Merge PR #4111: fix(edit): Delete removes the selected paragraph or objects in Edit text

crates/ui-egui/src/object_ui.rs: main removed the tests module's translation test; kept the PR's two
new delete tests and dropped the translation test.

crates/ui-egui/src/lib.rs

@@ -3027,6 +3027,7 @@ 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);
+                object_ui::delete_keys(ctx, &mut self.views[i]);
             }
             // A selected field moves with the arrows too (Prepare a form, #2608), before the view
             // turns the page with them.

crates/ui-egui/src/object_ui.rs

@@ -384,6 +384,46 @@ pub(crate) fn nudge_keys(ctx: &egui::Context, view: &mut DocView, doc: &Document
     }
 }
 
+/// Delete (or Backspace) removes the selected objects, as in Acrobat: a paragraph selected by its
+/// frame, or everything an area selection took, goes at once instead of one typed character at a
+/// time.
+pub(crate) fn delete_keys(ctx: &egui::Context, view: &mut DocView) {
+    if ctx.egui_wants_keyboard_input() || view.pending_edit.is_some() || view.objects.gesture.is_some() {
+        return;
+    }
+    let Some(page) = view.objects.page.filter(|_| !view.objects.selected.is_empty()) else { return };
+    use egui::{Key, Modifiers};
+    if !ctx.input_mut(|i| i.consume_key(Modifiers::NONE, Key::Delete) || i.consume_key(Modifiers::NONE, Key::Backspace)) {
+        return;
+    }
+    // The selection stays until the edit applies: `prepare` clears it when the document changes,
+    // and a refused delete (text used as a clipping path) leaves it selected.
+    view.pending_edit = delete_edit(page, view.objects.selected.iter().map(|o| o.target).collect());
+}
+
+/// The edit that deletes `targets` (indexes into one inventory of `page`) as one undo step.
+/// Each deletion renumbers only what follows it in its own inventory, so paragraphs and images
+/// go from the last to the first, and added content, which the source inventories leave out,
+/// after them.
+fn delete_edit(page: usize, mut targets: Vec<ObjectTarget>) -> Option<Edit> {
+    targets.sort_by_key(|t| (t.kind == ObjectKind::Added, std::cmp::Reverse(t.index)));
+    targets.dedup();
+    let mut edits: Vec<Edit> = targets
+        .into_iter()
+        .map(|t| match t.kind {
+            ObjectKind::Text => Edit::EditTextBlock { page, block: t.index, text: String::new(), style: pdfcraft_engine::BlockStyle::default() },
+            ObjectKind::Image => Edit::EditPageImage { page, index: t.index, change: pdfcraft_engine::ImageEdit::Delete },
+            ObjectKind::Added => Edit::DeleteContent { page, index: t.index },
+        })
+        .collect();
+    if edits.len() > 1 {
+        // "Delete content" is an edit label already, so the history reads the same in every language.
+        Some(Edit::Batch { label: "Delete content".into(), edits })
+    } else {
+        edits.pop()
+    }
+}
+
 pub(crate) fn paint(painter: &egui::Painter, xf: &PageXform, page: usize, info: &DocInfo, selection: &ObjectSelection) {
     if selection.page != Some(page) {
         return;
@@ -415,3 +455,40 @@ pub(crate) fn move_error(error: &pdfcraft_engine::EditError) -> String {
         _ => tl!("These objects could not be moved. Select them again and try a smaller move.").into(),
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    fn t(kind: ObjectKind, index: usize) -> ObjectTarget {
+        ObjectTarget { kind, index }
+    }
+
+    /// Deleting renumbers what follows in the same inventory, so the batch takes each inventory
+    /// from its last item to its first, and added content (outside the source inventories) last.
+    #[test]
+    fn several_objects_delete_last_first_in_one_step() {
+        let targets = vec![t(ObjectKind::Added, 0), t(ObjectKind::Text, 1), t(ObjectKind::Image, 0), t(ObjectKind::Text, 3), t(ObjectKind::Added, 2)];
+        let Some(Edit::Batch { label, edits }) = delete_edit(0, targets) else { panic!("several objects make one batch") };
+        assert_eq!(label, "Delete content");
+        let order: Vec<(char, usize)> = edits
+            .iter()
+            .map(|e| match e {
+                Edit::EditTextBlock { block, text, .. } => {
+                    assert!(text.is_empty());
+                    ('t', *block)
+                }
+                Edit::EditPageImage { index, change: pdfcraft_engine::ImageEdit::Delete, .. } => ('i', *index),
+                Edit::DeleteContent { index, .. } => ('a', *index),
+                other => panic!("unexpected {}", other.label().wording),
+            })
+            .collect();
+        assert_eq!(order, [('t', 3), ('t', 1), ('i', 0), ('a', 2), ('a', 0)]);
+    }
+
+    #[test]
+    fn one_object_deletes_with_its_own_edit_and_none_with_nothing() {
+        assert!(matches!(delete_edit(2, vec![t(ObjectKind::Image, 4)]), Some(Edit::EditPageImage { page: 2, index: 4, .. })));
+        assert!(delete_edit(0, Vec::new()).is_none());
+    }
+}

crates/ui-egui/tests/it/editing.rs

@@ -4258,6 +4258,30 @@ fn an_ordinary_paragraph_drag_refusal_never_rewrites_the_text() {
     assert!(h.state().toast.as_ref().unwrap().0.contains("Text used as a clipping path cannot be moved with this selection."));
 }
 
+/// A delete the engine refuses (text used as a clipping path) leaves the document as it was and
+/// keeps the selection, so the user can still move or nudge what they had selected.
+#[test]
+fn a_refused_delete_keeps_the_object_selection() {
+    let content = "q BT 4 Tr /F1 12 Tf 60 320 Td (Clipping text) Tj ET Q";
+    let mut h = paragraph_drag_harness(paragraph_drag_fixture(content, 0, 1), 0);
+    let id = h.state().views[0].id;
+    let (generation, bytes) = {
+        let doc = h.state().session.get(id).unwrap();
+        (doc.edit_generation(), doc.bytes.clone())
+    };
+    // An area selection from empty page space around the paragraph.
+    let (center, _) = paragraph_drag_points(&h, "Clipping text", [0.0, 0.0]);
+    drag(&mut h, center - egui::vec2(60.0, 25.0), center + egui::vec2(60.0, 25.0));
+    h.get_by_label("1 object selected");
+    h.key_press(Key::Delete);
+    h.run_steps(4);
+    let doc = h.state().session.get(id).unwrap();
+    assert_eq!((doc.edit_generation(), &doc.bytes), (generation, &bytes), "the refused delete changed nothing");
+    assert!(doc.can_undo().is_none());
+    assert!(h.state().toast.is_some(), "the refusal is reported");
+    h.get_by_label("1 object selected");
+}
+
 #[test]
 fn an_ordinary_paragraph_drag_cannot_reuse_an_index_after_an_edit() {
     let content = "BT /F1 12 Tf 60 120 Td (Discard) Tj ET BT /F1 12 Tf 60 320 Td (Moving alpha) Tj ET BT /F1 12 Tf 60 220 Td (Keep here) Tj ET";
@@ -6019,3 +6043,33 @@ fn mode_tabs_keep_the_hand_over_a_paragraph_scrolled_under_them() {
     click_at(&mut h, convert);
     assert_eq!(h.state().mode, pdfcraft_ui_egui::Mode::Convert, "the tab takes the click, not the paragraph's editor");
 }
+
+/// A paragraph selected by its frame goes with one Delete (or Backspace), as in Acrobat, instead
+/// of being emptied a typed character at a time, and undo brings it back.
+#[test]
+fn a_paragraph_selected_by_its_frame_deletes_with_one_key() {
+    for key in [Key::Delete, Key::Backspace] {
+        let mut h = harness(2, |_| {});
+        assert!(h.state_mut().execute("edit.edit_text"));
+        h.run_steps(2);
+        let id = h.state().views[0].id;
+        let blocks = |h: &Harness<'static, PdfCraftApp>| h.state().session.get(id).unwrap().text_blocks(0);
+        let r = h.state().views[0].page_screen_rect(0).expect("on screen");
+        let k = r.width() / 200.0;
+        let screen = |x: f64, y: f64| egui::pos2(r.left() + x as f32 * k, r.top() + (300.0 - y as f32) * k);
+        let b = blocks(&h)[0].clone();
+        click_at(&mut h, screen((b.rect[0] + b.rect[2]) / 2.0, (b.rect[1] + b.rect[3]) / 2.0));
+        assert!(h.state().views[0].line_editor.is_some(), "a click on the text opens it for typing");
+        click_at(&mut h, screen((b.rect[0] + b.rect[2]) / 2.0, b.rect[3]) - egui::vec2(0.0, 4.0));
+        assert!(h.state().views[0].line_editor.is_none(), "the frame selects the box");
+        press(&mut h, Modifiers::NONE, key);
+        assert!(blocks(&h).is_empty(), "{key:?} deletes the whole paragraph: {:?}", blocks(&h));
+        assert!(h.state().views[0].line_editor.is_none(), "no empty editor is left behind");
+        assert!(h.query_all_by_label_contains("object selected").next().is_none(), "the deleted paragraph is no longer selected");
+        assert_eq!(h.state().session.get(id).unwrap().text_blocks(1)[0].text, "Page 2", "the next page keeps its text");
+        assert_eq!(h.state().session.get(id).unwrap().info.pages.len(), 2, "Delete removed the paragraph, not a page");
+        assert!(h.state_mut().execute("edit.undo"));
+        h.run_steps(2);
+        assert_eq!(blocks(&h).iter().map(|b| b.text.as_str()).collect::<Vec<_>>(), ["Page 1"], "undo restores it");
+    }
+}

parity/acrobat-features.toml

@@ -2202,8 +2202,8 @@ milestone = "M11"
 status = "partial"
 commands = ["edit.edit_text"]
 tools = ["object_list", "object_move"]
-evidence = ["crates/ui-egui/tests/it/object_selection.rs::marquee_and_mixed_group_drag_move_once_and_undo_together", "crates/automation/tests/it/automation.rs::mixed_objects_move_through_tools_with_generation_and_one_undo", "crates/edit/src/tests.rs::group_moves_preserve_glyph_bytes_and_unselected_text_state", "crates/engine/src/tests.rs::mixed_object_moves_are_one_undo_step_and_survive_save_reopen"]
-notes = "Same-page mixed selection (#844): Shift/Ctrl/Command-click toggles, empty-space marquee (additive with modifiers), drag previews and one atomic undo step for existing paragraphs, Image/Form XObjects and added text/images. Source glyph bytes, fonts and kerning retained; unselected text and shared Form resources stay put. Generation-scoped references with optional automation guard; count and geometry bounded; unsupported vertical/clipping text refused without partial changes. Still missing: arbitrary paths, inline images, cross-page movement, group resizing, arrange/align and a general object editor. See docs/editing-multiple-objects.md."
+evidence = ["crates/ui-egui/tests/it/object_selection.rs::marquee_and_mixed_group_drag_move_once_and_undo_together", "crates/automation/tests/it/automation.rs::mixed_objects_move_through_tools_with_generation_and_one_undo", "crates/edit/src/tests.rs::group_moves_preserve_glyph_bytes_and_unselected_text_state", "crates/engine/src/tests.rs::mixed_object_moves_are_one_undo_step_and_survive_save_reopen", "crates/ui-egui/tests/it/editing.rs::a_paragraph_selected_by_its_frame_deletes_with_one_key"]
+notes = "Same-page mixed selection (#844): Shift/Ctrl/Command-click toggles, empty-space marquee (additive with modifiers), drag previews and one atomic undo step for existing paragraphs, Image/Form XObjects and added text/images. Source glyph bytes, fonts and kerning retained; unselected text and shared Form resources stay put. Delete or Backspace removes the selection (a paragraph selected by its frame, or a group) as one undo step. Generation-scoped references with optional automation guard; count and geometry bounded; unsupported vertical/clipping text refused without partial changes. Still missing: arbitrary paths, inline images, cross-page movement, group resizing, arrange/align and a general object editor. See docs/editing-multiple-objects.md."
 
 [[feature]]
 id = "edit.object-properties"