//! Various traits that are implemented by ast nodes. //! //! The implementations are usually trivial, and live in generated.rs use stdx::SepBy; use crate::{ ast::{self, support, AstChildren, AstNode, AstToken}, syntax_node::SyntaxElementChildren, SyntaxToken, T, }; pub trait TypeAscriptionOwner: AstNode { fn ascribed_type(&self) -> Option<ast::TypeRef> { support::child(self.syntax()) } } pub trait NameOwner: AstNode { fn name(&self) -> Option<ast::Name> { support::child(self.syntax()) } } pub trait VisibilityOwner: AstNode { fn visibility(&self) -> Option<ast::Visibility> { support::child(self.syntax()) } } pub trait LoopBodyOwner: AstNode { fn loop_body(&self) -> Option<ast::BlockExpr> { support::child(self.syntax()) } fn label(&self) -> Option<ast::Label> { support::child(self.syntax()) } } pub trait ArgListOwner: AstNode { fn arg_list(&self) -> Option<ast::ArgList> { support::child(self.syntax()) } } pub trait ModuleItemOwner: AstNode { fn items(&self) -> AstChildren<ast::ModuleItem> { support::children(self.syntax()) } } pub trait TypeParamsOwner: AstNode { fn type_param_list(&self) -> Option<ast::TypeParamList> { support::child(self.syntax()) } fn where_clause(&self) -> Option<ast::WhereClause> { support::child(self.syntax()) } } pub trait TypeBoundsOwner: AstNode { fn type_bound_list(&self) -> Option<ast::TypeBoundList> { support::child(self.syntax()) } fn colon_token(&self) -> Option<SyntaxToken> { support::token(self.syntax(), T![:]) } } pub trait AttrsOwner: AstNode { fn attrs(&self) -> AstChildren<ast::Attr> { support::children(self.syntax()) } fn has_atom_attr(&self, atom: &str) -> bool { self.attrs().filter_map(|x| x.as_simple_atom()).any(|x| x == atom) } } pub trait DocCommentsOwner: AstNode { fn doc_comments(&self) -> CommentIter { CommentIter { iter: self.syntax().children_with_tokens() } } /// Returns the textual content of a doc comment block as a single string. /// That is, strips leading `///` (+ optional 1 character of whitespace), /// trailing `*/`, trailing whitespace and then joins the lines. fn doc_comment_text(&self) -> Option<String> { let mut has_comments = false; let docs = self .doc_comments() .filter(|comment| comment.kind().doc.is_some()) .map(|comment| { has_comments = true; let prefix_len = comment.prefix().len(); let line: &str = comment.text().as_str(); // Determine if the prefix or prefix + 1 char is stripped let pos = if let Some(ws) = line.chars().nth(prefix_len).filter(|c| c.is_whitespace()) { prefix_len + ws.len_utf8() } else { prefix_len }; let end = if comment.kind().shape.is_block() && line.ends_with("*/") { line.len() - 2 } else { line.len() }; // Note that we do not trim the end of the line here // since whitespace can have special meaning at the end // of a line in markdown. line[pos..end].to_owned() }) .sep_by("\n") .to_string(); if has_comments { Some(docs) } else { None } } } pub struct CommentIter { iter: SyntaxElementChildren, } impl Iterator for CommentIter { type Item = ast::Comment; fn next(&mut self) -> Option<ast::Comment> { self.iter.by_ref().find_map(|el| el.into_token().and_then(ast::Comment::cast)) } }