From 757e593b253b4df7e6fc8bf15a4d4f34c9d484c5 Mon Sep 17 00:00:00 2001 From: Aleksey Kladov Date: Wed, 27 Nov 2019 21:32:33 +0300 Subject: rename ra_ide_api -> ra_ide --- crates/ra_ide/src/expand_macro.rs | 295 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 295 insertions(+) create mode 100644 crates/ra_ide/src/expand_macro.rs (limited to 'crates/ra_ide/src/expand_macro.rs') diff --git a/crates/ra_ide/src/expand_macro.rs b/crates/ra_ide/src/expand_macro.rs new file mode 100644 index 000000000..abc602244 --- /dev/null +++ b/crates/ra_ide/src/expand_macro.rs @@ -0,0 +1,295 @@ +//! This modules implements "expand macro" functionality in the IDE + +use crate::{db::RootDatabase, FilePosition}; +use hir::db::AstDatabase; +use ra_db::SourceDatabase; +use rustc_hash::FxHashMap; + +use ra_syntax::{ + algo::{find_node_at_offset, replace_descendants}, + ast::{self}, + AstNode, NodeOrToken, SyntaxKind, SyntaxNode, WalkEvent, T, +}; + +pub struct ExpandedMacro { + pub name: String, + pub expansion: String, +} + +pub(crate) fn expand_macro(db: &RootDatabase, position: FilePosition) -> Option { + let parse = db.parse(position.file_id); + let file = parse.tree(); + let name_ref = find_node_at_offset::(file.syntax(), position.offset)?; + let mac = name_ref.syntax().ancestors().find_map(ast::MacroCall::cast)?; + + let source = hir::Source::new(position.file_id.into(), mac.syntax()); + let expanded = expand_macro_recur(db, source, source.with_value(&mac))?; + + // FIXME: + // macro expansion may lose all white space information + // But we hope someday we can use ra_fmt for that + let expansion = insert_whitespaces(expanded); + Some(ExpandedMacro { name: name_ref.text().to_string(), expansion }) +} + +fn expand_macro_recur( + db: &RootDatabase, + source: hir::Source<&SyntaxNode>, + macro_call: hir::Source<&ast::MacroCall>, +) -> Option { + let analyzer = hir::SourceAnalyzer::new(db, source, None); + let expansion = analyzer.expand(db, macro_call)?; + let macro_file_id = expansion.file_id(); + let mut expanded: SyntaxNode = db.parse_or_expand(macro_file_id)?; + + let children = expanded.descendants().filter_map(ast::MacroCall::cast); + let mut replaces = FxHashMap::default(); + + for child in children.into_iter() { + let node = hir::Source::new(macro_file_id, &child); + if let Some(new_node) = expand_macro_recur(db, source, node) { + // Replace the whole node if it is root + // `replace_descendants` will not replace the parent node + // but `SyntaxNode::descendants include itself + if expanded == *child.syntax() { + expanded = new_node; + } else { + replaces.insert(child.syntax().clone().into(), new_node.into()); + } + } + } + + Some(replace_descendants(&expanded, &replaces)) +} + +// FIXME: It would also be cool to share logic here and in the mbe tests, +// which are pretty unreadable at the moment. +fn insert_whitespaces(syn: SyntaxNode) -> String { + use SyntaxKind::*; + + let mut res = String::new(); + let mut token_iter = syn + .preorder_with_tokens() + .filter_map(|event| { + if let WalkEvent::Enter(NodeOrToken::Token(token)) = event { + Some(token) + } else { + None + } + }) + .peekable(); + + let mut indent = 0; + let mut last: Option = None; + + while let Some(token) = token_iter.next() { + let mut is_next = |f: fn(SyntaxKind) -> bool, default| -> bool { + token_iter.peek().map(|it| f(it.kind())).unwrap_or(default) + }; + let is_last = |f: fn(SyntaxKind) -> bool, default| -> bool { + last.map(|it| f(it)).unwrap_or(default) + }; + + res += &match token.kind() { + k @ _ if is_text(k) && is_next(|it| !it.is_punct(), true) => { + token.text().to_string() + " " + } + L_CURLY if is_next(|it| it != R_CURLY, true) => { + indent += 1; + let leading_space = if is_last(|it| is_text(it), false) { " " } else { "" }; + format!("{}{{\n{}", leading_space, " ".repeat(indent)) + } + R_CURLY if is_last(|it| it != L_CURLY, true) => { + indent = indent.checked_sub(1).unwrap_or(0); + format!("\n{}}}", " ".repeat(indent)) + } + R_CURLY => format!("}}\n{}", " ".repeat(indent)), + T![;] => format!(";\n{}", " ".repeat(indent)), + T![->] => " -> ".to_string(), + T![=] => " = ".to_string(), + T![=>] => " => ".to_string(), + _ => token.text().to_string(), + }; + + last = Some(token.kind()); + } + + return res; + + fn is_text(k: SyntaxKind) -> bool { + k.is_keyword() || k.is_literal() || k == IDENT + } +} + +#[cfg(test)] +mod tests { + use super::*; + use crate::mock_analysis::analysis_and_position; + use insta::assert_snapshot; + + fn check_expand_macro(fixture: &str) -> ExpandedMacro { + let (analysis, pos) = analysis_and_position(fixture); + analysis.expand_macro(pos).unwrap().unwrap() + } + + #[test] + fn macro_expand_recursive_expansion() { + let res = check_expand_macro( + r#" + //- /lib.rs + macro_rules! bar { + () => { fn b() {} } + } + macro_rules! foo { + () => { bar!(); } + } + macro_rules! baz { + () => { foo!(); } + } + f<|>oo!(); + "#, + ); + + assert_eq!(res.name, "foo"); + assert_snapshot!(res.expansion, @r###" +fn b(){} +"###); + } + + #[test] + fn macro_expand_multiple_lines() { + let res = check_expand_macro( + r#" + //- /lib.rs + macro_rules! foo { + () => { + fn some_thing() -> u32 { + let a = 0; + a + 10 + } + } + } + f<|>oo!(); + "#, + ); + + assert_eq!(res.name, "foo"); + assert_snapshot!(res.expansion, @r###" +fn some_thing() -> u32 { + let a = 0; + a+10 +} +"###); + } + + #[test] + fn macro_expand_match_ast() { + let res = check_expand_macro( + r#" + //- /lib.rs + macro_rules! match_ast { + (match $node:ident { $($tt:tt)* }) => { match_ast!(match ($node) { $($tt)* }) }; + + (match ($node:expr) { + $( ast::$ast:ident($it:ident) => $res:block, )* + _ => $catch_all:expr $(,)? + }) => {{ + $( if let Some($it) = ast::$ast::cast($node.clone()) $res else )* + { $catch_all } + }}; + } + + fn main() { + mat<|>ch_ast! { + match container { + ast::TraitDef(it) => {}, + ast::ImplBlock(it) => {}, + _ => { continue }, + } + } + } + "#, + ); + + assert_eq!(res.name, "match_ast"); + assert_snapshot!(res.expansion, @r###" +{ + if let Some(it) = ast::TraitDef::cast(container.clone()){} + else if let Some(it) = ast::ImplBlock::cast(container.clone()){} + else { + { + continue + } + } +} +"###); + } + + #[test] + fn macro_expand_match_ast_inside_let_statement() { + let res = check_expand_macro( + r#" + //- /lib.rs + macro_rules! match_ast { + (match $node:ident { $($tt:tt)* }) => { match_ast!(match ($node) { $($tt)* }) }; + (match ($node:expr) {}) => {{}}; + } + + fn main() { + let p = f(|it| { + let res = mat<|>ch_ast! { match c {}}; + Some(res) + })?; + } + "#, + ); + + assert_eq!(res.name, "match_ast"); + assert_snapshot!(res.expansion, @r###"{}"###); + } + + #[test] + fn macro_expand_inner_macro_fail_to_expand() { + let res = check_expand_macro( + r#" + //- /lib.rs + macro_rules! bar { + (BAD) => {}; + } + macro_rules! foo { + () => {bar!()}; + } + + fn main() { + let res = fo<|>o!(); + } + "#, + ); + + assert_eq!(res.name, "foo"); + assert_snapshot!(res.expansion, @r###"bar!()"###); + } + + #[test] + fn macro_expand_with_dollar_crate() { + let res = check_expand_macro( + r#" + //- /lib.rs + #[macro_export] + macro_rules! bar { + () => {0}; + } + macro_rules! foo { + () => {$crate::bar!()}; + } + + fn main() { + let res = fo<|>o!(); + } + "#, + ); + + assert_eq!(res.name, "foo"); + assert_snapshot!(res.expansion, @r###"0"###); + } +} -- cgit v1.2.3