Merge #1008

1008: Move extend selection to ra_ide_api r=matklad a=matklad



Co-authored-by: Aleksey Kladov <[email protected]>

7 files changed, 420 insertions, 401 deletions

diff --git a/Cargo.lock b/Cargo.lock
index ad9f6970b..eef6fa621 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -945,6 +945,7 @@ dependencies = [
  "ra_batch 0.1.0",
  "ra_db 0.1.0",
  "ra_hir 0.1.0",
+ "ra_ide_api 0.1.0",
  "ra_ide_api_light 0.1.0",
  "ra_syntax 0.1.0",
  "tools 0.1.0",
diff --git a/crates/ra_cli/Cargo.toml b/crates/ra_cli/Cargo.toml
index ff30bf0b3..4c666f556 100644
--- a/crates/ra_cli/Cargo.toml
+++ b/crates/ra_cli/Cargo.toml
@@ -13,6 +13,7 @@ flexi_logger = "0.11.0"
 indicatif = "0.11.0"
 
 ra_syntax = { path = "../ra_syntax" }
+ra_ide_api = { path = "../ra_ide_api" }
 ra_ide_api_light = { path = "../ra_ide_api_light" }
 tools = { path = "../tools" }
 ra_batch = { path = "../ra_batch" }
diff --git a/crates/ra_cli/src/main.rs b/crates/ra_cli/src/main.rs
index 294f4b8af..5285f1f28 100644
--- a/crates/ra_cli/src/main.rs
+++ b/crates/ra_cli/src/main.rs
@@ -4,7 +4,8 @@ use std::{fs, io::Read, path::Path, time::Instant};
 
 use clap::{App, Arg, SubCommand};
 use join_to_string::join;
-use ra_ide_api_light::{extend_selection, file_structure};
+use ra_ide_api::{Analysis, FileRange};
+use ra_ide_api_light::file_structure;
 use ra_syntax::{SourceFile, TextRange, TreeArc, AstNode};
 use tools::collect_tests;
 use flexi_logger::Logger;
@@ -59,8 +60,8 @@ fn main() -> Result<()> {
         ("extend-selection", Some(matches)) => {
             let start: u32 = matches.value_of("start").unwrap().parse()?;
             let end: u32 = matches.value_of("end").unwrap().parse()?;
-            let file = file()?;
-            let sels = selections(&file, start, end);
+            let text = read_stdin()?;
+            let sels = selections(text, start, end);
             println!("{}", sels)
         }
         ("analysis-stats", Some(matches)) => {
@@ -98,12 +99,17 @@ fn render_test(file: &Path, line: usize) -> Result<(String, String)> {
     Ok((test.text, tree))
 }
 
-fn selections(file: &SourceFile, start: u32, end: u32) -> String {
+fn selections(text: String, start: u32, end: u32) -> String {
+    let (analysis, file_id) = Analysis::from_single_file(text);
     let mut ranges = Vec::new();
-    let mut cur = Some(TextRange::from_to((start - 1).into(), (end - 1).into()));
-    while let Some(r) = cur {
-        ranges.push(r);
-        cur = extend_selection(file.syntax(), r);
+    let mut range = TextRange::from_to((start - 1).into(), (end - 1).into());
+    loop {
+        ranges.push(range);
+        let next = analysis.extend_selection(FileRange { file_id, range }).unwrap();
+        if range == next {
+            break;
+        }
+        range = next;
     }
     let ranges = ranges
         .iter()
diff --git a/crates/ra_ide_api/src/extend_selection.rs b/crates/ra_ide_api/src/extend_selection.rs
index d23290b74..63879a0b5 100644
--- a/crates/ra_ide_api/src/extend_selection.rs
+++ b/crates/ra_ide_api/src/extend_selection.rs
@@ -1,13 +1,378 @@
 use ra_db::SourceDatabase;
-use ra_syntax::AstNode;
-
-use crate::{
-    TextRange, FileRange,
-    db::RootDatabase,
+use ra_syntax::{
+    Direction, SyntaxNode, TextRange, TextUnit, AstNode,
+    algo::{find_covering_node, find_leaf_at_offset, LeafAtOffset},
+    SyntaxKind::*,
 };
 
+use crate::{FileRange, db::RootDatabase};
+
 // FIXME: restore macro support
 pub(crate) fn extend_selection(db: &RootDatabase, frange: FileRange) -> TextRange {
     let source_file = db.parse(frange.file_id);
-    ra_ide_api_light::extend_selection(source_file.syntax(), frange.range).unwrap_or(frange.range)
+    try_extend_selection(source_file.syntax(), frange.range).unwrap_or(frange.range)
+}
+
+fn try_extend_selection(root: &SyntaxNode, range: TextRange) -> Option<TextRange> {
+    let string_kinds = [COMMENT, STRING, RAW_STRING, BYTE_STRING, RAW_BYTE_STRING];
+    let list_kinds = [
+        FIELD_PAT_LIST,
+        MATCH_ARM_LIST,
+        NAMED_FIELD_DEF_LIST,
+        POS_FIELD_DEF_LIST,
+        NAMED_FIELD_LIST,
+        ENUM_VARIANT_LIST,
+        USE_TREE_LIST,
+        TYPE_PARAM_LIST,
+        TYPE_ARG_LIST,
+        PARAM_LIST,
+        ARG_LIST,
+        ARRAY_EXPR,
+    ];
+
+    if range.is_empty() {
+        let offset = range.start();
+        let mut leaves = find_leaf_at_offset(root, offset);
+        if leaves.clone().all(|it| it.kind() == WHITESPACE) {
+            return Some(extend_ws(root, leaves.next()?, offset));
+        }
+        let leaf_range = match leaves {
+            LeafAtOffset::None => return None,
+            LeafAtOffset::Single(l) => {
+                if string_kinds.contains(&l.kind()) {
+                    extend_single_word_in_comment_or_string(l, offset).unwrap_or_else(|| l.range())
+                } else {
+                    l.range()
+                }
+            }
+            LeafAtOffset::Between(l, r) => pick_best(l, r).range(),
+        };
+        return Some(leaf_range);
+    };
+    let node = find_covering_node(root, range);
+
+    // Using shallowest node with same range allows us to traverse siblings.
+    let node = node.ancestors().take_while(|n| n.range() == node.range()).last().unwrap();
+
+    if range == node.range() {
+        if string_kinds.contains(&node.kind()) {
+            if let Some(range) = extend_comments(node) {
+                return Some(range);
+            }
+        }
+
+        if node.parent().map(|n| list_kinds.contains(&n.kind())) == Some(true) {
+            if let Some(range) = extend_list_item(node) {
+                return Some(range);
+            }
+        }
+    }
+
+    match node.ancestors().skip_while(|n| n.range() == range).next() {
+        None => None,
+        Some(parent) => Some(parent.range()),
+    }
+}
+
+fn extend_single_word_in_comment_or_string(
+    leaf: &SyntaxNode,
+    offset: TextUnit,
+) -> Option<TextRange> {
+    let text: &str = leaf.leaf_text()?;
+    let cursor_position: u32 = (offset - leaf.range().start()).into();
+
+    let (before, after) = text.split_at(cursor_position as usize);
+
+    fn non_word_char(c: char) -> bool {
+        !(c.is_alphanumeric() || c == '_')
+    }
+
+    let start_idx = before.rfind(non_word_char)? as u32;
+    let end_idx = after.find(non_word_char).unwrap_or(after.len()) as u32;
+
+    let from: TextUnit = (start_idx + 1).into();
+    let to: TextUnit = (cursor_position + end_idx).into();
+
+    let range = TextRange::from_to(from, to);
+    if range.is_empty() {
+        None
+    } else {
+        Some(range + leaf.range().start())
+    }
+}
+
+fn extend_ws(root: &SyntaxNode, ws: &SyntaxNode, offset: TextUnit) -> TextRange {
+    let ws_text = ws.leaf_text().unwrap();
+    let suffix = TextRange::from_to(offset, ws.range().end()) - ws.range().start();
+    let prefix = TextRange::from_to(ws.range().start(), offset) - ws.range().start();
+    let ws_suffix = &ws_text.as_str()[suffix];
+    let ws_prefix = &ws_text.as_str()[prefix];
+    if ws_text.contains('\n') && !ws_suffix.contains('\n') {
+        if let Some(node) = ws.next_sibling() {
+            let start = match ws_prefix.rfind('\n') {
+                Some(idx) => ws.range().start() + TextUnit::from((idx + 1) as u32),
+                None => node.range().start(),
+            };
+            let end = if root.text().char_at(node.range().end()) == Some('\n') {
+                node.range().end() + TextUnit::of_char('\n')
+            } else {
+                node.range().end()
+            };
+            return TextRange::from_to(start, end);
+        }
+    }
+    ws.range()
+}
+
+fn pick_best<'a>(l: &'a SyntaxNode, r: &'a SyntaxNode) -> &'a SyntaxNode {
+    return if priority(r) > priority(l) { r } else { l };
+    fn priority(n: &SyntaxNode) -> usize {
+        match n.kind() {
+            WHITESPACE => 0,
+            IDENT | SELF_KW | SUPER_KW | CRATE_KW | LIFETIME => 2,
+            _ => 1,
+        }
+    }
+}
+
+/// Extend list item selection to include nearby comma and whitespace.
+fn extend_list_item(node: &SyntaxNode) -> Option<TextRange> {
+    fn is_single_line_ws(node: &SyntaxNode) -> bool {
+        node.kind() == WHITESPACE && !node.leaf_text().unwrap().contains('\n')
+    }
+
+    fn nearby_comma(node: &SyntaxNode, dir: Direction) -> Option<&SyntaxNode> {
+        node.siblings(dir)
+            .skip(1)
+            .skip_while(|node| is_single_line_ws(node))
+            .next()
+            .filter(|node| node.kind() == COMMA)
+    }
+
+    if let Some(comma_node) = nearby_comma(node, Direction::Prev) {
+        return Some(TextRange::from_to(comma_node.range().start(), node.range().end()));
+    }
+
+    if let Some(comma_node) = nearby_comma(node, Direction::Next) {
+        // Include any following whitespace when comma if after list item.
+        let final_node = comma_node
+            .siblings(Direction::Next)
+            .skip(1)
+            .next()
+            .filter(|node| is_single_line_ws(node))
+            .unwrap_or(comma_node);
+
+        return Some(TextRange::from_to(node.range().start(), final_node.range().end()));
+    }
+
+    return None;
+}
+
+fn extend_comments(node: &SyntaxNode) -> Option<TextRange> {
+    let prev = adj_comments(node, Direction::Prev);
+    let next = adj_comments(node, Direction::Next);
+    if prev != next {
+        Some(TextRange::from_to(prev.range().start(), next.range().end()))
+    } else {
+        None
+    }
+}
+
+fn adj_comments(node: &SyntaxNode, dir: Direction) -> &SyntaxNode {
+    let mut res = node;
+    for node in node.siblings(dir) {
+        match node.kind() {
+            COMMENT => res = node,
+            WHITESPACE if !node.leaf_text().unwrap().as_str().contains("\n\n") => (),
+            _ => break,
+        }
+    }
+    res
+}
+
+#[cfg(test)]
+mod tests {
+    use ra_syntax::{SourceFile, AstNode};
+    use test_utils::extract_offset;
+
+    use super::*;
+
+    fn do_check(before: &str, afters: &[&str]) {
+        let (cursor, before) = extract_offset(before);
+        let file = SourceFile::parse(&before);
+        let mut range = TextRange::offset_len(cursor, 0.into());
+        for &after in afters {
+            range = try_extend_selection(file.syntax(), range).unwrap();
+            let actual = &before[range];
+            assert_eq!(after, actual);
+        }
+    }
+
+    #[test]
+    fn test_extend_selection_arith() {
+        do_check(r#"fn foo() { <|>1 + 1 }"#, &["1", "1 + 1", "{ 1 + 1 }"]);
+    }
+
+    #[test]
+    fn test_extend_selection_list() {
+        do_check(r#"fn foo(<|>x: i32) {}"#, &["x", "x: i32"]);
+        do_check(r#"fn foo(<|>x: i32, y: i32) {}"#, &["x", "x: i32", "x: i32, "]);
+        do_check(r#"fn foo(<|>x: i32,y: i32) {}"#, &["x", "x: i32", "x: i32,"]);
+        do_check(r#"fn foo(x: i32, <|>y: i32) {}"#, &["y", "y: i32", ", y: i32"]);
+        do_check(r#"fn foo(x: i32, <|>y: i32, ) {}"#, &["y", "y: i32", ", y: i32"]);
+        do_check(r#"fn foo(x: i32,<|>y: i32) {}"#, &["y", "y: i32", ",y: i32"]);
+
+        do_check(r#"const FOO: [usize; 2] = [ 22<|> , 33];"#, &["22", "22 , "]);
+        do_check(r#"const FOO: [usize; 2] = [ 22 , 33<|>];"#, &["33", ", 33"]);
+        do_check(r#"const FOO: [usize; 2] = [ 22 , 33<|> ,];"#, &["33", ", 33"]);
+
+        do_check(
+            r#"
+const FOO: [usize; 2] = [
+    22,
+    <|>33,
+]"#,
+            &["33", "33,"],
+        );
+
+        do_check(
+            r#"
+const FOO: [usize; 2] = [
+    22
+    , 33<|>,
+]"#,
+            &["33", ", 33"],
+        );
+    }
+
+    #[test]
+    fn test_extend_selection_start_of_the_line() {
+        do_check(
+            r#"
+impl S {
+<|>    fn foo() {
+
+    }
+}"#,
+            &["    fn foo() {\n\n    }\n"],
+        );
+    }
+
+    #[test]
+    fn test_extend_selection_doc_comments() {
+        do_check(
+            r#"
+struct A;
+
+/// bla
+/// bla
+struct B {
+    <|>
+}
+            "#,
+            &["\n    \n", "{\n    \n}", "/// bla\n/// bla\nstruct B {\n    \n}"],
+        )
+    }
+
+    #[test]
+    fn test_extend_selection_comments() {
+        do_check(
+            r#"
+fn bar(){}
+
+// fn foo() {
+// 1 + <|>1
+// }
+
+// fn foo(){}
+    "#,
+            &["1", "// 1 + 1", "// fn foo() {\n// 1 + 1\n// }"],
+        );
+
+        do_check(
+            r#"
+// #[derive(Debug, Clone, Copy, PartialEq, Eq)]
+// pub enum Direction {
+//  <|>   Next,
+//     Prev
+// }
+"#,
+            &[
+                "//     Next,",
+                "// #[derive(Debug, Clone, Copy, PartialEq, Eq)]\n// pub enum Direction {\n//     Next,\n//     Prev\n// }",
+            ],
+        );
+
+        do_check(
+            r#"
+/*
+foo
+_bar1<|>*/
+    "#,
+            &["_bar1", "/*\nfoo\n_bar1*/"],
+        );
+
+        do_check(
+            r#"
+//!<|>foo_2 bar
+    "#,
+            &["foo_2", "//!foo_2 bar"],
+        );
+
+        do_check(
+            r#"
+/<|>/foo bar
+    "#,
+            &["//foo bar"],
+        );
+    }
+
+    #[test]
+    fn test_extend_selection_prefer_idents() {
+        do_check(
+            r#"
+fn main() { foo<|>+bar;}
+    "#,
+            &["foo", "foo+bar"],
+        );
+        do_check(
+            r#"
+fn main() { foo+<|>bar;}
+    "#,
+            &["bar", "foo+bar"],
+        );
+    }
+
+    #[test]
+    fn test_extend_selection_prefer_lifetimes() {
+        do_check(r#"fn foo<<|>'a>() {}"#, &["'a", "<'a>"]);
+        do_check(r#"fn foo<'a<|>>() {}"#, &["'a", "<'a>"]);
+    }
+
+    #[test]
+    fn test_extend_selection_select_first_word() {
+        do_check(r#"// foo bar b<|>az quxx"#, &["baz", "// foo bar baz quxx"]);
+        do_check(
+            r#"
+impl S {
+    fn foo() {
+        // hel<|>lo world
+    }
+}
+        "#,
+            &["hello", "// hello world"],
+        );
+    }
+
+    #[test]
+    fn test_extend_selection_string() {
+        do_check(
+            r#"
+fn bar(){}
+
+" fn f<|>oo() {"
+    "#,
+            &["foo", "\" fn foo() {\""],
+        );
+    }
 }
diff --git a/crates/ra_ide_api/src/lib.rs b/crates/ra_ide_api/src/lib.rs
index b8a4adbce..81ca57035 100644
--- a/crates/ra_ide_api/src/lib.rs
+++ b/crates/ra_ide_api/src/lib.rs
@@ -211,6 +211,23 @@ pub struct Analysis {
 // API, the API should in theory be usable as a library, or via a different
 // protocol.
 impl Analysis {
+    // Creates an analysis instance for a single file, without any extenal
+    // dependencies, stdlib support or ability to apply changes. See
+    // `AnalysisHost` for creating a fully-featured analysis.
+    pub fn from_single_file(text: String) -> (Analysis, FileId) {
+        let mut host = AnalysisHost::default();
+        let source_root = SourceRootId(0);
+        let mut change = AnalysisChange::new();
+        change.add_root(source_root, true);
+        let mut crate_graph = CrateGraph::default();
+        let file_id = FileId(0);
+        crate_graph.add_crate_root(file_id, Edition::Edition2018);
+        change.add_file(source_root, file_id, "main.rs".into(), Arc::new(text));
+        change.set_crate_graph(crate_graph);
+        host.apply_change(change);
+        (host.analysis(), file_id)
+    }
+
     /// Debug info about the current state of the analysis
     pub fn status(&self) -> String {
         status::status(&*self.db)
diff --git a/crates/ra_ide_api_light/src/extend_selection.rs b/crates/ra_ide_api_light/src/extend_selection.rs
deleted file mode 100644
index 28d62f290..000000000
--- a/crates/ra_ide_api_light/src/extend_selection.rs
+++ /dev/null
@@ -1,369 +0,0 @@
-use ra_syntax::{
-    Direction, SyntaxNode, TextRange, TextUnit,
-    algo::{find_covering_node, find_leaf_at_offset, LeafAtOffset},
-    SyntaxKind::*,
-};
-
-pub fn extend_selection(root: &SyntaxNode, range: TextRange) -> Option<TextRange> {
-    let string_kinds = [COMMENT, STRING, RAW_STRING, BYTE_STRING, RAW_BYTE_STRING];
-    let list_kinds = [
-        FIELD_PAT_LIST,
-        MATCH_ARM_LIST,
-        NAMED_FIELD_DEF_LIST,
-        POS_FIELD_DEF_LIST,
-        NAMED_FIELD_LIST,
-        ENUM_VARIANT_LIST,
-        USE_TREE_LIST,
-        TYPE_PARAM_LIST,
-        TYPE_ARG_LIST,
-        PARAM_LIST,
-        ARG_LIST,
-        ARRAY_EXPR,
-    ];
-
-    if range.is_empty() {
-        let offset = range.start();
-        let mut leaves = find_leaf_at_offset(root, offset);
-        if leaves.clone().all(|it| it.kind() == WHITESPACE) {
-            return Some(extend_ws(root, leaves.next()?, offset));
-        }
-        let leaf_range = match leaves {
-            LeafAtOffset::None => return None,
-            LeafAtOffset::Single(l) => {
-                if string_kinds.contains(&l.kind()) {
-                    extend_single_word_in_comment_or_string(l, offset).unwrap_or_else(|| l.range())
-                } else {
-                    l.range()
-                }
-            }
-            LeafAtOffset::Between(l, r) => pick_best(l, r).range(),
-        };
-        return Some(leaf_range);
-    };
-    let node = find_covering_node(root, range);
-
-    // Using shallowest node with same range allows us to traverse siblings.
-    let node = node.ancestors().take_while(|n| n.range() == node.range()).last().unwrap();
-
-    if range == node.range() {
-        if string_kinds.contains(&node.kind()) {
-            if let Some(range) = extend_comments(node) {
-                return Some(range);
-            }
-        }
-
-        if node.parent().map(|n| list_kinds.contains(&n.kind())) == Some(true) {
-            if let Some(range) = extend_list_item(node) {
-                return Some(range);
-            }
-        }
-    }
-
-    match node.ancestors().skip_while(|n| n.range() == range).next() {
-        None => None,
-        Some(parent) => Some(parent.range()),
-    }
-}
-
-fn extend_single_word_in_comment_or_string(
-    leaf: &SyntaxNode,
-    offset: TextUnit,
-) -> Option<TextRange> {
-    let text: &str = leaf.leaf_text()?;
-    let cursor_position: u32 = (offset - leaf.range().start()).into();
-
-    let (before, after) = text.split_at(cursor_position as usize);
-
-    fn non_word_char(c: char) -> bool {
-        !(c.is_alphanumeric() || c == '_')
-    }
-
-    let start_idx = before.rfind(non_word_char)? as u32;
-    let end_idx = after.find(non_word_char).unwrap_or(after.len()) as u32;
-
-    let from: TextUnit = (start_idx + 1).into();
-    let to: TextUnit = (cursor_position + end_idx).into();
-
-    let range = TextRange::from_to(from, to);
-    if range.is_empty() {
-        None
-    } else {
-        Some(range + leaf.range().start())
-    }
-}
-
-fn extend_ws(root: &SyntaxNode, ws: &SyntaxNode, offset: TextUnit) -> TextRange {
-    let ws_text = ws.leaf_text().unwrap();
-    let suffix = TextRange::from_to(offset, ws.range().end()) - ws.range().start();
-    let prefix = TextRange::from_to(ws.range().start(), offset) - ws.range().start();
-    let ws_suffix = &ws_text.as_str()[suffix];
-    let ws_prefix = &ws_text.as_str()[prefix];
-    if ws_text.contains('\n') && !ws_suffix.contains('\n') {
-        if let Some(node) = ws.next_sibling() {
-            let start = match ws_prefix.rfind('\n') {
-                Some(idx) => ws.range().start() + TextUnit::from((idx + 1) as u32),
-                None => node.range().start(),
-            };
-            let end = if root.text().char_at(node.range().end()) == Some('\n') {
-                node.range().end() + TextUnit::of_char('\n')
-            } else {
-                node.range().end()
-            };
-            return TextRange::from_to(start, end);
-        }
-    }
-    ws.range()
-}
-
-fn pick_best<'a>(l: &'a SyntaxNode, r: &'a SyntaxNode) -> &'a SyntaxNode {
-    return if priority(r) > priority(l) { r } else { l };
-    fn priority(n: &SyntaxNode) -> usize {
-        match n.kind() {
-            WHITESPACE => 0,
-            IDENT | SELF_KW | SUPER_KW | CRATE_KW | LIFETIME => 2,
-            _ => 1,
-        }
-    }
-}
-
-/// Extend list item selection to include nearby comma and whitespace.
-fn extend_list_item(node: &SyntaxNode) -> Option<TextRange> {
-    fn is_single_line_ws(node: &SyntaxNode) -> bool {
-        node.kind() == WHITESPACE && !node.leaf_text().unwrap().contains('\n')
-    }
-
-    fn nearby_comma(node: &SyntaxNode, dir: Direction) -> Option<&SyntaxNode> {
-        node.siblings(dir)
-            .skip(1)
-            .skip_while(|node| is_single_line_ws(node))
-            .next()
-            .filter(|node| node.kind() == COMMA)
-    }
-
-    if let Some(comma_node) = nearby_comma(node, Direction::Prev) {
-        return Some(TextRange::from_to(comma_node.range().start(), node.range().end()));
-    }
-
-    if let Some(comma_node) = nearby_comma(node, Direction::Next) {
-        // Include any following whitespace when comma if after list item.
-        let final_node = comma_node
-            .siblings(Direction::Next)
-            .skip(1)
-            .next()
-            .filter(|node| is_single_line_ws(node))
-            .unwrap_or(comma_node);
-
-        return Some(TextRange::from_to(node.range().start(), final_node.range().end()));
-    }
-
-    return None;
-}
-
-fn extend_comments(node: &SyntaxNode) -> Option<TextRange> {
-    let prev = adj_comments(node, Direction::Prev);
-    let next = adj_comments(node, Direction::Next);
-    if prev != next {
-        Some(TextRange::from_to(prev.range().start(), next.range().end()))
-    } else {
-        None
-    }
-}
-
-fn adj_comments(node: &SyntaxNode, dir: Direction) -> &SyntaxNode {
-    let mut res = node;
-    for node in node.siblings(dir) {
-        match node.kind() {
-            COMMENT => res = node,
-            WHITESPACE if !node.leaf_text().unwrap().as_str().contains("\n\n") => (),
-            _ => break,
-        }
-    }
-    res
-}
-
-#[cfg(test)]
-mod tests {
-    use ra_syntax::{SourceFile, AstNode};
-    use test_utils::extract_offset;
-
-    use super::*;
-
-    fn do_check(before: &str, afters: &[&str]) {
-        let (cursor, before) = extract_offset(before);
-        let file = SourceFile::parse(&before);
-        let mut range = TextRange::offset_len(cursor, 0.into());
-        for &after in afters {
-            range = extend_selection(file.syntax(), range).unwrap();
-            let actual = &before[range];
-            assert_eq!(after, actual);
-        }
-    }
-
-    #[test]
-    fn test_extend_selection_arith() {
-        do_check(r#"fn foo() { <|>1 + 1 }"#, &["1", "1 + 1", "{ 1 + 1 }"]);
-    }
-
-    #[test]
-    fn test_extend_selection_list() {
-        do_check(r#"fn foo(<|>x: i32) {}"#, &["x", "x: i32"]);
-        do_check(r#"fn foo(<|>x: i32, y: i32) {}"#, &["x", "x: i32", "x: i32, "]);
-        do_check(r#"fn foo(<|>x: i32,y: i32) {}"#, &["x", "x: i32", "x: i32,"]);
-        do_check(r#"fn foo(x: i32, <|>y: i32) {}"#, &["y", "y: i32", ", y: i32"]);
-        do_check(r#"fn foo(x: i32, <|>y: i32, ) {}"#, &["y", "y: i32", ", y: i32"]);
-        do_check(r#"fn foo(x: i32,<|>y: i32) {}"#, &["y", "y: i32", ",y: i32"]);
-
-        do_check(r#"const FOO: [usize; 2] = [ 22<|> , 33];"#, &["22", "22 , "]);
-        do_check(r#"const FOO: [usize; 2] = [ 22 , 33<|>];"#, &["33", ", 33"]);
-        do_check(r#"const FOO: [usize; 2] = [ 22 , 33<|> ,];"#, &["33", ", 33"]);
-
-        do_check(
-            r#"
-const FOO: [usize; 2] = [
-    22,
-    <|>33,
-]"#,
-            &["33", "33,"],
-        );
-
-        do_check(
-            r#"
-const FOO: [usize; 2] = [
-    22
-    , 33<|>,
-]"#,
-            &["33", ", 33"],
-        );
-    }
-
-    #[test]
-    fn test_extend_selection_start_of_the_line() {
-        do_check(
-            r#"
-impl S {
-<|>    fn foo() {
-
-    }
-}"#,
-            &["    fn foo() {\n\n    }\n"],
-        );
-    }
-
-    #[test]
-    fn test_extend_selection_doc_comments() {
-        do_check(
-            r#"
-struct A;
-
-/// bla
-/// bla
-struct B {
-    <|>
-}
-            "#,
-            &["\n    \n", "{\n    \n}", "/// bla\n/// bla\nstruct B {\n    \n}"],
-        )
-    }
-
-    #[test]
-    fn test_extend_selection_comments() {
-        do_check(
-            r#"
-fn bar(){}
-
-// fn foo() {
-// 1 + <|>1
-// }
-
-// fn foo(){}
-    "#,
-            &["1", "// 1 + 1", "// fn foo() {\n// 1 + 1\n// }"],
-        );
-
-        do_check(
-            r#"
-// #[derive(Debug, Clone, Copy, PartialEq, Eq)]
-// pub enum Direction {
-//  <|>   Next,
-//     Prev
-// }
-"#,
-            &[
-                "//     Next,",
-                "// #[derive(Debug, Clone, Copy, PartialEq, Eq)]\n// pub enum Direction {\n//     Next,\n//     Prev\n// }",
-            ],
-        );
-
-        do_check(
-            r#"
-/*
-foo
-_bar1<|>*/
-    "#,
-            &["_bar1", "/*\nfoo\n_bar1*/"],
-        );
-
-        do_check(
-            r#"
-//!<|>foo_2 bar
-    "#,
-            &["foo_2", "//!foo_2 bar"],
-        );
-
-        do_check(
-            r#"
-/<|>/foo bar
-    "#,
-            &["//foo bar"],
-        );
-    }
-
-    #[test]
-    fn test_extend_selection_prefer_idents() {
-        do_check(
-            r#"
-fn main() { foo<|>+bar;}
-    "#,
-            &["foo", "foo+bar"],
-        );
-        do_check(
-            r#"
-fn main() { foo+<|>bar;}
-    "#,
-            &["bar", "foo+bar"],
-        );
-    }
-
-    #[test]
-    fn test_extend_selection_prefer_lifetimes() {
-        do_check(r#"fn foo<<|>'a>() {}"#, &["'a", "<'a>"]);
-        do_check(r#"fn foo<'a<|>>() {}"#, &["'a", "<'a>"]);
-    }
-
-    #[test]
-    fn test_extend_selection_select_first_word() {
-        do_check(r#"// foo bar b<|>az quxx"#, &["baz", "// foo bar baz quxx"]);
-        do_check(
-            r#"
-impl S {
-    fn foo() {
-        // hel<|>lo world
-    }
-}
-        "#,
-            &["hello", "// hello world"],
-        );
-    }
-
-    #[test]
-    fn test_extend_selection_string() {
-        do_check(
-            r#"
-fn bar(){}
-
-" fn f<|>oo() {"
-    "#,
-            &["foo", "\" fn foo() {\""],
-        );
-    }
-}
diff --git a/crates/ra_ide_api_light/src/lib.rs b/crates/ra_ide_api_light/src/lib.rs
index 43cdd6ea4..ca13eb018 100644
--- a/crates/ra_ide_api_light/src/lib.rs
+++ b/crates/ra_ide_api_light/src/lib.rs
@@ -3,7 +3,6 @@
 //! This usually means functions which take syntax tree as an input and produce
 //! an edit or some auxiliary info.
 
-mod extend_selection;
 mod folding_ranges;
 mod line_index;
 mod line_index_utils;
@@ -14,15 +13,16 @@ mod join_lines;
 mod typing;
 mod diagnostics;
 
-#[derive(Debug)]
-pub struct LocalEdit {
-    pub label: String,
-    pub edit: ra_text_edit::TextEdit,
-    pub cursor_position: Option<TextUnit>,
-}
+use rustc_hash::FxHashSet;
+use ra_text_edit::TextEditBuilder;
+use ra_syntax::{
+    SourceFile, SyntaxNode, TextRange, TextUnit, Direction,
+    algo::find_leaf_at_offset,
+    SyntaxKind::{self, *},
+    ast::{self, AstNode},
+};
 
-pub use self::{
-    extend_selection::extend_selection,
+pub use crate::{
     folding_ranges::{folding_ranges, Fold, FoldKind},
     line_index::{LineCol, LineIndex},
     line_index_utils::translate_offset_with_edit,
@@ -30,16 +30,14 @@ pub use self::{
     diagnostics::diagnostics,
     join_lines::join_lines,
     typing::{on_enter, on_dot_typed, on_eq_typed},
-
 };
-use ra_text_edit::TextEditBuilder;
-use ra_syntax::{
-    SourceFile, SyntaxNode, TextRange, TextUnit, Direction,
-    SyntaxKind::{self, *},
-    ast::{self, AstNode},
-    algo::find_leaf_at_offset,
-};
-use rustc_hash::FxHashSet;
+
+#[derive(Debug)]
+pub struct LocalEdit {
+    pub label: String,
+    pub edit: ra_text_edit::TextEdit,
+    pub cursor_position: Option<TextUnit>,
+}
 
 #[derive(Debug)]
 pub struct HighlightedRange {