Finish hiding doc.state / State as an implementation detail.

5 files changed, 174 insertions, 145 deletions

diff --git a/helix-core/src/movement.rs b/helix-core/src/movement.rs
index 57abc498..88d6df0a 100644
--- a/helix-core/src/movement.rs
+++ b/helix-core/src/movement.rs
@@ -1,6 +1,66 @@
 use crate::graphemes::{nth_next_grapheme_boundary, nth_prev_grapheme_boundary, RopeGraphemes};
 use crate::{coords_at_pos, pos_at_coords, ChangeSet, Position, Range, Rope, RopeSlice, Selection};
 
+#[derive(Copy, Clone, PartialEq, Eq)]
+pub enum Direction {
+    Forward,
+    Backward,
+}
+
+pub fn move_horizontally(
+    text: RopeSlice,
+    range: Range,
+    dir: Direction,
+    count: usize,
+    extend: bool,
+) -> Range {
+    let pos = range.head;
+    let line = text.char_to_line(pos);
+    // TODO: we can optimize clamping by passing in RopeSlice limited to current line. that way
+    // we stop calculating past start/end of line.
+    let pos = match dir {
+        Direction::Backward => {
+            let start = text.line_to_char(line);
+            nth_prev_grapheme_boundary(text, pos, count).max(start)
+        }
+        Direction::Forward => {
+            // Line end is pos at the start of next line - 1
+            // subtract another 1 because the line ends with \n
+            let end = text.line_to_char(line + 1).saturating_sub(2);
+            nth_next_grapheme_boundary(text, pos, count).min(end)
+        }
+    };
+    Range::new(if extend { range.anchor } else { pos }, pos)
+}
+
+pub fn move_vertically(
+    text: RopeSlice,
+    range: Range,
+    dir: Direction,
+    count: usize,
+    extend: bool,
+) -> Range {
+    let Position { row, col } = coords_at_pos(text, range.head);
+
+    let horiz = range.horiz.unwrap_or(col as u32);
+
+    let new_line = match dir {
+        Direction::Backward => row.saturating_sub(count),
+        Direction::Forward => std::cmp::min(row.saturating_add(count), text.len_lines() - 1),
+    };
+
+    // convert to 0-indexed, subtract another 1 because len_chars() counts \n
+    let new_line_len = text.line(new_line).len_chars().saturating_sub(2);
+
+    let new_col = std::cmp::min(horiz as usize, new_line_len);
+
+    let pos = pos_at_coords(text, Position::new(new_line, new_col));
+
+    let mut range = Range::new(if extend { range.anchor } else { pos }, pos);
+    range.horiz = Some(horiz);
+    range
+}
+
 pub fn move_next_word_start(slice: RopeSlice, mut pos: usize, count: usize) -> usize {
     for _ in 0..count {
         if pos + 1 == slice.len_chars() {
@@ -155,3 +215,24 @@ where
         *pos = pos.saturating_sub(1);
     }
 }
+
+#[cfg(test)]
+mod test {
+    use super::*;
+
+    #[test]
+    fn test_vertical_move() {
+        let text = Rope::from("abcd\nefg\nwrs");
+        let slice = text.slice(..);
+        let pos = pos_at_coords(slice, (0, 4).into());
+
+        let range = Range::new(pos, pos);
+        assert_eq!(
+            coords_at_pos(
+                slice,
+                move_vertically(slice, range, Direction::Forward, 1, false).head
+            ),
+            (1, 2).into()
+        );
+    }
+}
diff --git a/helix-core/src/state.rs b/helix-core/src/state.rs
index 9dcd5548..ab475cab 100644
--- a/helix-core/src/state.rs
+++ b/helix-core/src/state.rs
@@ -1,25 +1,12 @@
-use crate::graphemes::{nth_next_grapheme_boundary, nth_prev_grapheme_boundary, RopeGraphemes};
-use crate::{coords_at_pos, pos_at_coords, ChangeSet, Position, Range, Rope, RopeSlice, Selection};
+use crate::{Rope, Selection};
 
 /// A state represents the current editor state of a single buffer.
 #[derive(Clone)]
 pub struct State {
-    // TODO: fields should be private but we need to refactor commands.rs first
     pub doc: Rope,
     pub selection: Selection,
 }
 
-#[derive(Copy, Clone, PartialEq, Eq)]
-pub enum Direction {
-    Forward,
-    Backward,
-}
-#[derive(Copy, Clone, PartialEq, Eq)]
-pub enum Granularity {
-    Character,
-    Line,
-}
-
 impl State {
     #[must_use]
     pub fn new(doc: Rope) -> Self {
@@ -51,102 +38,4 @@ impl State {
     // syntax
     // foldable
     // changeFilter/transactionFilter
-
-    pub fn move_range(
-        &self,
-        range: Range,
-        dir: Direction,
-        granularity: Granularity,
-        count: usize,
-        extend: bool,
-    ) -> Range {
-        let text = self.doc.slice(..);
-        let pos = range.head;
-        let line = text.char_to_line(pos);
-        // TODO: we can optimize clamping by passing in RopeSlice limited to current line. that way
-        // we stop calculating past start/end of line.
-        let pos = match (dir, granularity) {
-            (Direction::Backward, Granularity::Character) => {
-                let start = text.line_to_char(line);
-                nth_prev_grapheme_boundary(text, pos, count).max(start)
-            }
-            (Direction::Forward, Granularity::Character) => {
-                // Line end is pos at the start of next line - 1
-                // subtract another 1 because the line ends with \n
-                let end = text.line_to_char(line + 1).saturating_sub(2);
-                nth_next_grapheme_boundary(text, pos, count).min(end)
-            }
-            (_, Granularity::Line) => return move_vertically(text, dir, range, count, extend),
-        };
-        Range::new(if extend { range.anchor } else { pos }, pos)
-    }
-
-    pub fn move_selection(
-        &self,
-        dir: Direction,
-        granularity: Granularity,
-        count: usize,
-    ) -> Selection {
-        self.selection
-            .transform(|range| self.move_range(range, dir, granularity, count, false))
-    }
-
-    pub fn extend_selection(
-        &self,
-        dir: Direction,
-        granularity: Granularity,
-        count: usize,
-    ) -> Selection {
-        self.selection
-            .transform(|range| self.move_range(range, dir, granularity, count, true))
-    }
-}
-
-fn move_vertically(
-    text: RopeSlice,
-    dir: Direction,
-    range: Range,
-    count: usize,
-    extend: bool,
-) -> Range {
-    let Position { row, col } = coords_at_pos(text, range.head);
-
-    let horiz = range.horiz.unwrap_or(col as u32);
-
-    let new_line = match dir {
-        Direction::Backward => row.saturating_sub(count),
-        Direction::Forward => std::cmp::min(row.saturating_add(count), text.len_lines() - 1),
-    };
-
-    // convert to 0-indexed, subtract another 1 because len_chars() counts \n
-    let new_line_len = text.line(new_line).len_chars().saturating_sub(2);
-
-    let new_col = std::cmp::min(horiz as usize, new_line_len);
-
-    let pos = pos_at_coords(text, Position::new(new_line, new_col));
-
-    let mut range = Range::new(if extend { range.anchor } else { pos }, pos);
-    range.horiz = Some(horiz);
-    range
-}
-
-#[cfg(test)]
-mod test {
-    use super::*;
-
-    #[test]
-    fn test_vertical_move() {
-        let text = Rope::from("abcd\nefg\nwrs");
-        let slice = text.slice(..);
-        let pos = pos_at_coords(slice, (0, 4).into());
-
-        let range = Range::new(pos, pos);
-        assert_eq!(
-            coords_at_pos(
-                slice,
-                move_vertically(slice, Direction::Forward, range, 1, false).head
-            ),
-            (1, 2).into()
-        );
-    }
 }
diff --git a/helix-term/src/commands.rs b/helix-term/src/commands.rs
index 5b742e43..6165c4c1 100644
--- a/helix-term/src/commands.rs
+++ b/helix-term/src/commands.rs
@@ -1,11 +1,11 @@
 use helix_core::{
     comment, coords_at_pos, graphemes,
     indent::TAB_WIDTH,
-    movement, object, pos_at_coords,
+    movement::{self, Direction},
+    object, pos_at_coords,
     regex::{self, Regex},
-    register, search, selection,
-    state::{Direction, Granularity},
-    Change, ChangeSet, Position, Range, Rope, RopeSlice, Selection, Tendril, Transaction,
+    register, search, selection, Change, ChangeSet, Position, Range, Rope, RopeSlice, Selection,
+    Tendril, Transaction,
 };
 
 use once_cell::sync::Lazy;
@@ -72,36 +72,64 @@ pub type Command = fn(cx: &mut Context);
 pub fn move_char_left(cx: &mut Context) {
     let count = cx.count;
     let doc = cx.doc();
-    let selection = doc
-        .state
-        .move_selection(Direction::Backward, Granularity::Character, count);
+    let text = doc.text().slice(..);
+    let selection = doc.selection().transform(|range| {
+        movement::move_horizontally(
+            text,
+            range,
+            Direction::Backward,
+            count,
+            false, /* extend */
+        )
+    });
     doc.set_selection(selection);
 }
 
 pub fn move_char_right(cx: &mut Context) {
     let count = cx.count;
     let doc = cx.doc();
-    let selection = doc
-        .state
-        .move_selection(Direction::Forward, Granularity::Character, count);
+    let text = doc.text().slice(..);
+    let selection = doc.selection().transform(|range| {
+        movement::move_horizontally(
+            text,
+            range,
+            Direction::Forward,
+            count,
+            false, /* extend */
+        )
+    });
     doc.set_selection(selection);
 }
 
 pub fn move_line_up(cx: &mut Context) {
     let count = cx.count;
     let doc = cx.doc();
-    let selection = doc
-        .state
-        .move_selection(Direction::Backward, Granularity::Line, count);
+    let text = doc.text().slice(..);
+    let selection = doc.selection().transform(|range| {
+        movement::move_vertically(
+            text,
+            range,
+            Direction::Backward,
+            count,
+            false, /* extend */
+        )
+    });
     doc.set_selection(selection);
 }
 
 pub fn move_line_down(cx: &mut Context) {
     let count = cx.count;
     let doc = cx.doc();
-    let selection = doc
-        .state
-        .move_selection(Direction::Forward, Granularity::Line, count);
+    let text = doc.text().slice(..);
+    let selection = doc.selection().transform(|range| {
+        movement::move_vertically(
+            text,
+            range,
+            Direction::Forward,
+            count,
+            false, /* extend */
+        )
+    });
     doc.set_selection(selection);
 }
 
@@ -409,36 +437,64 @@ pub fn half_page_down(cx: &mut Context) {
 pub fn extend_char_left(cx: &mut Context) {
     let count = cx.count;
     let doc = cx.doc();
-    let selection = doc
-        .state
-        .extend_selection(Direction::Backward, Granularity::Character, count);
+    let text = doc.text().slice(..);
+    let selection = doc.selection().transform(|range| {
+        movement::move_horizontally(
+            text,
+            range,
+            Direction::Backward,
+            count,
+            true, /* extend */
+        )
+    });
     doc.set_selection(selection);
 }
 
 pub fn extend_char_right(cx: &mut Context) {
     let count = cx.count;
     let doc = cx.doc();
-    let selection = doc
-        .state
-        .extend_selection(Direction::Forward, Granularity::Character, count);
+    let text = doc.text().slice(..);
+    let selection = doc.selection().transform(|range| {
+        movement::move_horizontally(
+            text,
+            range,
+            Direction::Forward,
+            count,
+            true, /* extend */
+        )
+    });
     doc.set_selection(selection);
 }
 
 pub fn extend_line_up(cx: &mut Context) {
     let count = cx.count;
     let doc = cx.doc();
-    let selection = doc
-        .state
-        .extend_selection(Direction::Backward, Granularity::Line, count);
+    let text = doc.text().slice(..);
+    let selection = doc.selection().transform(|range| {
+        movement::move_vertically(
+            text,
+            range,
+            Direction::Backward,
+            count,
+            true, /* extend */
+        )
+    });
     doc.set_selection(selection);
 }
 
 pub fn extend_line_down(cx: &mut Context) {
     let count = cx.count;
     let doc = cx.doc();
-    let selection = doc
-        .state
-        .extend_selection(Direction::Forward, Granularity::Line, count);
+    let text = doc.text().slice(..);
+    let selection = doc.selection().transform(|range| {
+        movement::move_vertically(
+            text,
+            range,
+            Direction::Forward,
+            count,
+            true, /* extend */
+        )
+    });
     doc.set_selection(selection);
 }
 
diff --git a/helix-term/src/ui/mod.rs b/helix-term/src/ui/mod.rs
index f2376504..f7ba59cd 100644
--- a/helix-term/src/ui/mod.rs
+++ b/helix-term/src/ui/mod.rs
@@ -31,7 +31,7 @@ pub fn regex_prompt(
     prompt: String,
     fun: impl Fn(&mut Document, Regex) + 'static,
 ) -> Prompt {
-    let snapshot = cx.doc().state.clone();
+    let snapshot = cx.doc().selection().clone();
 
     Prompt::new(
         prompt,
@@ -39,9 +39,10 @@ pub fn regex_prompt(
         move |editor: &mut Editor, input: &str, event: PromptEvent| {
             match event {
                 PromptEvent::Abort => {
-                    // revert state
+                    // TODO: also revert doc
+                    // TODO: also revert text
                     let doc = &mut editor.view_mut().doc;
-                    doc.state = snapshot.clone();
+                    doc.set_selection(snapshot.clone());
                 }
                 PromptEvent::Validate => {
                     //
@@ -58,7 +59,8 @@ pub fn regex_prompt(
                             let doc = &mut view.doc;
 
                             // revert state to what it was before the last update
-                            doc.state = snapshot.clone();
+                            // TODO: also revert text
+                            doc.set_selection(snapshot.clone());
 
                             fun(doc, regex);
 
diff --git a/helix-view/src/document.rs b/helix-view/src/document.rs
index 76a3b8e9..e606ec3c 100644
--- a/helix-view/src/document.rs
+++ b/helix-view/src/document.rs
@@ -17,7 +17,8 @@ pub enum Mode {
 }
 
 pub struct Document {
-    pub state: State, // rope + selection
+    // rope + selection
+    state: State,
     path: Option<PathBuf>,
 
     /// Current editing mode.