feat: Add command and bindings to list changes from VCS in opened doc…

…ument(s)

helix-term/src/commands.rs

@@ -1,12 +1,14 @@
 pub(crate) mod dap;
 pub(crate) mod lsp;
 pub(crate) mod typed;
+pub(crate) mod vcs;
 
 pub use dap::*;
 use helix_vcs::Hunk;
 pub use lsp::*;
 use tui::widgets::Row;
 pub use typed::*;
+pub use vcs::*;
 
 use helix_core::{
     char_idx_at_visual_offset, comment,
@@ -77,7 +79,6 @@ pub struct Context<'a> {
     pub register: Option<char>,
     pub count: Option<NonZeroUsize>,
     pub editor: &'a mut Editor,
-
     pub callback: Option<crate::compositor::Callback>,
     pub on_next_key_callback: Option<Box<dyn FnOnce(&mut Context, KeyEvent)>>,
     pub jobs: &'a mut Jobs,
@@ -286,6 +287,7 @@ impl MappableCommand {
         workspace_symbol_picker, "Open workspace symbol picker",
         diagnostics_picker, "Open diagnostic picker",
         workspace_diagnostics_picker, "Open workspace diagnostic picker",
+        vcs_change_picker, "Open VCS changes picker",
         last_picker, "Open last picker",
         insert_at_line_start, "Insert at start of line",
         insert_at_line_end, "Insert at end of line",

helix-term/src/commands/vcs.rs

@@ -0,0 +1,163 @@
+use std::{ops::Range, path::PathBuf};
+
+use helix_core::Selection;
+use helix_lsp::Url;
+use helix_view::theme::Style;
+use helix_view::Document;
+use tui::widgets::{Cell, Row};
+
+use super::{align_view, push_jump, Align, Context, SourcePathFormat};
+use crate::ui::{menu::Item, FilePicker};
+
+/// Picker to list the VCS changes in the current document
+pub fn vcs_change_picker(cx: &mut Context) {
+    let current_doc = doc!(cx.editor);
+
+    let mut changes = Vec::new();
+    add_changes_for_doc(&mut changes, current_doc);
+
+    let picker = vcs_picker(cx, changes, current_doc.url(), SourcePathFormat::Hide);
+    cx.push_layer(Box::new(picker));
+}
+
+// TODO: once both #5472 and #5645 are merged, do a workspace-changes picker
+
+fn add_changes_for_doc(changes: &mut Vec<DiffBlock>, doc: &Document) {
+    let url = match doc.url() {
+        Some(url) => url,
+        None => return,
+    };
+
+    if let Some(diff_handle) = doc.diff_handle() {
+        let file_hunks = diff_handle.hunks();
+        if file_hunks.is_empty() {
+            return;
+        }
+
+        changes.reserve(file_hunks.len() as _);
+
+        for i in 0..file_hunks.len() {
+            let hunk = file_hunks.nth_hunk(i);
+
+            let ty = if hunk.is_pure_insertion() {
+                DiffType::PureInsertion
+            } else if hunk.is_pure_removal() {
+                DiffType::PureRemoval
+            } else {
+                DiffType::Delta
+            };
+
+            let range = hunk.after;
+            let line = doc
+                .text()
+                .get_line(range.start as usize)
+                .map_or_else(Default::default, |l| l.to_string());
+
+            changes.push(DiffBlock {
+                url: url.clone(),
+                ty,
+                line,
+                range,
+            });
+        }
+    }
+}
+
+struct DiffStyles {
+    insertion: Style,
+    removal: Style,
+    delta: Style,
+}
+
+struct DiffBlock {
+    url: Url,
+    ty: DiffType,
+    line: String,
+    range: Range<u32>,
+}
+
+#[derive(Debug, Copy, Clone)]
+enum DiffType {
+    PureInsertion,
+    PureRemoval,
+    Delta,
+}
+
+impl DiffType {
+    fn as_str(&self) -> &'static str {
+        match self {
+            DiffType::PureInsertion => "[+]",
+            DiffType::PureRemoval => "[-]",
+            DiffType::Delta => "[~]",
+        }
+    }
+}
+
+impl Item for DiffBlock {
+    type Data = (DiffStyles, SourcePathFormat);
+
+    fn format(&self, (styles, source_path_format): &Self::Data) -> Row {
+        let path = match source_path_format {
+            SourcePathFormat::Hide => String::new(),
+            SourcePathFormat::Show => {
+                let path = helix_core::path::get_truncated_path(self.url.path());
+                format!("{}:", path.to_string_lossy())
+            }
+        };
+
+        let diff_style = match self.ty {
+            DiffType::PureInsertion => styles.insertion,
+            DiffType::PureRemoval => styles.removal,
+            DiffType::Delta => styles.delta,
+        };
+
+        Row::new([
+            Cell::from(path),
+            Cell::from(self.ty.as_str()).style(diff_style),
+            Cell::from(self.line.as_str()),
+        ])
+    }
+}
+
+fn vcs_picker(
+    cx: &Context,
+    changes: Vec<DiffBlock>,
+    current_path: Option<Url>,
+    show_source_path: SourcePathFormat,
+) -> FilePicker<DiffBlock> {
+    let styles = DiffStyles {
+        insertion: cx.editor.theme.get("diff.plus"),
+        removal: cx.editor.theme.get("diff.minus"),
+        delta: cx.editor.theme.get("diff.delta"),
+    };
+
+    FilePicker::new(
+        changes,
+        (styles, show_source_path),
+        move |cx, DiffBlock { url, range, .. }, action| {
+            if current_path.as_ref() == Some(url) {
+                let (view, doc) = current!(cx.editor);
+                push_jump(view, doc);
+            } else {
+                let path = url.to_file_path().unwrap();
+                cx.editor.open(&path, action).expect("editor.open failed");
+            }
+
+            let (view, doc) = current!(cx.editor);
+
+            let anchor = doc.text().line_to_char(range.start as usize);
+            let head = doc
+                .text()
+                .line_to_char(range.end as usize)
+                .saturating_sub(1);
+            doc.set_selection(view.id, Selection::single(anchor, head));
+            align_view(doc, view, Align::Center);
+        },
+        move |_editor, DiffBlock { url, range, .. }| {
+            Some((
+                PathBuf::from(url.path()).into(),
+                Some((range.start as usize, range.end.saturating_sub(1) as usize)),
+            ))
+        },
+    )
+}

helix-term/src/keymap/default.rs

@@ -219,6 +219,7 @@ pub fn default() -> HashMap<Mode, Keymap> {
             "S" => workspace_symbol_picker,
             "d" => diagnostics_picker,
             "D" => workspace_diagnostics_picker,
+            "v" => vcs_change_picker,
             "a" => code_action,
             "'" => last_picker,
             "g" => { "Debug (experimental)" sticky=true