use std::{collections::BTreeMap, fmt::Display}; use once_cell::sync::Lazy; use rustc_hash::{FxHashMap, FxHashSet}; use swc_core::{ common::{BytePos, Span, Spanned, SyntaxContext, comments::Comments, source_map::SmallPos}, ecma::{ ast::*, atoms::{Atom, atom}, utils::{IsDirective, find_pat_ids}, visit::{Visit, VisitWith}, }, }; use turbo_rcstr::{RcStr, rcstr}; use turbo_tasks::{FxIndexMap, FxIndexSet, ResolvedVc}; use turbopack_core::{issue::IssueSource, source::Source}; use super::{JsValue, ModuleValue, top_level_await::has_top_level_await}; use crate::{ SpecifiedModuleType, analyzer::{ConstantValue, ObjectPart}, magic_identifier, tree_shake::{PartId, find_turbopack_part_id_in_asserts}, }; #[turbo_tasks::value] #[derive(Default, Debug, Clone, Hash)] pub struct ImportAnnotations { // TODO store this in more structured way #[turbo_tasks(trace_ignore)] map: BTreeMap, } /// Enables a specified transition for the annotated import static ANNOTATION_TRANSITION: Lazy = Lazy::new(|| crate::annotations::ANNOTATION_TRANSITION.into()); /// Changes the chunking type for the annotated import static ANNOTATION_CHUNKING_TYPE: Lazy = Lazy::new(|| crate::annotations::ANNOTATION_CHUNKING_TYPE.into()); /// Changes the type of the resolved module (only "json" is supported currently) static ATTRIBUTE_MODULE_TYPE: Lazy = Lazy::new(|| "type".into()); impl ImportAnnotations { pub fn parse(with: Option<&ObjectLit>) -> ImportAnnotations { let Some(with) = with else { return ImportAnnotations::default(); }; let mut map = BTreeMap::new(); // The `with` clause is way more restrictive than `ObjectLit`, it only allows // string -> value and value can only be a string. // We just ignore everything else here till the SWC ast is more restrictive. for (key, value) in with.props.iter().filter_map(|prop| { let kv = prop.as_prop()?.as_key_value()?; let Lit::Str(str) = kv.value.as_lit()? else { return None; }; Some((&kv.key, str)) }) { let key = match key { PropName::Ident(ident) => ident.sym.as_str(), PropName::Str(str) => str.value.as_str(), // the rest are invalid, ignore for now till SWC ast is correct _ => continue, }; map.insert(key.into(), value.value.as_str().into()); } ImportAnnotations { map } } pub fn parse_dynamic(with: &JsValue) -> Option { let mut map = BTreeMap::new(); let JsValue::Object { parts, .. } = with else { return None; }; for part in parts.iter() { let ObjectPart::KeyValue(key, value) = part else { continue; }; let ( JsValue::Constant(ConstantValue::Str(key)), JsValue::Constant(ConstantValue::Str(value)), ) = (key, value) else { continue; }; map.insert(key.as_str().into(), value.as_str().into()); } Some(ImportAnnotations { map }) } /// Returns the content on the transition annotation pub fn transition(&self) -> Option<&str> { self.get(&ANNOTATION_TRANSITION) } /// Returns the content on the chunking-type annotation pub fn chunking_type(&self) -> Option<&str> { self.get(&ANNOTATION_CHUNKING_TYPE) } /// Returns the content on the type attribute pub fn module_type(&self) -> Option<&str> { self.get(&ATTRIBUTE_MODULE_TYPE) } pub fn get(&self, key: &Atom) -> Option<&str> { self.map.get(key).map(|w| w.as_str()) } } impl Display for ImportAnnotations { fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result { let mut it = self.map.iter(); if let Some((k, v)) = it.next() { write!(f, "{{ {k}: {v}")? } else { return f.write_str("{}"); }; for (k, v) in it { write!(f, ", {k}: {v}")? } f.write_str(" }") } } #[derive(Debug)] pub(crate) enum Reexport { Star, Namespace { exported: Atom }, Named { imported: Atom, exported: Atom }, } /// The storage for all kinds of imports. /// /// Note that when it's initialized by calling `analyze`, it only contains ESM /// import/exports. #[derive(Default, Debug)] pub(crate) struct ImportMap { /// Map from identifier to (index in references, exported symbol) imports: FxIndexMap, /// Map from identifier to index in references namespace_imports: FxIndexMap, /// List of (index in references, imported symbol, exported symbol) reexports: Vec<(usize, Reexport)>, /// Ordered list of imported symbols references: FxIndexSet, /// True, when the module has imports has_imports: bool, /// True, when the module has exports has_exports: bool, /// True if the module is an ESM module due to top-level await. has_top_level_await: bool, /// True if the module has "use strict" pub(crate) strict: bool, /// Locations of [webpack-style "magic comments"][magic] that override import behaviors. /// /// Most commonly, these are `/* webpackIgnore: true */` comments. See [ImportAttributes] for /// full details. /// /// [magic]: https://webpack.js.org/api/module-methods/#magic-comments attributes: FxHashMap, /// The module specifiers of star imports that are accessed dynamically and should be imported /// as a whole. full_star_imports: FxHashSet, pub(crate) exports: FxHashMap, } /// Represents a collection of [webpack-style "magic comments"][magic] that override import /// behaviors. /// /// [magic]: https://webpack.js.org/api/module-methods/#magic-comments #[derive(Debug)] pub struct ImportAttributes { /// Should we ignore this import expression when bundling? If so, the import expression will be /// left as-is in Turbopack's output. /// /// This is set by using either a `webpackIgnore` or `turbopackIgnore` comment. /// /// Example: /// ```js /// const a = import(/* webpackIgnore: true */ "a"); /// const b = import(/* turbopackIgnore: true */ "b"); /// ``` pub ignore: bool, } impl ImportAttributes { pub const fn empty() -> Self { ImportAttributes { ignore: false } } pub fn empty_ref() -> &'static Self { // use `Self::empty` here as `Default::default` isn't const static DEFAULT_VALUE: ImportAttributes = ImportAttributes::empty(); &DEFAULT_VALUE } } impl Default for ImportAttributes { fn default() -> Self { ImportAttributes::empty() } } impl Default for &ImportAttributes { fn default() -> Self { ImportAttributes::empty_ref() } } #[derive(Debug, Clone, PartialEq, Eq, Hash)] pub(crate) enum ImportedSymbol { ModuleEvaluation, Symbol(Atom), Exports, Part(u32), PartEvaluation(u32), } #[derive(Debug, Clone, PartialEq, Eq, Hash)] pub(crate) struct ImportMapReference { pub module_path: Atom, pub imported_symbol: ImportedSymbol, pub annotations: ImportAnnotations, pub issue_source: Option, } impl ImportMap { pub fn is_esm(&self, specified_type: SpecifiedModuleType) -> bool { if self.has_exports { return true; } match specified_type { SpecifiedModuleType::Automatic => { self.has_exports || self.has_imports || self.has_top_level_await } SpecifiedModuleType::CommonJs => false, SpecifiedModuleType::EcmaScript => true, } } pub fn get_import(&self, id: &Id) -> Option { if let Some((i, i_sym)) = self.imports.get(id) { let r = &self.references[*i]; return Some(JsValue::member( Box::new(JsValue::Module(ModuleValue { module: r.module_path.clone(), annotations: r.annotations.clone(), })), Box::new(i_sym.clone().into()), )); } if let Some(i) = self.namespace_imports.get(id) { let r = &self.references[*i]; return Some(JsValue::Module(ModuleValue { module: r.module_path.clone(), annotations: r.annotations.clone(), })); } None } pub fn get_attributes(&self, span: Span) -> &ImportAttributes { self.attributes.get(&span.lo).unwrap_or_default() } // TODO this could return &str instead of String to avoid cloning pub fn get_binding(&self, id: &Id) -> Option<(usize, Option)> { if let Some((i, i_sym)) = self.imports.get(id) { return Some((*i, Some(i_sym.as_str().into()))); } if let Some(i) = self.namespace_imports.get(id) { return Some((*i, None)); } None } pub fn references(&self) -> impl ExactSizeIterator { self.references.iter() } pub fn reexports(&self) -> impl ExactSizeIterator { self.reexports.iter().map(|(i, r)| (*i, r)) } /// Analyze ES import pub(super) fn analyze( m: &Program, source: Option>>, comments: Option<&dyn Comments>, ) -> Self { let mut data = ImportMap::default(); // We have to analyze imports first to determine if a star import is dynamic. // We can't do this in the visitor because import may (and likely) comes before usages, and // a method invoked after visitor will not work because we need to preserve the import // order. if let Program::Module(m) = m { let mut candidates = FxIndexMap::default(); // Imports are hoisted to the top of the module. // So we have to collect all imports first. m.body.iter().for_each(|stmt| { if let ModuleItem::ModuleDecl(ModuleDecl::Import(import)) = stmt { for s in &import.specifiers { if let ImportSpecifier::Namespace(s) = s { candidates.insert(s.local.to_id(), import.src.value.clone()); } } } }); let mut analyzer = StarImportAnalyzer { candidates, full_star_imports: &mut data.full_star_imports, }; m.visit_with(&mut analyzer); } let mut analyzer = Analyzer { data: &mut data, source, comments, }; m.visit_with(&mut analyzer); data } pub(crate) fn should_import_all(&self, esm_reference_index: usize) -> bool { let r = &self.references[esm_reference_index]; self.full_star_imports.contains(&r.module_path) } } struct StarImportAnalyzer<'a> { /// The local identifiers of the star imports candidates: FxIndexMap, full_star_imports: &'a mut FxHashSet, } impl Visit for StarImportAnalyzer<'_> { fn visit_expr(&mut self, node: &Expr) { if let Expr::Ident(i) = node && let Some(module_path) = self.candidates.get(&i.to_id()) { self.full_star_imports.insert(module_path.clone()); return; } node.visit_children_with(self); } fn visit_import_decl(&mut self, _: &ImportDecl) {} fn visit_member_expr(&mut self, node: &MemberExpr) { match &node.prop { MemberProp::Ident(..) | MemberProp::PrivateName(..) => { if node.obj.is_ident() { return; } // We can skip `visit_expr(obj)` because it's not a dynamic access node.obj.visit_children_with(self); } MemberProp::Computed(..) => { node.obj.visit_with(self); node.prop.visit_with(self); } } } fn visit_pat(&mut self, pat: &Pat) { if let Pat::Ident(i) = pat && let Some(module_path) = self.candidates.get(&i.to_id()) { self.full_star_imports.insert(module_path.clone()); return; } pat.visit_children_with(self); } fn visit_simple_assign_target(&mut self, node: &SimpleAssignTarget) { if let SimpleAssignTarget::Ident(i) = node && let Some(module_path) = self.candidates.get(&i.to_id()) { self.full_star_imports.insert(module_path.clone()); return; } node.visit_children_with(self); } } struct Analyzer<'a> { data: &'a mut ImportMap, source: Option>>, comments: Option<&'a dyn Comments>, } impl Analyzer<'_> { fn ensure_reference( &mut self, span: Span, module_path: Atom, imported_symbol: ImportedSymbol, annotations: ImportAnnotations, ) -> Option { let issue_source = self .source .map(|s| IssueSource::from_swc_offsets(s, span.lo.to_u32(), span.hi.to_u32())); let r = ImportMapReference { module_path, imported_symbol, issue_source, annotations, }; if let Some(i) = self.data.references.get_index_of(&r) { Some(i) } else { let i = self.data.references.len(); self.data.references.insert(r); Some(i) } } } fn export_as_atom(name: &ModuleExportName) -> &Atom { match name { ModuleExportName::Ident(ident) => &ident.sym, ModuleExportName::Str(s) => &s.value, } } impl Visit for Analyzer<'_> { fn visit_import_decl(&mut self, import: &ImportDecl) { self.data.has_imports = true; let annotations = ImportAnnotations::parse(import.with.as_deref()); let internal_symbol = parse_with(import.with.as_deref()); if internal_symbol.is_none() { self.ensure_reference( import.span, import.src.value.clone(), ImportedSymbol::ModuleEvaluation, annotations.clone(), ); } for s in &import.specifiers { let symbol = internal_symbol .clone() .unwrap_or_else(|| get_import_symbol_from_import(s)); let i = self.ensure_reference( import.span, import.src.value.clone(), symbol, annotations.clone(), ); let i = match i { Some(v) => v, None => continue, }; let (local, orig_sym) = match s { ImportSpecifier::Named(ImportNamedSpecifier { local, imported, .. }) => match imported { Some(imported) => (local.to_id(), orig_name(imported)), _ => (local.to_id(), local.sym.clone()), }, ImportSpecifier::Default(s) => (s.local.to_id(), "default".into()), ImportSpecifier::Namespace(s) => { self.data.namespace_imports.insert(s.local.to_id(), i); continue; } }; self.data.imports.insert(local, (i, orig_sym)); } if import.specifiers.is_empty() && let Some(internal_symbol) = internal_symbol { self.ensure_reference( import.span, import.src.value.clone(), internal_symbol, annotations, ); } } fn visit_export_all(&mut self, export: &ExportAll) { self.data.has_exports = true; let annotations = ImportAnnotations::parse(export.with.as_deref()); self.ensure_reference( export.span, export.src.value.clone(), ImportedSymbol::ModuleEvaluation, annotations.clone(), ); let symbol = parse_with(export.with.as_deref()); let i = self.ensure_reference( export.span, export.src.value.clone(), symbol.unwrap_or(ImportedSymbol::Exports), annotations, ); if let Some(i) = i { self.data.reexports.push((i, Reexport::Star)); } } fn visit_named_export(&mut self, export: &NamedExport) { self.data.has_exports = true; let Some(ref src) = export.src else { export.visit_children_with(self); return; }; let annotations = ImportAnnotations::parse(export.with.as_deref()); let internal_symbol = parse_with(export.with.as_deref()); if internal_symbol.is_none() || export.specifiers.is_empty() { self.ensure_reference( export.span, src.value.clone(), ImportedSymbol::ModuleEvaluation, annotations.clone(), ); } for spec in export.specifiers.iter() { let symbol = internal_symbol .clone() .unwrap_or_else(|| get_import_symbol_from_export(spec)); let i = self.ensure_reference(export.span, src.value.clone(), symbol, annotations.clone()); let i = match i { Some(v) => v, None => continue, }; match spec { ExportSpecifier::Namespace(n) => { self.data.reexports.push(( i, Reexport::Namespace { exported: export_as_atom(&n.name).clone(), }, )); } ExportSpecifier::Default(d) => { self.data.reexports.push(( i, Reexport::Named { imported: atom!("default"), exported: d.exported.sym.clone(), }, )); } ExportSpecifier::Named(n) => { self.data.reexports.push(( i, Reexport::Named { imported: export_as_atom(&n.orig).clone(), exported: export_as_atom(n.exported.as_ref().unwrap_or(&n.orig)) .clone(), }, )); } } } } fn visit_export_decl(&mut self, n: &ExportDecl) { self.data.has_exports = true; if self.comments.is_some() { // only visit children if we potentially need to mark import / requires n.visit_children_with(self); } match &n.decl { Decl::Class(n) => { self.data .exports .insert(n.ident.sym.as_str().into(), n.ident.to_id()); } Decl::Fn(n) => { self.data .exports .insert(n.ident.sym.as_str().into(), n.ident.to_id()); } Decl::Var(..) | Decl::Using(..) => { let ids: Vec = find_pat_ids(&n.decl); for id in ids { self.data.exports.insert(id.0.as_str().into(), id); } } _ => {} } } fn visit_export_default_decl(&mut self, n: &ExportDefaultDecl) { self.data.has_exports = true; if self.comments.is_some() { // only visit children if we potentially need to mark import / requires n.visit_children_with(self); } self.data.exports.insert( rcstr!("default"), // Mirror what `EsmModuleItem::code_generation` does, these are live bindings if the // class/function has an identifier. match &n.decl { DefaultDecl::Class(ClassExpr { ident, .. }) | DefaultDecl::Fn(FnExpr { ident, .. }) => ident.as_ref().map_or_else( || { ( magic_identifier::mangle("default export").into(), SyntaxContext::empty(), ) }, |ident| (ident.to_id()), ), DefaultDecl::TsInterfaceDecl(_) => { // not matching, might happen due to eventual consistency ( magic_identifier::mangle("default export").into(), SyntaxContext::empty(), ) } }, ); } fn visit_export_default_expr(&mut self, n: &ExportDefaultExpr) { self.data.has_exports = true; if self.comments.is_some() { // only visit children if we potentially need to mark import / requires n.visit_children_with(self); } self.data.exports.insert( rcstr!("default"), ( // `EsmModuleItem::code_generation` inserts this variable. magic_identifier::mangle("default export").into(), SyntaxContext::empty(), ), ); } fn visit_export_named_specifier(&mut self, n: &ExportNamedSpecifier) { let ModuleExportName::Ident(local) = &n.orig else { // This is only possible for re-exports, but they are already handled earlier in // visit_named_export. unreachable!("string reexports should have been already handled in visit_named_export"); }; let exported = n.exported.as_ref().unwrap_or(&n.orig); self.data .exports .insert(export_as_atom(exported).as_str().into(), local.to_id()); } fn visit_export_default_specifier(&mut self, n: &ExportDefaultSpecifier) { self.data .exports .insert(rcstr!("default"), n.exported.to_id()); } fn visit_program(&mut self, m: &Program) { self.data.has_top_level_await = has_top_level_await(m).is_some(); self.data.strict = match m { Program::Module(module) => module .body .iter() .take_while(|s| s.directive_continue()) .any(IsDirective::is_use_strict), Program::Script(script) => script .body .iter() .take_while(|s| s.directive_continue()) .any(IsDirective::is_use_strict), }; m.visit_children_with(self); } fn visit_stmt(&mut self, n: &Stmt) { if self.comments.is_some() { // only visit children if we potentially need to mark import / requires n.visit_children_with(self); } } /// check if import or require contains an ignore comment /// /// We are checking for the following cases: /// - import(/* webpackIgnore: true */ "a") /// - require(/* webpackIgnore: true */ "a") /// /// We can do this by checking if any of the comment spans are between the /// callee and the first argument. // // potentially support more webpack magic comments in the future: // https://webpack.js.org/api/module-methods/#magic-comments fn visit_call_expr(&mut self, n: &CallExpr) { // we could actually unwrap thanks to the optimisation above but it can't hurt to be safe... if let Some(comments) = self.comments { let callee_span = match &n.callee { Callee::Import(Import { span, .. }) => Some(*span), Callee::Expr(e) => Some(e.span()), _ => None, }; let ignore_directive = parse_ignore_directive(comments, n.args.first()); if let Some((callee_span, ignore_directive)) = callee_span.zip(ignore_directive) { self.data.attributes.insert( callee_span.lo, ImportAttributes { ignore: ignore_directive, }, ); }; } n.visit_children_with(self); } fn visit_new_expr(&mut self, n: &NewExpr) { // we could actually unwrap thanks to the optimisation above but it can't hurt to be safe... if let Some(comments) = self.comments { let callee_span = match &n.callee { box Expr::Ident(Ident { sym, .. }) if sym == "Worker" => Some(n.span), _ => None, }; let ignore_directive = parse_ignore_directive(comments, n.args.iter().flatten().next()); if let Some((callee_span, ignore_directive)) = callee_span.zip(ignore_directive) { self.data.attributes.insert( callee_span.lo, ImportAttributes { ignore: ignore_directive, }, ); }; } n.visit_children_with(self); } } fn parse_ignore_directive(comments: &dyn Comments, value: Option<&ExprOrSpread>) -> Option { // we are interested here in the last comment with a valid directive value .map(|arg| arg.span_lo()) .and_then(|comment_pos| comments.get_leading(comment_pos)) .iter() .flatten() .rev() .filter_map(|comment| { let (directive, value) = comment.text.trim().split_once(':')?; // support whitespace between the colon match (directive.trim(), value.trim()) { ("webpackIgnore" | "turbopackIgnore", "true") => Some(true), ("webpackIgnore" | "turbopackIgnore", "false") => Some(false), _ => None, // ignore anything else } }) .next() } pub(crate) fn orig_name(n: &ModuleExportName) -> Atom { match n { ModuleExportName::Ident(v) => v.sym.clone(), ModuleExportName::Str(v) => v.value.clone(), } } fn parse_with(with: Option<&ObjectLit>) -> Option { find_turbopack_part_id_in_asserts(with?).map(|v| match v { PartId::Internal(index, true) => ImportedSymbol::PartEvaluation(index), PartId::Internal(index, false) => ImportedSymbol::Part(index), PartId::ModuleEvaluation => ImportedSymbol::ModuleEvaluation, PartId::Export(e) => ImportedSymbol::Symbol(e.as_str().into()), PartId::Exports => ImportedSymbol::Exports, }) } fn get_import_symbol_from_import(specifier: &ImportSpecifier) -> ImportedSymbol { match specifier { ImportSpecifier::Named(ImportNamedSpecifier { local, imported, .. }) => ImportedSymbol::Symbol(match imported { Some(imported) => orig_name(imported), _ => local.sym.clone(), }), ImportSpecifier::Default(..) => ImportedSymbol::Symbol(atom!("default")), ImportSpecifier::Namespace(..) => ImportedSymbol::Exports, } } fn get_import_symbol_from_export(specifier: &ExportSpecifier) -> ImportedSymbol { match specifier { ExportSpecifier::Named(ExportNamedSpecifier { orig, .. }) => { ImportedSymbol::Symbol(orig_name(orig)) } ExportSpecifier::Default(..) => ImportedSymbol::Symbol(atom!("default")), ExportSpecifier::Namespace(..) => ImportedSymbol::Exports, } }