Add wrap-around navigation setting (#26)

* Add wrap-around navigation setting (default off)

Chunk/conflict navigation no longer wraps around by default.
A new "Wrap around navigation" toggle in Preferences lets users
opt-in to the previous wrap behavior.

Closes #10

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* Fix UI test: don't hardcode chunk count

The fixture files produce 3 chunks, not 2. Parse the label
dynamically instead.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* Fix Makefile: build release binary before UI tests

The test-release target was running pytest against
target/release/mergers without rebuilding it first, so UI tests
could run against a stale binary.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* Fix merge view cursor starting at end of buffer

GTK's set_text leaves the cursor at the end, so conflict/chunk
navigation couldn't find anything forward on first use. Place
cursors at start after setting text, matching diff_view behavior.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* Add nav button sensitivity at chunk boundaries

When wrap-around navigation is off, prev/next chunk buttons now become
insensitive when there is no chunk to navigate to in that direction.
Buttons also start insensitive until the initial async diff completes.

Applies to diff view (chunk nav), merge view (chunk nav + conflict nav).

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* Update chunk/conflict label on cursor movement

When the user clicks or moves the cursor into a change region, the
chunk label now shows "Change X of Y" and nav button sensitivity
updates accordingly. In merge view, the conflict label also tracks
cursor position on conflict marker lines.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* Track conflict label by cursor position within block

The conflict label now shows "Conflict X of Y" when the cursor is
anywhere inside a conflict block (between <<<<<<< and >>>>>>>), not
just on the exact marker line.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* bump to 0.5.1

---------

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

Author: joske

Cargo.lock

@@ -1,6 +1,6 @@
 [package]
 name = "mergers"
-version = "0.5.0"
+version = "0.5.1"
 edition = "2024"
 description = "A visual diff and merge tool for files and directories"
 license = "GPL-2.0"

Cargo.toml

@@ -15,6 +15,7 @@ $(VENV): tests/ui_integration/requirements.txt
 	@touch $(VENV)
 
 test-release: $(VENV)
+	cargo build --release
 	xvfb-run -a cargo test
 	xvfb-run -a $(PYTEST) tests/ui_integration/ -v
 

Makefile

@@ -3,6 +3,7 @@ use std::path::PathBuf;
 
 #[derive(Debug, Clone, Serialize, Deserialize)]
 #[serde(default)]
+#[allow(clippy::struct_excessive_bools)]
 pub struct Settings {
     pub font: String,
     pub style_scheme: String,
@@ -11,6 +12,7 @@ pub struct Settings {
     pub tab_width: u32,
     pub highlight_current_line: bool,
     pub hide_hidden_files: bool,
+    pub wrap_around_navigation: bool,
     pub dir_filters: Vec<String>,
 }
 
@@ -24,6 +26,7 @@ impl Default for Settings {
             tab_width: 4,
             highlight_current_line: true,
             hide_hidden_files: true,
+            wrap_around_navigation: false,
             dir_filters: vec![
                 ".git".into(),
                 ".svn".into(),
@@ -96,6 +99,7 @@ mod tests {
         assert!(s.show_line_numbers);
         assert_eq!(s.tab_width, 4);
         assert!(s.dir_filters.contains(&".git".to_string()));
+        assert!(!s.wrap_around_navigation);
     }
 
     #[test]
@@ -108,6 +112,10 @@ mod tests {
         assert_eq!(original.tab_width, parsed.tab_width);
         assert_eq!(original.show_line_numbers, parsed.show_line_numbers);
         assert_eq!(original.wrap_mode, parsed.wrap_mode);
+        assert_eq!(
+            original.wrap_around_navigation,
+            parsed.wrap_around_navigation
+        );
         assert_eq!(original.dir_filters, parsed.dir_filters);
     }
 

src/settings.rs

@@ -1527,6 +1527,7 @@ pub(super) fn navigate_chunk(
     right_buf: &TextBuffer,
     right_scroll: &ScrolledWindow,
     active_tv: &TextView,
+    wrap: bool,
 ) {
     let cursor_line = cursor_line_from_view(active_tv);
     let side = if active_tv == right_tv {
@@ -1535,7 +1536,7 @@ pub(super) fn navigate_chunk(
         Side::A
     };
 
-    if let Some(idx) = diff_state::find_next_chunk(chunks, cursor_line, direction, side) {
+    if let Some(idx) = diff_state::find_next_chunk(chunks, cursor_line, direction, side, wrap) {
         current_chunk.set(Some(idx));
         let chunk = &chunks[idx];
         scroll_to_line(left_tv, left_buf, chunk.start_a, left_scroll);
@@ -1586,6 +1587,26 @@ pub(super) fn update_chunk_label(label: &Label, chunks: &[DiffChunk], current: O
     label.set_label(&diff_state::format_chunk_label(chunks, current));
 }
 
+/// Update sensitivity of prev/next chunk nav buttons based on cursor position.
+pub(super) fn update_chunk_nav_sensitivity(
+    prev_btn: &Button,
+    next_btn: &Button,
+    chunks: &[DiffChunk],
+    active_tv: &TextView,
+    right_tv: &TextView,
+    wrap: bool,
+) {
+    let cursor_line = cursor_line_from_view(active_tv);
+    let side = if active_tv == right_tv {
+        Side::B
+    } else {
+        Side::A
+    };
+    let (prev, next) = diff_state::chunk_nav_sensitivity(chunks, cursor_line, side, wrap);
+    prev_btn.set_sensitive(prev);
+    next_btn.set_sensitive(next);
+}
+
 // ─── Scroll synchronization ───────────────────────────────────────────────
 
 pub(super) fn setup_scroll_sync(