rename ra_editor -> ra_ide_api_light

crates/ra_ide_api_light/src/typing.rs

@@ -0,0 +1,826 @@
+use std::mem;
+
+use itertools::Itertools;
+use ra_syntax::{
+    algo::{find_node_at_offset, find_covering_node, find_leaf_at_offset, LeafAtOffset},
+    ast,
+    AstNode, Direction, SourceFile, SyntaxKind,
+    SyntaxKind::*,
+    SyntaxNode, TextRange, TextUnit,
+};
+
+use crate::{LocalEdit, TextEditBuilder};
+
+pub fn join_lines(file: &SourceFile, range: TextRange) -> LocalEdit {
+    let range = if range.is_empty() {
+        let syntax = file.syntax();
+        let text = syntax.text().slice(range.start()..);
+        let pos = match text.find('\n') {
+            None => {
+                return LocalEdit {
+                    label: "join lines".to_string(),
+                    edit: TextEditBuilder::default().finish(),
+                    cursor_position: None,
+                };
+            }
+            Some(pos) => pos,
+        };
+        TextRange::offset_len(range.start() + pos, TextUnit::of_char('\n'))
+    } else {
+        range
+    };
+
+    let node = find_covering_node(file.syntax(), range);
+    let mut edit = TextEditBuilder::default();
+    for node in node.descendants() {
+        let text = match node.leaf_text() {
+            Some(text) => text,
+            None => continue,
+        };
+        let range = match range.intersection(&node.range()) {
+            Some(range) => range,
+            None => continue,
+        } - node.range().start();
+        for (pos, _) in text[range].bytes().enumerate().filter(|&(_, b)| b == b'\n') {
+            let pos: TextUnit = (pos as u32).into();
+            let off = node.range().start() + range.start() + pos;
+            if !edit.invalidates_offset(off) {
+                remove_newline(&mut edit, node, text.as_str(), off);
+            }
+        }
+    }
+
+    LocalEdit {
+        label: "join lines".to_string(),
+        edit: edit.finish(),
+        cursor_position: None,
+    }
+}
+
+pub fn on_enter(file: &SourceFile, offset: TextUnit) -> Option<LocalEdit> {
+    let comment = find_leaf_at_offset(file.syntax(), offset)
+        .left_biased()
+        .and_then(ast::Comment::cast)?;
+
+    if let ast::CommentFlavor::Multiline = comment.flavor() {
+        return None;
+    }
+
+    let prefix = comment.prefix();
+    if offset < comment.syntax().range().start() + TextUnit::of_str(prefix) + TextUnit::from(1) {
+        return None;
+    }
+
+    let indent = node_indent(file, comment.syntax())?;
+    let inserted = format!("\n{}{} ", indent, prefix);
+    let cursor_position = offset + TextUnit::of_str(&inserted);
+    let mut edit = TextEditBuilder::default();
+    edit.insert(offset, inserted);
+    Some(LocalEdit {
+        label: "on enter".to_string(),
+        edit: edit.finish(),
+        cursor_position: Some(cursor_position),
+    })
+}
+
+fn node_indent<'a>(file: &'a SourceFile, node: &SyntaxNode) -> Option<&'a str> {
+    let ws = match find_leaf_at_offset(file.syntax(), node.range().start()) {
+        LeafAtOffset::Between(l, r) => {
+            assert!(r == node);
+            l
+        }
+        LeafAtOffset::Single(n) => {
+            assert!(n == node);
+            return Some("");
+        }
+        LeafAtOffset::None => unreachable!(),
+    };
+    if ws.kind() != WHITESPACE {
+        return None;
+    }
+    let text = ws.leaf_text().unwrap();
+    let pos = text.as_str().rfind('\n').map(|it| it + 1).unwrap_or(0);
+    Some(&text[pos..])
+}
+
+pub fn on_eq_typed(file: &SourceFile, offset: TextUnit) -> Option<LocalEdit> {
+    let let_stmt: &ast::LetStmt = find_node_at_offset(file.syntax(), offset)?;
+    if let_stmt.has_semi() {
+        return None;
+    }
+    if let Some(expr) = let_stmt.initializer() {
+        let expr_range = expr.syntax().range();
+        if expr_range.contains(offset) && offset != expr_range.start() {
+            return None;
+        }
+        if file
+            .syntax()
+            .text()
+            .slice(offset..expr_range.start())
+            .contains('\n')
+        {
+            return None;
+        }
+    } else {
+        return None;
+    }
+    let offset = let_stmt.syntax().range().end();
+    let mut edit = TextEditBuilder::default();
+    edit.insert(offset, ";".to_string());
+    Some(LocalEdit {
+        label: "add semicolon".to_string(),
+        edit: edit.finish(),
+        cursor_position: None,
+    })
+}
+
+pub fn on_dot_typed(file: &SourceFile, offset: TextUnit) -> Option<LocalEdit> {
+    let before_dot_offset = offset - TextUnit::of_char('.');
+
+    let whitespace = find_leaf_at_offset(file.syntax(), before_dot_offset).left_biased()?;
+
+    // find whitespace just left of the dot
+    ast::Whitespace::cast(whitespace)?;
+
+    // make sure there is a method call
+    let method_call = whitespace
+        .siblings(Direction::Prev)
+        // first is whitespace
+        .skip(1)
+        .next()?;
+
+    ast::MethodCallExpr::cast(method_call)?;
+
+    // find how much the _method call is indented
+    let method_chain_indent = method_call
+        .parent()?
+        .siblings(Direction::Prev)
+        .skip(1)
+        .next()?
+        .leaf_text()
+        .map(|x| last_line_indent_in_whitespace(x))?;
+
+    let current_indent = TextUnit::of_str(last_line_indent_in_whitespace(whitespace.leaf_text()?));
+    // TODO: indent is always 4 spaces now. A better heuristic could look on the previous line(s)
+
+    let target_indent = TextUnit::of_str(method_chain_indent) + TextUnit::from_usize(4);
+
+    let diff = target_indent - current_indent;
+
+    let indent = "".repeat(diff.to_usize());
+
+    let cursor_position = offset + diff;
+    let mut edit = TextEditBuilder::default();
+    edit.insert(before_dot_offset, indent);
+    Some(LocalEdit {
+        label: "indent dot".to_string(),
+        edit: edit.finish(),
+        cursor_position: Some(cursor_position),
+    })
+}
+
+/// Finds the last line in the whitespace
+fn last_line_indent_in_whitespace(ws: &str) -> &str {
+    ws.split('\n').last().unwrap_or("")
+}
+
+fn remove_newline(
+    edit: &mut TextEditBuilder,
+    node: &SyntaxNode,
+    node_text: &str,
+    offset: TextUnit,
+) {
+    if node.kind() != WHITESPACE || node_text.bytes().filter(|&b| b == b'\n').count() != 1 {
+        // The node is either the first or the last in the file
+        let suff = &node_text[TextRange::from_to(
+            offset - node.range().start() + TextUnit::of_char('\n'),
+            TextUnit::of_str(node_text),
+        )];
+        let spaces = suff.bytes().take_while(|&b| b == b' ').count();
+
+        edit.replace(
+            TextRange::offset_len(offset, ((spaces + 1) as u32).into()),
+            " ".to_string(),
+        );
+        return;
+    }
+
+    // Special case that turns something like:
+    //
+    // ```
+    // my_function({<|>
+    //    <some-expr>
+    // })
+    // ```
+    //
+    // into `my_function(<some-expr>)`
+    if join_single_expr_block(edit, node).is_some() {
+        return;
+    }
+    // ditto for
+    //
+    // ```
+    // use foo::{<|>
+    //    bar
+    // };
+    // ```
+    if join_single_use_tree(edit, node).is_some() {
+        return;
+    }
+
+    // The node is between two other nodes
+    let prev = node.prev_sibling().unwrap();
+    let next = node.next_sibling().unwrap();
+    if is_trailing_comma(prev.kind(), next.kind()) {
+        // Removes: trailing comma, newline (incl. surrounding whitespace)
+        edit.delete(TextRange::from_to(prev.range().start(), node.range().end()));
+    } else if prev.kind() == COMMA && next.kind() == R_CURLY {
+        // Removes: comma, newline (incl. surrounding whitespace)
+        let space = if let Some(left) = prev.prev_sibling() {
+            compute_ws(left, next)
+        } else {
+            " "
+        };
+        edit.replace(
+            TextRange::from_to(prev.range().start(), node.range().end()),
+            space.to_string(),
+        );
+    } else if let (Some(_), Some(next)) = (ast::Comment::cast(prev), ast::Comment::cast(next)) {
+        // Removes: newline (incl. surrounding whitespace), start of the next comment
+        edit.delete(TextRange::from_to(
+            node.range().start(),
+            next.syntax().range().start() + TextUnit::of_str(next.prefix()),
+        ));
+    } else {
+        // Remove newline but add a computed amount of whitespace characters
+        edit.replace(node.range(), compute_ws(prev, next).to_string());
+    }
+}
+
+fn is_trailing_comma(left: SyntaxKind, right: SyntaxKind) -> bool {
+    match (left, right) {
+        (COMMA, R_PAREN) | (COMMA, R_BRACK) => true,
+        _ => false,
+    }
+}
+
+fn join_single_expr_block(edit: &mut TextEditBuilder, node: &SyntaxNode) -> Option<()> {
+    let block = ast::Block::cast(node.parent()?)?;
+    let block_expr = ast::BlockExpr::cast(block.syntax().parent()?)?;
+    let expr = single_expr(block)?;
+    edit.replace(
+        block_expr.syntax().range(),
+        expr.syntax().text().to_string(),
+    );
+    Some(())
+}
+
+fn single_expr(block: &ast::Block) -> Option<&ast::Expr> {
+    let mut res = None;
+    for child in block.syntax().children() {
+        if let Some(expr) = ast::Expr::cast(child) {
+            if expr.syntax().text().contains('\n') {
+                return None;
+            }
+            if mem::replace(&mut res, Some(expr)).is_some() {
+                return None;
+            }
+        } else {
+            match child.kind() {
+                WHITESPACE | L_CURLY | R_CURLY => (),
+                _ => return None,
+            }
+        }
+    }
+    res
+}
+
+fn join_single_use_tree(edit: &mut TextEditBuilder, node: &SyntaxNode) -> Option<()> {
+    let use_tree_list = ast::UseTreeList::cast(node.parent()?)?;
+    let (tree,) = use_tree_list.use_trees().collect_tuple()?;
+    edit.replace(
+        use_tree_list.syntax().range(),
+        tree.syntax().text().to_string(),
+    );
+    Some(())
+}
+
+fn compute_ws(left: &SyntaxNode, right: &SyntaxNode) -> &'static str {
+    match left.kind() {
+        L_PAREN | L_BRACK => return "",
+        L_CURLY => {
+            if let USE_TREE = right.kind() {
+                return "";
+            }
+        }
+        _ => (),
+    }
+    match right.kind() {
+        R_PAREN | R_BRACK => return "",
+        R_CURLY => {
+            if let USE_TREE = left.kind() {
+                return "";
+            }
+        }
+        DOT => return "",
+        _ => (),
+    }
+    " "
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::test_utils::{
+        add_cursor, assert_eq_text, check_action, extract_offset, extract_range,
+};
+
+    fn check_join_lines(before: &str, after: &str) {
+        check_action(before, after, |file, offset| {
+            let range = TextRange::offset_len(offset, 0.into());
+            let res = join_lines(file, range);
+            Some(res)
+        })
+    }
+
+    #[test]
+    fn test_join_lines_comma() {
+        check_join_lines(
+            r"
+fn foo() {
+    <|>foo(1,
+    )
+}
+",
+            r"
+fn foo() {
+    <|>foo(1)
+}
+",
+        );
+    }
+
+    #[test]
+    fn test_join_lines_lambda_block() {
+        check_join_lines(
+            r"
+pub fn reparse(&self, edit: &AtomTextEdit) -> File {
+    <|>self.incremental_reparse(edit).unwrap_or_else(|| {
+        self.full_reparse(edit)
+    })
+}
+",
+            r"
+pub fn reparse(&self, edit: &AtomTextEdit) -> File {
+    <|>self.incremental_reparse(edit).unwrap_or_else(|| self.full_reparse(edit))
+}
+",
+        );
+    }
+
+    #[test]
+    fn test_join_lines_block() {
+        check_join_lines(
+            r"
+fn foo() {
+    foo(<|>{
+        92
+    })
+}",
+            r"
+fn foo() {
+    foo(<|>92)
+}",
+        );
+    }
+
+    #[test]
+    fn test_join_lines_use_items_left() {
+        // No space after the '{'
+        check_join_lines(
+            r"
+<|>use ra_syntax::{
+    TextUnit, TextRange,
+};",
+            r"
+<|>use ra_syntax::{TextUnit, TextRange,
+};",
+        );
+    }
+
+    #[test]
+    fn test_join_lines_use_items_right() {
+        // No space after the '}'
+        check_join_lines(
+            r"
+use ra_syntax::{
+<|>    TextUnit, TextRange
+};",
+            r"
+use ra_syntax::{
+<|>    TextUnit, TextRange};",
+        );
+    }
+
+    #[test]
+    fn test_join_lines_use_items_right_comma() {
+        // No space after the '}'
+        check_join_lines(
+            r"
+use ra_syntax::{
+<|>    TextUnit, TextRange,
+};",
+            r"
+use ra_syntax::{
+<|>    TextUnit, TextRange};",
+        );
+    }
+
+    #[test]
+    fn test_join_lines_use_tree() {
+        check_join_lines(
+            r"
+use ra_syntax::{
+    algo::<|>{
+        find_leaf_at_offset,
+    },
+    ast,
+};",
+            r"
+use ra_syntax::{
+    algo::<|>find_leaf_at_offset,
+    ast,
+};",
+        );
+    }
+
+    #[test]
+    fn test_join_lines_normal_comments() {
+        check_join_lines(
+            r"
+fn foo() {
+    // Hello<|>
+    // world!
+}
+",
+            r"
+fn foo() {
+    // Hello<|> world!
+}
+",
+        );
+    }
+
+    #[test]
+    fn test_join_lines_doc_comments() {
+        check_join_lines(
+            r"
+fn foo() {
+    /// Hello<|>
+    /// world!
+}
+",
+            r"
+fn foo() {
+    /// Hello<|> world!
+}
+",
+        );
+    }
+
+    #[test]
+    fn test_join_lines_mod_comments() {
+        check_join_lines(
+            r"
+fn foo() {
+    //! Hello<|>
+    //! world!
+}
+",
+            r"
+fn foo() {
+    //! Hello<|> world!
+}
+",
+        );
+    }
+
+    #[test]
+    fn test_join_lines_multiline_comments_1() {
+        check_join_lines(
+            r"
+fn foo() {
+    // Hello<|>
+    /* world! */
+}
+",
+            r"
+fn foo() {
+    // Hello<|> world! */
+}
+",
+        );
+    }
+
+    #[test]
+    fn test_join_lines_multiline_comments_2() {
+        check_join_lines(
+            r"
+fn foo() {
+    // The<|>
+    /* quick
+    brown
+    fox! */
+}
+",
+            r"
+fn foo() {
+    // The<|> quick
+    brown
+    fox! */
+}
+",
+        );
+    }
+
+    fn check_join_lines_sel(before: &str, after: &str) {
+        let (sel, before) = extract_range(before);
+        let file = SourceFile::parse(&before);
+        let result = join_lines(&file, sel);
+        let actual = result.edit.apply(&before);
+        assert_eq_text!(after, &actual);
+    }
+
+    #[test]
+    fn test_join_lines_selection_fn_args() {
+        check_join_lines_sel(
+            r"
+fn foo() {
+    <|>foo(1,
+        2,
+        3,
+    <|>)
+}
+    ",
+            r"
+fn foo() {
+    foo(1, 2, 3)
+}
+    ",
+        );
+    }
+
+    #[test]
+    fn test_join_lines_selection_struct() {
+        check_join_lines_sel(
+            r"
+struct Foo <|>{
+    f: u32,
+}<|>
+    ",
+            r"
+struct Foo { f: u32 }
+    ",
+        );
+    }
+
+    #[test]
+    fn test_join_lines_selection_dot_chain() {
+        check_join_lines_sel(
+            r"
+fn foo() {
+    join(<|>type_params.type_params()
+            .filter_map(|it| it.name())
+            .map(|it| it.text())<|>)
+}",
+            r"
+fn foo() {
+    join(type_params.type_params().filter_map(|it| it.name()).map(|it| it.text()))
+}",
+        );
+    }
+
+    #[test]
+    fn test_join_lines_selection_lambda_block_body() {
+        check_join_lines_sel(
+            r"
+pub fn handle_find_matching_brace() {
+    params.offsets
+        .map(|offset| <|>{
+            world.analysis().matching_brace(&file, offset).unwrap_or(offset)
+        }<|>)
+        .collect();
+}",
+            r"
+pub fn handle_find_matching_brace() {
+    params.offsets
+        .map(|offset| world.analysis().matching_brace(&file, offset).unwrap_or(offset))
+        .collect();
+}",
+        );
+    }
+
+    #[test]
+    fn test_on_eq_typed() {
+        fn do_check(before: &str, after: &str) {
+            let (offset, before) = extract_offset(before);
+            let file = SourceFile::parse(&before);
+            let result = on_eq_typed(&file, offset).unwrap();
+            let actual = result.edit.apply(&before);
+            assert_eq_text!(after, &actual);
+        }
+
+        //     do_check(r"
+        // fn foo() {
+        //     let foo =<|>
+        // }
+        // ", r"
+        // fn foo() {
+        //     let foo =;
+        // }
+        // ");
+        do_check(
+            r"
+fn foo() {
+    let foo =<|> 1 + 1
+}
+",
+            r"
+fn foo() {
+    let foo = 1 + 1;
+}
+",
+        );
+        //     do_check(r"
+        // fn foo() {
+        //     let foo =<|>
+        //     let bar = 1;
+        // }
+        // ", r"
+        // fn foo() {
+        //     let foo =;
+        //     let bar = 1;
+        // }
+        // ");
+    }
+
+    #[test]
+    fn test_on_dot_typed() {
+        fn do_check(before: &str, after: &str) {
+            let (offset, before) = extract_offset(before);
+            let file = SourceFile::parse(&before);
+            if let Some(result) = on_eq_typed(&file, offset) {
+                let actual = result.edit.apply(&before);
+                assert_eq_text!(after, &actual);
+            };
+        }
+        // indent if continuing chain call
+        do_check(
+            r"
+    pub fn child(&self, db: &impl HirDatabase, name: &Name) -> Cancelable<Option<Module>> {
+        self.child_impl(db, name)
+        .<|>
+    }
+",
+            r"
+    pub fn child(&self, db: &impl HirDatabase, name: &Name) -> Cancelable<Option<Module>> {
+        self.child_impl(db, name)
+            .
+    }
+",
+        );
+
+        // do not indent if already indented
+        do_check(
+            r"
+    pub fn child(&self, db: &impl HirDatabase, name: &Name) -> Cancelable<Option<Module>> {
+        self.child_impl(db, name)
+            .<|>
+    }
+",
+            r"
+    pub fn child(&self, db: &impl HirDatabase, name: &Name) -> Cancelable<Option<Module>> {
+        self.child_impl(db, name)
+            .
+    }
+",
+        );
+
+        // indent if the previous line is already indented
+        do_check(
+            r"
+    pub fn child(&self, db: &impl HirDatabase, name: &Name) -> Cancelable<Option<Module>> {
+        self.child_impl(db, name)
+            .first()
+        .<|>
+    }
+",
+            r"
+    pub fn child(&self, db: &impl HirDatabase, name: &Name) -> Cancelable<Option<Module>> {
+        self.child_impl(db, name)
+            .first()
+            .
+    }
+",
+        );
+
+        // don't indent if indent matches previous line
+        do_check(
+            r"
+    pub fn child(&self, db: &impl HirDatabase, name: &Name) -> Cancelable<Option<Module>> {
+        self.child_impl(db, name)
+            .first()
+            .<|>
+    }
+",
+            r"
+    pub fn child(&self, db: &impl HirDatabase, name: &Name) -> Cancelable<Option<Module>> {
+        self.child_impl(db, name)
+            .first()
+            .
+    }
+",
+        );
+
+        // don't indent if there is no method call on previous line
+        do_check(
+            r"
+    pub fn child(&self, db: &impl HirDatabase, name: &Name) -> Cancelable<Option<Module>> {
+        .<|>
+    }
+",
+            r"
+    pub fn child(&self, db: &impl HirDatabase, name: &Name) -> Cancelable<Option<Module>> {
+        .
+    }
+",
+        );
+
+        // indent to match previous expr
+        do_check(
+            r"
+    pub fn child(&self, db: &impl HirDatabase, name: &Name) -> Cancelable<Option<Module>> {
+        self.child_impl(db, name)
+.<|>
+    }
+",
+            r"
+    pub fn child(&self, db: &impl HirDatabase, name: &Name) -> Cancelable<Option<Module>> {
+        self.child_impl(db, name)
+            .
+    }
+",
+        );
+    }
+
+    #[test]
+    fn test_on_enter() {
+        fn apply_on_enter(before: &str) -> Option<String> {
+            let (offset, before) = extract_offset(before);
+            let file = SourceFile::parse(&before);
+            let result = on_enter(&file, offset)?;
+            let actual = result.edit.apply(&before);
+            let actual = add_cursor(&actual, result.cursor_position.unwrap());
+            Some(actual)
+        }
+
+        fn do_check(before: &str, after: &str) {
+            let actual = apply_on_enter(before).unwrap();
+            assert_eq_text!(after, &actual);
+        }
+
+        fn do_check_noop(text: &str) {
+            assert!(apply_on_enter(text).is_none())
+        }
+
+        do_check(
+            r"
+/// Some docs<|>
+fn foo() {
+}
+",
+            r"
+/// Some docs
+/// <|>
+fn foo() {
+}
+",
+        );
+        do_check(
+            r"
+impl S {
+    /// Some<|> docs.
+    fn foo() {}
+}
+",
+            r"
+impl S {
+    /// Some
+    /// <|> docs.
+    fn foo() {}
+}
+",
+        );
+        do_check_noop(r"<|>//! docz");
+    }
+}