mod generated; use std::marker::PhantomData; use std::string::String as RustString; use itertools::Itertools; pub use self::generated::*; use crate::{ yellow::{RefRoot, SyntaxNodeChildren}, SmolStr, SyntaxKind::*, SyntaxNodeRef, }; /// The main trait to go from untyped `SyntaxNode` to a typed ast. The /// conversion itself has zero runtime cost: ast and syntax nodes have exactly /// the same representation: a pointer to the tree root and a pointer to the /// node itself. pub trait AstNode<'a>: Clone + Copy + 'a { fn cast(syntax: SyntaxNodeRef<'a>) -> Option where Self: Sized; fn syntax(self) -> SyntaxNodeRef<'a>; } pub trait NameOwner<'a>: AstNode<'a> { fn name(self) -> Option> { child_opt(self) } } pub trait VisibilityOwner<'a>: AstNode<'a> { fn visibility(self) -> Option> { child_opt(self) } } pub trait LoopBodyOwner<'a>: AstNode<'a> { fn loop_body(self) -> Option> { child_opt(self) } } pub trait ArgListOwner<'a>: AstNode<'a> { fn arg_list(self) -> Option> { child_opt(self) } } pub trait FnDefOwner<'a>: AstNode<'a> { fn functions(self) -> AstChildren<'a, FnDef<'a>> { children(self) } } // ModuleItem #[derive(Debug, Clone, Copy, PartialEq, Eq)] pub enum ItemOrMacro<'a> { Item(ModuleItem<'a>), Macro(MacroCall<'a>), } impl<'a> AstNode<'a> for ItemOrMacro<'a> { fn cast(syntax: SyntaxNodeRef<'a>) -> Option { let res = if let Some(item) = ModuleItem::cast(syntax) { ItemOrMacro::Item(item) } else if let Some(macro_call) = MacroCall::cast(syntax) { ItemOrMacro::Macro(macro_call) } else { return None; }; Some(res) } fn syntax(self) -> SyntaxNodeRef<'a> { match self { ItemOrMacro::Item(it) => it.syntax(), ItemOrMacro::Macro(it) => it.syntax(), } } } pub trait ModuleItemOwner<'a>: AstNode<'a> { fn items(self) -> AstChildren<'a, ModuleItem<'a>> { children(self) } fn items_with_macros(self) -> AstChildren<'a, ItemOrMacro<'a>> { children(self) } } pub trait TypeParamsOwner<'a>: AstNode<'a> { fn type_param_list(self) -> Option> { child_opt(self) } fn where_clause(self) -> Option> { child_opt(self) } } pub trait AttrsOwner<'a>: AstNode<'a> { fn attrs(self) -> AstChildren<'a, Attr<'a>> { children(self) } } pub trait DocCommentsOwner<'a>: AstNode<'a> { fn doc_comments(self) -> AstChildren<'a, Comment<'a>> { children(self) } /// Returns the textual content of a doc comment block as a single string. /// That is, strips leading `///` and joins lines fn doc_comment_text(self) -> RustString { self.doc_comments() .filter(|comment| comment.is_doc_comment()) .map(|comment| { let prefix = comment.prefix(); let trimmed = comment .text() .as_str() .trim() .trim_start_matches(prefix) .trim_start(); trimmed.to_owned() }) .join("\n") } } impl<'a> FnDef<'a> { pub fn has_atom_attr(&self, atom: &str) -> bool { self.attrs().filter_map(|x| x.as_atom()).any(|x| x == atom) } } impl<'a> Attr<'a> { pub fn as_atom(&self) -> Option { let tt = self.value()?; let (_bra, attr, _ket) = tt.syntax().children().collect_tuple()?; if attr.kind() == IDENT { Some(attr.leaf_text().unwrap().clone()) } else { None } } pub fn as_call(&self) -> Option<(SmolStr, TokenTree<'a>)> { let tt = self.value()?; let (_bra, attr, args, _ket) = tt.syntax().children().collect_tuple()?; let args = TokenTree::cast(args)?; if attr.kind() == IDENT { Some((attr.leaf_text().unwrap().clone(), args)) } else { None } } } impl<'a> Lifetime<'a> { pub fn text(&self) -> SmolStr { self.syntax().leaf_text().unwrap().clone() } } impl<'a> Char<'a> { pub fn text(&self) -> &SmolStr { &self.syntax().leaf_text().unwrap() } } impl<'a> Byte<'a> { pub fn text(&self) -> &SmolStr { &self.syntax().leaf_text().unwrap() } } impl<'a> ByteString<'a> { pub fn text(&self) -> &SmolStr { &self.syntax().leaf_text().unwrap() } } impl<'a> String<'a> { pub fn text(&self) -> &SmolStr { &self.syntax().leaf_text().unwrap() } } impl<'a> Comment<'a> { pub fn text(&self) -> &SmolStr { self.syntax().leaf_text().unwrap() } pub fn flavor(&self) -> CommentFlavor { let text = self.text(); if text.starts_with("///") { CommentFlavor::Doc } else if text.starts_with("//!") { CommentFlavor::ModuleDoc } else if text.starts_with("//") { CommentFlavor::Line } else { CommentFlavor::Multiline } } pub fn is_doc_comment(&self) -> bool { self.flavor().is_doc_comment() } pub fn prefix(&self) -> &'static str { self.flavor().prefix() } pub fn count_newlines_lazy(&self) -> impl Iterator { self.text().chars().filter(|&c| c == '\n').map(|_| &()) } pub fn has_newlines(&self) -> bool { self.count_newlines_lazy().count() > 0 } } #[derive(Debug, PartialEq, Eq)] pub enum CommentFlavor { Line, Doc, ModuleDoc, Multiline, } impl CommentFlavor { pub fn prefix(&self) -> &'static str { use self::CommentFlavor::*; match *self { Line => "//", Doc => "///", ModuleDoc => "//!", Multiline => "/*", } } pub fn is_doc_comment(&self) -> bool { match self { CommentFlavor::Doc | CommentFlavor::ModuleDoc => true, _ => false, } } } impl<'a> Whitespace<'a> { pub fn text(&self) -> &SmolStr { &self.syntax().leaf_text().unwrap() } pub fn count_newlines_lazy(&self) -> impl Iterator { self.text().chars().filter(|&c| c == '\n').map(|_| &()) } pub fn has_newlines(&self) -> bool { self.count_newlines_lazy().count() > 0 } } impl<'a> Name<'a> { pub fn text(&self) -> SmolStr { let ident = self.syntax().first_child().unwrap(); ident.leaf_text().unwrap().clone() } } impl<'a> NameRef<'a> { pub fn text(&self) -> SmolStr { let ident = self.syntax().first_child().unwrap(); ident.leaf_text().unwrap().clone() } } impl<'a> ImplItem<'a> { pub fn target_type(self) -> Option> { match self.target() { (Some(t), None) | (_, Some(t)) => Some(t), _ => None, } } pub fn target_trait(self) -> Option> { match self.target() { (Some(t), Some(_)) => Some(t), _ => None, } } fn target(self) -> (Option>, Option>) { let mut types = children(self); let first = types.next(); let second = types.next(); (first, second) } } impl<'a> Module<'a> { pub fn has_semi(self) -> bool { match self.syntax().last_child() { None => false, Some(node) => node.kind() == SEMI, } } } impl<'a> LetStmt<'a> { pub fn has_semi(self) -> bool { match self.syntax().last_child() { None => false, Some(node) => node.kind() == SEMI, } } } impl<'a> IfExpr<'a> { pub fn then_branch(self) -> Option> { self.blocks().nth(0) } pub fn else_branch(self) -> Option> { self.blocks().nth(1) } fn blocks(self) -> AstChildren<'a, Block<'a>> { children(self) } } #[derive(Debug, Clone, Copy, PartialEq, Eq)] pub enum PathSegmentKind<'a> { Name(NameRef<'a>), SelfKw, SuperKw, CrateKw, } impl<'a> PathSegment<'a> { pub fn parent_path(self) -> Path<'a> { self.syntax() .parent() .and_then(Path::cast) .expect("segments are always nested in paths") } pub fn kind(self) -> Option> { let res = if let Some(name_ref) = self.name_ref() { PathSegmentKind::Name(name_ref) } else { match self.syntax().first_child()?.kind() { SELF_KW => PathSegmentKind::SelfKw, SUPER_KW => PathSegmentKind::SuperKw, CRATE_KW => PathSegmentKind::CrateKw, _ => return None, } }; Some(res) } } impl<'a> UseTree<'a> { pub fn has_star(self) -> bool { self.syntax().children().any(|it| it.kind() == STAR) } } impl<'a> UseTreeList<'a> { pub fn parent_use_tree(self) -> UseTree<'a> { self.syntax() .parent() .and_then(UseTree::cast) .expect("UseTreeLists are always nested in UseTrees") } } fn child_opt<'a, P: AstNode<'a>, C: AstNode<'a>>(parent: P) -> Option { children(parent).next() } fn children<'a, P: AstNode<'a>, C: AstNode<'a>>(parent: P) -> AstChildren<'a, C> { AstChildren::new(parent.syntax()) } #[derive(Debug)] pub struct AstChildren<'a, N> { inner: SyntaxNodeChildren>, ph: PhantomData, } impl<'a, N> AstChildren<'a, N> { fn new(parent: SyntaxNodeRef<'a>) -> Self { AstChildren { inner: parent.children(), ph: PhantomData, } } } impl<'a, N: AstNode<'a>> Iterator for AstChildren<'a, N> { type Item = N; fn next(&mut self) -> Option { loop { if let Some(n) = N::cast(self.inner.next()?) { return Some(n); } } } } #[derive(Debug, Clone, PartialEq, Eq)] pub enum StructFlavor<'a> { Tuple(PosFieldList<'a>), Named(NamedFieldDefList<'a>), Unit, } impl<'a> StructFlavor<'a> { fn from_node>(node: N) -> StructFlavor<'a> { if let Some(nfdl) = child_opt::<_, NamedFieldDefList>(node) { StructFlavor::Named(nfdl) } else if let Some(pfl) = child_opt::<_, PosFieldList>(node) { StructFlavor::Tuple(pfl) } else { StructFlavor::Unit } } } impl<'a> StructDef<'a> { pub fn flavor(self) -> StructFlavor<'a> { StructFlavor::from_node(self) } } impl<'a> EnumVariant<'a> { pub fn flavor(self) -> StructFlavor<'a> { StructFlavor::from_node(self) } } impl<'a> PointerType<'a> { pub fn is_mut(&self) -> bool { self.syntax().children().any(|n| n.kind() == MUT_KW) } } impl<'a> ReferenceType<'a> { pub fn is_mut(&self) -> bool { self.syntax().children().any(|n| n.kind() == MUT_KW) } } impl<'a> RefExpr<'a> { pub fn is_mut(&self) -> bool { self.syntax().children().any(|n| n.kind() == MUT_KW) } } #[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)] pub enum PrefixOp { /// The `*` operator for dereferencing Deref, /// The `!` operator for logical inversion Not, /// The `-` operator for negation Neg, } impl<'a> PrefixExpr<'a> { pub fn op(&self) -> Option { match self.syntax().first_child()?.kind() { STAR => Some(PrefixOp::Deref), EXCL => Some(PrefixOp::Not), MINUS => Some(PrefixOp::Neg), _ => None, } } } #[test] fn test_doc_comment_of_items() { let file = SourceFileNode::parse( r#" //! doc // non-doc mod foo {} "#, ); let module = file.syntax().descendants().find_map(Module::cast).unwrap(); assert_eq!("doc", module.doc_comment_text()); }