From 9a76f90f070e0b3d11f61bf42e4e30a7da26b43f Mon Sep 17 00:00:00 2001
From: Oliver Hagmann <268387159+ohagmann@users.noreply.github.com>
Date: Tue, 20 Oct 2026 18:38:28 +0200
Subject: [PATCH] M5: the arrow keys move the selected comment
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With a comment selected, the arrow keys scrolled the view (↑ ↓) or turned the page (← →), so
a text box, rectangle or line could only be placed with the mouse. Now an arrow key moves the
selected comment a screen pixel, and ⌘/Ctrl or Shift and an arrow ten, as Edit text nudges
objects; up is up on screen whatever the zoom, the page's rotation and the view's. Each press
is one undo step (Edit::MoveAnnotation). The keys are taken before the view's navigation,
which has them back once nothing is selected. Text markup stays with its text, and a locked
comment where it is.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
---
 ROADMAP.md                          |  2 ++
 crates/ui-egui/src/comments.rs      | 49 +++++++++++++++++++++++++++++
 crates/ui-egui/src/lib.rs           |  2 ++
 crates/ui-egui/tests/it/comments.rs | 44 ++++++++++++++++++++++++++
 docs/ui-parity.md                   |  2 +-
 parity/acrobat-features.toml        | 12 +++++++
 6 files changed, 110 insertions(+), 1 deletion(-)

diff --git a/ROADMAP.md b/ROADMAP.md
index bc057209c..9164899c0 100644
--- a/ROADMAP.md
+++ b/ROADMAP.md
@@ -225,6 +225,8 @@ Ranked; detail and the full milestone table in [docs/roadmap.md](docs/roadmap.md
 - **2026-10-20 (M3, #3541/#3620):** Comment hover follows the individual marked lines instead of the enclosing multiline rectangle, and overlapping comments follow paint order. Synthetic UI regressions cover all four text-markup kinds, page/view rotations, neighboring highlights, legacy rectangle fallback and unchanged PDF bytes. Estimates unchanged.
 - **2026-10-20 (M10, #3532 partial):** Vector printing retains existing widget artwork when its appearance lacks Subtype. A print-owned copy adds Form dispatch metadata. The source stream and all explicit subtypes stay unchanged. Synthetic source/output raster checks cover resources, selected/shared appearances, placement, flags and content modes. Appearance regeneration and physical printer validation remain outside this fix. Estimates unchanged.
 
+- **2026-10-20 (M5, arrow keys move comments):** With a comment selected, the arrow keys move it a screen pixel and ⌘/Ctrl or Shift and an arrow ten, instead of scrolling the view or turning the page; up is up on screen at any zoom and rotation, and each press is one undo step. Text markup and locked comments stay put. Estimates unchanged.
+
 - **2026-10-19 (M14, #3373):** The main menu and its long submenus scroll in short windows, keeping their commands reachable. Estimates unchanged.
 
 - **2026-10-19 (M3, #3387):** Save-prompt shortcuts yield to later consent and utility dialogs; a synthetic UI regression checks that an edited document stays open. Estimates unchanged.
diff --git a/crates/ui-egui/src/comments.rs b/crates/ui-egui/src/comments.rs
index d80f988b7..541e1c8ad 100644
--- a/crates/ui-egui/src/comments.rs
+++ b/crates/ui-egui/src/comments.rs
@@ -1823,6 +1823,55 @@ pub(crate) fn keys(ctx: &egui::Context, view: &mut DocView, tool: &mut QuickTool
     }
 }
 
+/// The arrow keys move the selected comment a screen pixel; with ⌘/Ctrl or Shift, ten. Up is up
+/// on screen whatever the zoom, the page's rotation and the view's; the keys are taken before
+/// the view scrolls or turns the page with them. Each press is one undo step. Text markup stays
+/// with its text, and a locked comment where it is.
+pub(crate) fn nudge_keys(ctx: &egui::Context, view: &mut DocView, info: &DocInfo) {
+    if ctx.egui_wants_keyboard_input() || view.pending_edit.is_some() {
+        return;
+    }
+    let cv = &view.comments;
+    if cv.gesture.is_some() || cv.composer.is_some() {
+        return;
+    }
+    let Some((page, index)) = cv.selected else { return };
+    let movable =
+        info.annotations.iter().any(|a| a.page == page && a.index == index && a.in_reply_to.is_none() && !is_markup(&a.subtype) && !a.locked);
+    let (Some(xf), Some(p)) = (view.page_xform(page), info.pages.get(page)) else { return };
+    if !movable {
+        return;
+    }
+    use egui::{Key, Modifiers};
+    let mut step = egui::Vec2::ZERO;
+    ctx.input_mut(|i| {
+        for (key, direction) in
+            [(Key::ArrowLeft, vec2(-1.0, 0.0)), (Key::ArrowRight, vec2(1.0, 0.0)), (Key::ArrowUp, vec2(0.0, -1.0)), (Key::ArrowDown, vec2(0.0, 1.0))]
+        {
+            // The modified patterns first: a plain one also matches a Shift press.
+            if i.consume_key(Modifiers::COMMAND, key) || i.consume_key(Modifiers::SHIFT, key) {
+                step += direction * 10.0;
+            } else if i.consume_key(Modifiers::NONE, key) {
+                step += direction;
+            }
+        }
+    });
+    if step == egui::Vec2::ZERO {
+        return;
+    }
+    // The step on screen, in user space: from the page's centre to `step` pixels away.
+    let user = |s: Pos2| {
+        let (vx, vy) = xf.screen_to_view(s);
+        let u = p.view_to_user(vx, vy);
+        [f64::from(u[0]), f64::from(u[1])]
+    };
+    let (a, b) = (user(xf.rect.center()), user(xf.rect.center() + step));
+    let (dx, dy) = (b[0] - a[0], b[1] - a[1]);
+    if dx.is_finite() && dy.is_finite() && (dx != 0.0 || dy != 0.0) {
+        view.pending_edit = Some(Edit::MoveAnnotation { page, index, dx, dy });
+    }
+}
+
 /// Save attachment… and, for a PDF, Open in a new tab, first in a file attachment comment's
 /// menus as in the Attachments panel: the comment is where the reader finds its file. Reading
 /// the file changes nothing, so a read-only document offers them too.
diff --git a/crates/ui-egui/src/lib.rs b/crates/ui-egui/src/lib.rs
index 64b22ff18..d618e4ba2 100644
--- a/crates/ui-egui/src/lib.rs
+++ b/crates/ui-egui/src/lib.rs
@@ -3023,6 +3023,8 @@ impl PdfCraftApp {
                 && let Some(doc) = self.session.get(self.views[i].id).filter(|d| d.allows_modification())
             {
                 object_ui::nudge_keys(ctx, &mut self.views[i], doc);
+            } else if let Some(doc) = self.session.get(self.views[i].id).filter(|d| d.allows_annotation()) {
+                comments::nudge_keys(ctx, &mut self.views[i], &doc.info);
             }
             // A selected field moves with the arrows too (Prepare a form, #2608), before the view
             // turns the page with them.
diff --git a/crates/ui-egui/tests/it/comments.rs b/crates/ui-egui/tests/it/comments.rs
index 6194c7516..5e6227843 100644
--- a/crates/ui-egui/tests/it/comments.rs
+++ b/crates/ui-egui/tests/it/comments.rs
@@ -860,6 +860,50 @@ fn line_ends_are_dragged_to_change_length_and_angle() {
     assert!((p[1][0] - 200.0).abs() < 1.0 && (p[1][1] - 160.0).abs() < 1.0, "{p:?}");
 }
 
+/// The arrow keys move the selected comment a screen pixel, ⌘/Ctrl or Shift and an arrow ten,
+/// instead of scrolling or turning the page; each press is one undo step. Without a selection
+/// the arrows scroll and turn pages as before.
+#[test]
+fn arrow_keys_nudge_the_selected_comment() {
+    use egui::{Key, Modifiers};
+    let mut h = harness(|app| app.set_option("quick", "square").unwrap());
+    drag_pt(&mut h, (40.0, 100.0), (140.0, 40.0));
+    h.state_mut().set_option("quick", "select").unwrap();
+    click_pt(&mut h, (90.0, 70.0));
+    assert_eq!(h.state().views[0].comments.selected, Some((0, 0)));
+    // One screen pixel in user space, at this zoom.
+    let pixel = 300.0 / h.state().views[0].page_screen_rect(0).unwrap().width();
+    let before = comments(&h)[0].rect;
+    h.key_press(Key::ArrowRight);
+    h.run_steps(3);
+    let r = comments(&h)[0].rect;
+    assert!((r[0] - before[0] - pixel).abs() < 0.01 && (r[1] - before[1]).abs() < 0.01, "one pixel right: {r:?} from {before:?}");
+    assert_eq!(h.state().views[0].current, 0, "the page didn't turn");
+    let id = h.state().views[0].id;
+    assert_eq!(h.state().session.get(id).unwrap().can_undo(), Some("Move comment"));
+    // ⌘/Ctrl and Shift: ten pixels (down on screen is down in user space here).
+    h.key_press_modifiers(Modifiers::COMMAND, Key::ArrowDown);
+    h.run_steps(3);
+    let r2 = comments(&h)[0].rect;
+    assert!((r[1] - r2[1] - 10.0 * pixel).abs() < 0.01 && (r2[0] - r[0]).abs() < 0.01, "ten pixels down: {r2:?} from {r:?}");
+    h.key_press_modifiers(Modifiers::SHIFT, Key::ArrowLeft);
+    h.run_steps(3);
+    let r3 = comments(&h)[0].rect;
+    assert!((r2[0] - r3[0] - 10.0 * pixel).abs() < 0.01, "ten pixels left: {r3:?} from {r2:?}");
+    h.state_mut().undo();
+    h.run_steps(2);
+    assert!((comments(&h)[0].rect[0] - r2[0]).abs() < 0.01, "each press is one undo step");
+    // Nothing selected: → turns the page again.
+    h.key_press(Key::Escape);
+    h.run_steps(2);
+    assert_eq!(h.state().views[0].comments.selected, None);
+    let rect = comments(&h)[0].rect;
+    h.key_press(Key::ArrowRight);
+    h.run_steps(3);
+    assert_eq!(comments(&h)[0].rect, rect, "the comment stays");
+    assert_eq!(h.state().views[0].current, 1, "and the view goes to the next page");
+}
+
 #[test]
 fn a_shape_just_drawn_resizes_from_its_handles_without_the_select_tool() {
     // #2338: the new shape showed its handles, but only the Select tool answered them.
diff --git a/docs/ui-parity.md b/docs/ui-parity.md
index c12461793..703f1e9d8 100644
--- a/docs/ui-parity.md
+++ b/docs/ui-parity.md
@@ -52,7 +52,7 @@ No dump of Acrobat's menu tree has been diffed against the registry yet (gap 24)
 | Rulers, grids, snap to grid, guides | yes | no | planned |
 | Cursor coordinates, line weights | yes | no | planned |
 | Measuring snap to paths, endpoints, midpoints, intersections | yes | yes | shipped |
-| Nudge selected objects with arrow keys (Shift for larger steps) | yes | yes in Edit text: a point, Shift ten points, for selected objects, images and an open paragraph's box (#1520); and in Prepare a form, for the selected field (#2608) | shipped |
+| Nudge selected objects with arrow keys (Shift for larger steps) | yes | yes in Edit text: a point, Shift ten points, for selected objects, images and an open paragraph's box (#1520); and in Prepare a form, for the selected field (#2608); a selected comment: a screen pixel, ⌘/Ctrl or Shift ten | shipped |
 | Single-key tool accelerators (H, V, Z, …) | yes, opt-in | no | planned |
 | Context menus on pages, thumbnails, comments, fields | yes | thumbnails, comments, fields | partial |
 | Comment pop-ups as movable windows, connector lines | yes | inline in the panel | planned |
diff --git a/parity/acrobat-features.toml b/parity/acrobat-features.toml
index 362c2aa77..d55fe67f6 100644
--- a/parity/acrobat-features.toml
+++ b/parity/acrobat-features.toml
@@ -3971,6 +3971,18 @@ tools = ["comment_delete"]
 evidence = ["crates/ui-egui/tests/it/comments.rs::comments_are_selected_moved_and_deleted_with_the_select_tool", "crates/annot/src/tests.rs::delete_takes_popup_and_reply_chain"]
 notes = "deletes the pop-up and the reply thread"
 
+[[feature]]
+id = "comment.keyboard-nudge"
+title = "Move the selected comment with the arrow keys"
+area = "E"
+tier = "P2"
+milestone = "M5"
+status = "shipped"
+commands = []
+tools = ["comment_edit"]
+evidence = ["crates/ui-egui/tests/it/comments.rs::arrow_keys_nudge_the_selected_comment"]
+notes = "With a comment selected (Select tool, or a Fill & Sign mark picked up), an arrow key moves it a screen pixel and ⌘/Ctrl or Shift and an arrow ten, up being up on screen whatever the zoom and rotation; each press is one undo step, and the arrows scroll and turn pages again once nothing is selected. Text markup stays with its text and a locked comment where it is. Headless, comment_edit's `move` takes the offset in points."
+
 [[feature]]
 id = "comment.reshape"
 title = "Change a line's ends and a polygon's corners after drawing"