Serializes the style attribute to a CSS string. pub fn to_css(&self, options: PrinterOptions) -> Result { assert!( options.source_map.is_none(), "Source maps are not supported for style attributes" ); // Make sure we always have capacity > 0: https://github.com/napi-rs/napi-rs/issues/1124. let mut dest = String::with_capacity(1); let mut printer = Printer::new(&mut dest, options); printer.sources = Some(&self.sources); self.declarations.to_css(&mut printer)?; Ok(ToCssResult { dependencies: printer.dependencies, code: dest, exports: None, references: None, }) } }