Merge remote-tracking branch 'origin/master' into debug

5 files changed, 202 insertions, 67 deletions

diff --git a/helix-view/src/document.rs b/helix-view/src/document.rs
index ce5df8ee..76b19a07 100644
--- a/helix-view/src/document.rs
+++ b/helix-view/src/document.rs
@@ -25,6 +25,8 @@ const BUF_SIZE: usize = 8192;
 
 const DEFAULT_INDENT: IndentStyle = IndentStyle::Spaces(4);
 
+pub const SCRATCH_BUFFER_NAME: &str = "[scratch]";
+
 #[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
 pub enum Mode {
     Normal,
@@ -96,7 +98,7 @@ pub struct Document {
     // It can be used as a cell where we will take it out to get some parts of the history and put
     // it back as it separated from the edits. We could split out the parts manually but that will
     // be more troublesome.
-    history: Cell<History>,
+    pub history: Cell<History>,
 
     pub savepoint: Option<Transaction>,
 
@@ -494,7 +496,9 @@ impl Document {
     /// Detect the programming language based on the file type.
     pub fn detect_language(&mut self, theme: Option<&Theme>, config_loader: &syntax::Loader) {
         if let Some(path) = &self.path {
-            let language_config = config_loader.language_config_for_file_name(path);
+            let language_config = config_loader
+                .language_config_for_file_name(path)
+                .or_else(|| config_loader.language_config_for_shebang(self.text()));
             self.set_language(theme, language_config);
         }
     }
@@ -749,19 +753,35 @@ impl Document {
     }
 
     /// Undo modifications to the [`Document`] according to `uk`.
-    pub fn earlier(&mut self, view_id: ViewId, uk: helix_core::history::UndoKind) {
+    pub fn earlier(&mut self, view_id: ViewId, uk: helix_core::history::UndoKind) -> bool {
         let txns = self.history.get_mut().earlier(uk);
+        let mut success = false;
         for txn in txns {
-            self.apply_impl(&txn, view_id);
+            if self.apply_impl(&txn, view_id) {
+                success = true;
+            }
         }
+        if success {
+            // reset changeset to fix len
+            self.changes = ChangeSet::new(self.text());
+        }
+        success
     }
 
     /// Redo modifications to the [`Document`] according to `uk`.
-    pub fn later(&mut self, view_id: ViewId, uk: helix_core::history::UndoKind) {
+    pub fn later(&mut self, view_id: ViewId, uk: helix_core::history::UndoKind) -> bool {
         let txns = self.history.get_mut().later(uk);
+        let mut success = false;
         for txn in txns {
-            self.apply_impl(&txn, view_id);
+            if self.apply_impl(&txn, view_id) {
+                success = true;
+            }
+        }
+        if success {
+            // reset changeset to fix len
+            self.changes = ChangeSet::new(self.text());
         }
+        success
     }
 
     /// Commit pending changes to history
diff --git a/helix-view/src/editor.rs b/helix-view/src/editor.rs
index 40c65c4c..f423de84 100644
--- a/helix-view/src/editor.rs
+++ b/helix-view/src/editor.rs
@@ -1,5 +1,6 @@
 use crate::{
     clipboard::{get_clipboard_provider, ClipboardProvider},
+    document::SCRATCH_BUFFER_NAME,
     graphics::{CursorKind, Rect},
     theme::{self, Theme},
     tree::{self, Tree},
@@ -11,8 +12,8 @@ use futures_util::stream::select_all::SelectAll;
 use tokio_stream::wrappers::UnboundedReceiverStream;
 
 use std::{
-    collections::BTreeMap,
-    collections::HashMap,
+    collections::{BTreeMap, HashMap},
+    io::stdin,
     path::{Path, PathBuf},
     pin::Pin,
     sync::Arc,
@@ -25,8 +26,8 @@ use anyhow::Error;
 pub use helix_core::diagnostic::Severity;
 pub use helix_core::register::Registers;
 use helix_core::syntax;
-use helix_core::Position;
 use helix_dap as dap;
+use helix_core::{Position, Selection};
 
 use serde::Deserialize;
 
@@ -39,7 +40,7 @@ where
 }
 
 #[derive(Debug, Clone, PartialEq, Deserialize)]
-#[serde(rename_all = "kebab-case", default)]
+#[serde(rename_all = "kebab-case", default, deny_unknown_fields)]
 pub struct Config {
     /// Padding to keep between the edge of the screen and the cursor when scrolling. Defaults to 5.
     pub scrolloff: usize,
@@ -138,6 +139,8 @@ pub struct Editor {
 
     pub idle_timer: Pin<Box<Sleep>>,
     pub last_motion: Option<Motion>,
+
+    pub exit_code: i32,
 }
 
 #[derive(Debug, Copy, Clone)]
@@ -179,6 +182,7 @@ impl Editor {
             idle_timer: Box::pin(sleep(config.idle_timeout)),
             last_motion: None,
             config,
+            exit_code: 0,
         }
     }
 
@@ -208,6 +212,12 @@ impl Editor {
     }
 
     pub fn set_theme(&mut self, theme: Theme) {
+        // `ui.selection` is the only scope required to be able to render a theme.
+        if theme.find_scope_index("ui.selection").is_none() {
+            self.set_error("Invalid theme: `ui.selection` required".to_owned());
+            return;
+        }
+
         let scopes = theme.scopes();
         for config in self
             .syn_loader
@@ -238,9 +248,28 @@ impl Editor {
         }
     }
 
+    fn replace_document_in_view(&mut self, current_view: ViewId, doc_id: DocumentId) {
+        let view = self.tree.get_mut(current_view);
+        view.doc = doc_id;
+        view.offset = Position::default();
+
+        let doc = self.documents.get_mut(&doc_id).unwrap();
+
+        // initialize selection for view
+        doc.selections
+            .entry(view.id)
+            .or_insert_with(|| Selection::point(0));
+        // TODO: reuse align_view
+        let pos = doc
+            .selection(view.id)
+            .primary()
+            .cursor(doc.text().slice(..));
+        let line = doc.text().char_to_line(pos);
+        view.offset.row = line.saturating_sub(view.inner_area().height as usize / 2);
+    }
+
     pub fn switch(&mut self, id: DocumentId, action: Action) {
         use crate::tree::Layout;
-        use helix_core::Selection;
 
         if !self.documents.contains_key(&id) {
             log::error!("cannot switch to document that does not exist (anymore)");
@@ -274,26 +303,19 @@ impl Editor {
                     view.jumps.push(jump);
                     view.last_accessed_doc = Some(view.doc);
                 }
-                view.doc = id;
-                view.offset = Position::default();
 
-                let (view, doc) = current!(self);
-
-                // initialize selection for view
-                doc.selections
-                    .entry(view.id)
-                    .or_insert_with(|| Selection::point(0));
-                // TODO: reuse align_view
-                let pos = doc
-                    .selection(view.id)
-                    .primary()
-                    .cursor(doc.text().slice(..));
-                let line = doc.text().char_to_line(pos);
-                view.offset.row = line.saturating_sub(view.inner_area().height as usize / 2);
+                let view_id = view.id;
+                self.replace_document_in_view(view_id, id);
 
                 return;
             }
             Action::Load => {
+                let view_id = view!(self).id;
+                if let Some(doc) = self.document_mut(id) {
+                    if doc.selections().is_empty() {
+                        doc.selections.insert(view_id, Selection::point(0));
+                    }
+                }
                 return;
             }
             Action::HorizontalSplit => {
@@ -315,16 +337,29 @@ impl Editor {
         self._refresh();
     }
 
-    pub fn new_file(&mut self, action: Action) -> DocumentId {
+    fn new_document(&mut self, mut document: Document) -> DocumentId {
         let id = DocumentId(self.next_document_id);
         self.next_document_id += 1;
-        let mut doc = Document::default();
-        doc.id = id;
-        self.documents.insert(id, doc);
+        document.id = id;
+        self.documents.insert(id, document);
+        id
+    }
+
+    fn new_file_from_document(&mut self, action: Action, document: Document) -> DocumentId {
+        let id = self.new_document(document);
         self.switch(id, action);
         id
     }
 
+    pub fn new_file(&mut self, action: Action) -> DocumentId {
+        self.new_file_from_document(action, Document::default())
+    }
+
+    pub fn new_file_from_stdin(&mut self, action: Action) -> Result<DocumentId, Error> {
+        let (rope, encoding) = crate::document::from_reader(&mut stdin(), None)?;
+        Ok(self.new_file_from_document(action, Document::from(rope, Some(encoding))))
+    }
+
     pub fn open(&mut self, path: PathBuf, action: Action) -> Result<DocumentId, Error> {
         let path = helix_core::path::get_canonicalized_path(&path)?;
 
@@ -381,7 +416,7 @@ impl Editor {
         Ok(id)
     }
 
-    pub fn close(&mut self, id: ViewId, close_buffer: bool) {
+    pub fn close(&mut self, id: ViewId) {
         let view = self.tree.get(self.tree.focus);
         // remove selection
         self.documents
@@ -390,18 +425,66 @@ impl Editor {
             .selections
             .remove(&id);
 
-        if close_buffer {
-            // get around borrowck issues
-            let doc = &self.documents[&view.doc];
+        self.tree.remove(id);
+        self._refresh();
+    }
 
-            if let Some(language_server) = doc.language_server() {
-                tokio::spawn(language_server.text_document_did_close(doc.identifier()));
-            }
-            self.documents.remove(&view.doc);
+    pub fn close_document(&mut self, doc_id: DocumentId, force: bool) -> anyhow::Result<()> {
+        let doc = match self.documents.get(&doc_id) {
+            Some(doc) => doc,
+            None => anyhow::bail!("document does not exist"),
+        };
+
+        if !force && doc.is_modified() {
+            anyhow::bail!(
+                "buffer {:?} is modified",
+                doc.relative_path()
+                    .map(|path| path.to_string_lossy().to_string())
+                    .unwrap_or_else(|| SCRATCH_BUFFER_NAME.into())
+            );
+        }
+
+        if let Some(language_server) = doc.language_server() {
+            tokio::spawn(language_server.text_document_did_close(doc.identifier()));
+        }
+
+        let views_to_close = self
+            .tree
+            .views()
+            .filter_map(|(view, _focus)| {
+                if view.doc == doc_id {
+                    Some(view.id)
+                } else {
+                    None
+                }
+            })
+            .collect::<Vec<_>>();
+
+        for view_id in views_to_close {
+            self.close(view_id);
+        }
+
+        self.documents.remove(&doc_id);
+
+        // If the document we removed was visible in all views, we will have no more views. We don't
+        // want to close the editor just for a simple buffer close, so we need to create a new view
+        // containing either an existing document, or a brand new document.
+        if self.tree.views().peekable().peek().is_none() {
+            let doc_id = self
+                .documents
+                .iter()
+                .map(|(&doc_id, _)| doc_id)
+                .next()
+                .unwrap_or_else(|| self.new_document(Document::default()));
+            let view = View::new(doc_id);
+            let view_id = self.tree.insert(view);
+            let doc = self.documents.get_mut(&doc_id).unwrap();
+            doc.selections.insert(view_id, Selection::point(0));
         }
 
-        self.tree.remove(id);
         self._refresh();
+
+        Ok(())
     }
 
     pub fn resize(&mut self, area: Rect) {
diff --git a/helix-view/src/macros.rs b/helix-view/src/macros.rs
index 63d76a42..04f8df94 100644
--- a/helix-view/src/macros.rs
+++ b/helix-view/src/macros.rs
@@ -11,10 +11,19 @@
 /// Returns `(&mut View, &mut Document)`
 #[macro_export]
 macro_rules! current {
-    ( $( $editor:ident ).+ ) => {{
-        let view = $crate::view_mut!( $( $editor ).+ );
+    ($editor:expr) => {{
+        let view = $crate::view_mut!($editor);
         let id = view.doc;
-        let doc = $( $editor ).+ .documents.get_mut(&id).unwrap();
+        let doc = $editor.documents.get_mut(&id).unwrap();
+        (view, doc)
+    }};
+}
+
+#[macro_export]
+macro_rules! current_ref {
+    ($editor:expr) => {{
+        let view = $editor.tree.get($editor.tree.focus);
+        let doc = &$editor.documents[&view.doc];
         (view, doc)
     }};
 }
@@ -23,8 +32,8 @@ macro_rules! current {
 /// Returns `&mut Document`
 #[macro_export]
 macro_rules! doc_mut {
-    ( $( $editor:ident ).+ ) => {{
-        $crate::current!( $( $editor ).+ ).1
+    ($editor:expr) => {{
+        $crate::current!($editor).1
     }};
 }
 
@@ -32,8 +41,8 @@ macro_rules! doc_mut {
 /// Returns `&mut View`
 #[macro_export]
 macro_rules! view_mut {
-    ( $( $editor:ident ).+ ) => {{
-        $( $editor ).+ .tree.get_mut($( $editor ).+ .tree.focus)
+    ($editor:expr) => {{
+        $editor.tree.get_mut($editor.tree.focus)
     }};
 }
 
@@ -41,23 +50,14 @@ macro_rules! view_mut {
 /// Returns `&View`
 #[macro_export]
 macro_rules! view {
-    ( $( $editor:ident ).+ ) => {{
-        $( $editor ).+ .tree.get($( $editor ).+ .tree.focus)
+    ($editor:expr) => {{
+        $editor.tree.get($editor.tree.focus)
     }};
 }
 
 #[macro_export]
 macro_rules! doc {
-    ( $( $editor:ident ).+ ) => {{
-        $crate::current_ref!( $( $editor ).+ ).1
-    }};
-}
-
-#[macro_export]
-macro_rules! current_ref {
-    ( $( $editor:ident ).+ ) => {{
-        let view = $( $editor ).+ .tree.get($( $editor ).+ .tree.focus);
-        let doc = &$( $editor ).+ .documents[&view.doc];
-        (view, doc)
+    ($editor:expr) => {{
+        $crate::current_ref!($editor).1
     }};
 }
diff --git a/helix-view/src/tree.rs b/helix-view/src/tree.rs
index 064334b1..de5046ac 100644
--- a/helix-view/src/tree.rs
+++ b/helix-view/src/tree.rs
@@ -314,6 +314,9 @@ impl Tree {
 
     pub fn recalculate(&mut self) {
         if self.is_empty() {
+            // There are no more views, so the tree should focus itself again.
+            self.focus = self.root;
+
             return;
         }
 
diff --git a/helix-view/src/view.rs b/helix-view/src/view.rs
index ee236e94..02aa1327 100644
--- a/helix-view/src/view.rs
+++ b/helix-view/src/view.rs
@@ -54,6 +54,10 @@ impl JumpList {
             None
         }
     }
+
+    pub fn remove(&mut self, doc_id: &DocumentId) {
+        self.jumps.retain(|(other_id, _)| other_id != doc_id);
+    }
 }
 
 #[derive(Debug)]
@@ -85,7 +89,12 @@ impl View {
         self.area.clip_left(OFFSET).clip_bottom(1) // -1 for statusline
     }
 
-    pub fn ensure_cursor_in_view(&mut self, doc: &Document, scrolloff: usize) {
+    //
+    pub fn offset_coords_to_in_view(
+        &self,
+        doc: &Document,
+        scrolloff: usize,
+    ) -> Option<(usize, usize)> {
         let cursor = doc
             .selection(self.id)
             .primary()
@@ -104,23 +113,43 @@ impl View {
 
         let last_col = self.offset.col + inner_area.width.saturating_sub(1) as usize;
 
-        if line > last_line.saturating_sub(scrolloff) {
+        let row = if line > last_line.saturating_sub(scrolloff) {
             // scroll down
-            self.offset.row += line - (last_line.saturating_sub(scrolloff));
+            self.offset.row + line - (last_line.saturating_sub(scrolloff))
         } else if line < self.offset.row + scrolloff {
             // scroll up
-            self.offset.row = line.saturating_sub(scrolloff);
-        }
+            line.saturating_sub(scrolloff)
+        } else {
+            self.offset.row
+        };
 
-        if col > last_col.saturating_sub(scrolloff) {
+        let col = if col > last_col.saturating_sub(scrolloff) {
             // scroll right
-            self.offset.col += col - (last_col.saturating_sub(scrolloff));
+            self.offset.col + col - (last_col.saturating_sub(scrolloff))
         } else if col < self.offset.col + scrolloff {
             // scroll left
-            self.offset.col = col.saturating_sub(scrolloff);
+            col.saturating_sub(scrolloff)
+        } else {
+            self.offset.col
+        };
+        if row == self.offset.row && col == self.offset.col {
+            None
+        } else {
+            Some((row, col))
+        }
+    }
+
+    pub fn ensure_cursor_in_view(&mut self, doc: &Document, scrolloff: usize) {
+        if let Some((row, col)) = self.offset_coords_to_in_view(doc, scrolloff) {
+            self.offset.row = row;
+            self.offset.col = col;
         }
     }
 
+    pub fn is_cursor_in_view(&mut self, doc: &Document, scrolloff: usize) -> bool {
+        self.offset_coords_to_in_view(doc, scrolloff).is_none()
+    }
+
     /// Calculates the last visible line on screen
     #[inline]
     pub fn last_line(&self, doc: &Document) -> usize {