diff --git a/crates/ide-db/src/source_change.rs b/crates/ide-db/src/source_change.rs index 936354f2961..1cc7be68138 100644 --- a/crates/ide-db/src/source_change.rs +++ b/crates/ide-db/src/source_change.rs @@ -7,7 +7,7 @@ use base_db::{AnchoredPathBuf, FileId}; use stdx::{hash::NoHashHashMap, never}; -use syntax::{algo, AstNode, SyntaxNode, SyntaxNodePtr, TextRange, TextSize}; +use syntax::{algo, ast, ted, AstNode, SyntaxNode, SyntaxNodePtr, TextRange, TextSize}; use text_edit::{TextEdit, TextEditBuilder}; use crate::SnippetCap; @@ -99,6 +99,8 @@ pub struct SourceChangeBuilder { /// Maps the original, immutable `SyntaxNode` to a `clone_for_update` twin. pub mutated_tree: Option, + /// Keeps track of where to place snippets + pub snippet_builder: Option, } pub struct TreeMutator { @@ -106,6 +108,12 @@ pub struct TreeMutator { mutable_clone: SyntaxNode, } +#[derive(Default)] +pub struct SnippetBuilder { + /// Where to place snippets at + places: Vec, +} + impl TreeMutator { pub fn new(immutable: &SyntaxNode) -> TreeMutator { let immutable = immutable.ancestors().last().unwrap(); @@ -131,6 +139,7 @@ pub fn new(file_id: FileId) -> SourceChangeBuilder { source_change: SourceChange::default(), trigger_signature_help: false, mutated_tree: None, + snippet_builder: None, } } @@ -140,6 +149,17 @@ pub fn edit_file(&mut self, file_id: FileId) { } fn commit(&mut self) { + // Render snippets first so that they get bundled into the tree diff + if let Some(mut snippets) = self.snippet_builder.take() { + // Last snippet always has stop index 0 + let last_stop = snippets.places.pop().unwrap(); + last_stop.place(0); + + for (index, stop) in snippets.places.into_iter().enumerate() { + stop.place(index + 1) + } + } + if let Some(tm) = self.mutated_tree.take() { algo::diff(&tm.immutable, &tm.mutable_clone).into_text_edit(&mut self.edit) } @@ -214,6 +234,33 @@ pub fn trigger_signature_help(&mut self) { self.trigger_signature_help = true; } + /// Adds a tabstop snippet to place the cursor before `node` + pub fn add_tabstop_before(&mut self, _cap: SnippetCap, node: impl AstNode) { + assert!(node.syntax().parent().is_some()); + + let snippet_builder = self.snippet_builder.get_or_insert(SnippetBuilder { places: vec![] }); + snippet_builder.places.push(PlaceSnippet::Before(node.syntax().clone())); + self.source_change.is_snippet = true; + } + + /// Adds a tabstop snippet to place the cursor after `node` + pub fn add_tabstop_after(&mut self, _cap: SnippetCap, node: impl AstNode) { + assert!(node.syntax().parent().is_some()); + + let snippet_builder = self.snippet_builder.get_or_insert(SnippetBuilder { places: vec![] }); + snippet_builder.places.push(PlaceSnippet::After(node.syntax().clone())); + self.source_change.is_snippet = true; + } + + /// Adds a snippet to move the cursor selected over `node` + pub fn add_placeholder_snippet(&mut self, _cap: SnippetCap, node: impl AstNode) { + assert!(node.syntax().parent().is_some()); + + let snippet_builder = self.snippet_builder.get_or_insert(SnippetBuilder { places: vec![] }); + snippet_builder.places.push(PlaceSnippet::Over(node.syntax().clone())); + self.source_change.is_snippet = true; + } + pub fn finish(mut self) -> SourceChange { self.commit(); mem::take(&mut self.source_change) @@ -236,3 +283,66 @@ fn from(edit: FileSystemEdit) -> SourceChange { } } } + +enum PlaceSnippet { + /// Place a tabstop before a node + Before(SyntaxNode), + /// Place a tabstop before a node + After(SyntaxNode), + /// Place a placeholder snippet in place of the node + Over(SyntaxNode), +} + +impl PlaceSnippet { + /// Places the snippet before or over a node with the given tab stop index + fn place(self, order: usize) { + // ensure the target node is still attached + match &self { + PlaceSnippet::Before(node) | PlaceSnippet::After(node) | PlaceSnippet::Over(node) => { + // node should still be in the tree, but if it isn't + // then it's okay to just ignore this place + if stdx::never!(node.parent().is_none()) { + return; + } + } + } + + match self { + PlaceSnippet::Before(node) => { + ted::insert_raw(ted::Position::before(&node), Self::make_tab_stop(order)); + } + PlaceSnippet::After(node) => { + ted::insert_raw(ted::Position::after(&node), Self::make_tab_stop(order)); + } + PlaceSnippet::Over(node) => { + let position = ted::Position::before(&node); + node.detach(); + + let snippet = ast::SourceFile::parse(&format!("${{{order}:_}}")) + .syntax_node() + .clone_for_update(); + + let placeholder = + snippet.descendants().find_map(ast::UnderscoreExpr::cast).unwrap(); + ted::replace(placeholder.syntax(), node); + + ted::insert_raw(position, snippet); + } + } + } + + fn make_tab_stop(order: usize) -> SyntaxNode { + let stop = ast::SourceFile::parse(&format!("stop!(${order})")) + .syntax_node() + .descendants() + .find_map(ast::TokenTree::cast) + .unwrap() + .syntax() + .clone_for_update(); + + stop.first_token().unwrap().detach(); + stop.last_token().unwrap().detach(); + + stop + } +}