Add some assist ranges

5 files changed, 58 insertions, 10 deletions

diff --git a/crates/ra_assists/src/add_derive.rs b/crates/ra_assists/src/add_derive.rs
index caf21e079..de33b356c 100644
--- a/crates/ra_assists/src/add_derive.rs
+++ b/crates/ra_assists/src/add_derive.rs
@@ -24,6 +24,7 @@ pub(crate) fn add_derive(ctx: AssistCtx<impl HirDatabase>) -> Option<Assist> {
             }
             Some(tt) => tt.syntax().range().end() - TextUnit::of_char(')'),
         };
+        edit.target(nominal.syntax().range());
         edit.set_cursor(offset)
     })
 }
diff --git a/crates/ra_assists/src/assist_ctx.rs b/crates/ra_assists/src/assist_ctx.rs
index 0bf640241..41c8ac2f6 100644
--- a/crates/ra_assists/src/assist_ctx.rs
+++ b/crates/ra_assists/src/assist_ctx.rs
@@ -16,7 +16,7 @@ pub(crate) enum Assist {
 
 /// `AssistCtx` allows to apply an assist or check if it could be applied.
 ///
-/// Assists use a somewhat overengineered approach, given the current needs. The
+/// Assists use a somewhat over-engineered approach, given the current needs. The
 /// assists workflow consists of two phases. In the first phase, a user asks for
 /// the list of available assists. In the second phase, the user picks a
 /// particular assist and it gets applied.
@@ -106,6 +106,7 @@ impl<'a, DB: HirDatabase> AssistCtx<'a, DB> {
 pub(crate) struct AssistBuilder {
     edit: TextEditBuilder,
     cursor_position: Option<TextUnit>,
+    target: Option<TextRange>,
 }
 
 impl AssistBuilder {
@@ -138,7 +139,15 @@ impl AssistBuilder {
         self.cursor_position = Some(offset)
     }
 
+    pub(crate) fn target(&mut self, target: TextRange) {
+        self.target = Some(target)
+    }
+
     fn build(self) -> AssistAction {
-        AssistAction { edit: self.edit.finish(), cursor_position: self.cursor_position }
+        AssistAction {
+            edit: self.edit.finish(),
+            cursor_position: self.cursor_position,
+            target: self.target,
+        }
     }
 }
diff --git a/crates/ra_assists/src/change_visibility.rs b/crates/ra_assists/src/change_visibility.rs
index fa5f231c8..73dd8319f 100644
--- a/crates/ra_assists/src/change_visibility.rs
+++ b/crates/ra_assists/src/change_visibility.rs
@@ -20,7 +20,7 @@ fn add_vis(ctx: AssistCtx<impl HirDatabase>) -> Option<Assist> {
         _ => false,
     });
 
-    let offset = if let Some(keyword) = item_keyword {
+    let (offset, target) = if let Some(keyword) = item_keyword {
         let parent = keyword.parent()?;
         let def_kws = vec![FN_DEF, MODULE, STRUCT_DEF, ENUM_DEF, TRAIT_DEF];
         // Parent is not a definition, can't add visibility
@@ -31,17 +31,18 @@ fn add_vis(ctx: AssistCtx<impl HirDatabase>) -> Option<Assist> {
         if parent.children().any(|child| child.kind() == VISIBILITY) {
             return None;
         }
-        vis_offset(parent)
+        (vis_offset(parent), parent.range())
     } else {
         let ident = ctx.leaf_at_offset().find(|leaf| leaf.kind() == IDENT)?;
         let field = ident.ancestors().find_map(ast::NamedFieldDef::cast)?;
         if field.name()?.syntax().range() != ident.range() && field.visibility().is_some() {
             return None;
         }
-        vis_offset(field.syntax())
+        (vis_offset(field.syntax()), field.syntax().range())
     };
 
     ctx.build("make pub(crate)", |edit| {
+        edit.target(target);
         edit.insert(offset, "pub(crate) ");
         edit.set_cursor(offset);
     })
@@ -60,13 +61,15 @@ fn vis_offset(node: &SyntaxNode) -> TextUnit {
 
 fn change_vis(ctx: AssistCtx<impl HirDatabase>, vis: &ast::Visibility) -> Option<Assist> {
     if vis.syntax().text() == "pub" {
-        return ctx.build("chage to pub(crate)", |edit| {
+        return ctx.build("change to pub(crate)", |edit| {
+            edit.target(vis.syntax().range());
             edit.replace(vis.syntax().range(), "pub(crate)");
             edit.set_cursor(vis.syntax().range().start());
         });
     }
     if vis.syntax().text() == "pub(crate)" {
-        return ctx.build("chage to pub", |edit| {
+        return ctx.build("change to pub", |edit| {
+            edit.target(vis.syntax().range());
             edit.replace(vis.syntax().range(), "pub");
             edit.set_cursor(vis.syntax().range().start());
         });
diff --git a/crates/ra_assists/src/lib.rs b/crates/ra_assists/src/lib.rs
index 881db6347..fc4e95303 100644
--- a/crates/ra_assists/src/lib.rs
+++ b/crates/ra_assists/src/lib.rs
@@ -8,7 +8,7 @@
 mod assist_ctx;
 
 use ra_text_edit::TextEdit;
-use ra_syntax::{TextUnit, SyntaxNode, Direction};
+use ra_syntax::{TextRange, TextUnit, SyntaxNode, Direction};
 use ra_db::FileRange;
 use hir::db::HirDatabase;
 
@@ -23,6 +23,7 @@ pub struct AssistLabel {
 pub struct AssistAction {
     pub edit: TextEdit,
     pub cursor_position: Option<TextUnit>,
+    pub target: Option<TextRange>,
 }
 
 /// Return all the assists applicable at the given position.
@@ -53,15 +54,26 @@ pub fn assists<H>(db: &H, range: FileRange) -> Vec<(AssistLabel, AssistAction)>
 where
     H: HirDatabase + 'static,
 {
+    use std::cmp::Ordering;
+
     AssistCtx::with_ctx(db, range, true, |ctx| {
-        all_assists()
+        let mut a = all_assists()
             .iter()
             .filter_map(|f| f(ctx.clone()))
             .map(|a| match a {
                 Assist::Resolved(label, action) => (label, action),
                 Assist::Unresolved(..) => unreachable!(),
             })
-            .collect()
+            .collect::<Vec<(AssistLabel, AssistAction)>>();
+        a.sort_unstable_by(|a, b| match a {
+            // Some(y) < Some(x) < None for y < x
+            (_, AssistAction { target: Some(a), .. }) => match b {
+                (_, AssistAction { target: Some(b), .. }) => a.len().cmp(&b.len()),
+                _ => Ordering::Less,
+            },
+            _ => Ordering::Greater,
+        });
+        a
     })
 }
 
@@ -162,5 +174,27 @@ mod helpers {
         let assist = AssistCtx::with_ctx(&db, frange, true, assist);
         assert!(assist.is_none());
     }
+}
+
+#[cfg(test)]
+mod tests {
+    use hir::mock::MockDatabase;
+    use ra_syntax::TextRange;
+    use ra_db::FileRange;
+    use test_utils::extract_offset;
+
+    #[test]
+    fn assist_order() {
+        let before = "struct Foo { <|>bar: u32 }";
+        let (before_cursor_pos, before) = extract_offset(before);
+        let (db, _source_root, file_id) = MockDatabase::with_single_file(&before);
+        let frange =
+            FileRange { file_id, range: TextRange::offset_len(before_cursor_pos, 0.into()) };
+        let assists = super::assists(&db, frange);
+        let mut assists = assists.iter();
+
+        assert_eq!(assists.next().expect("expected assist").0.label, "make pub(crate)");
+        assert_eq!(assists.next().expect("expected assist").0.label, "add `#[derive]`");
+    }
 
 }
diff --git a/crates/ra_assists/src/split_import.rs b/crates/ra_assists/src/split_import.rs
index fb69cef9c..287c05830 100644
--- a/crates/ra_assists/src/split_import.rs
+++ b/crates/ra_assists/src/split_import.rs
@@ -24,6 +24,7 @@ pub(crate) fn split_import(ctx: AssistCtx<impl HirDatabase>) -> Option<Assist> {
     };
 
     ctx.build("split import", |edit| {
+        edit.target(colon_colon.range());
         edit.insert(l_curly, "{");
         edit.insert(r_curly, "}");
         edit.set_cursor(l_curly + TextUnit::of_str("{"));