M3: a link without a position keeps the reader's place (ISO 32000-2 §12.3.2.2)

A /XYZ destination with a null (or unusable) left or top went to the top of the
target page. ISO 32000-2 §12.3.2.2 says a null value keeps the current one, and
Acrobat Reader, observed on a synthetic two-page fixture at 400 %, keeps the
user-space point at the window's top-left on the new page at the same zoom.
CAD exports (WSCAD) write every cross-reference as [page /XYZ null null 0], so
following one zoomed in landed on the sheet's title row instead of where the
reader was looking.

go_to_dest now reads the place at the window's top-left before the jump and
uses it for the null coordinates, along each axis the page overflows; a page
that fits keeps the layout's own placement. Null /FitH top and /FitV left
still go to the page edge.

Tests: a unit test (zoomed, partly given, view turned a quarter, page that
fits) and an end-to-end click on such a link at 400 %, both seen failing with
the fix reverted. The malformed-bookmark case in
bookmark_destinations_scroll_to_their_position now expects the kept place, as
DestView documents unusable operands as null.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
This commit is contained in:
Lcoding15
2026-10-23 20:41:06 +02:00
co-authored by Claude Opus 5.5
parent aea5e78e66
commit 21bbae39b9
3 changed files with 131 additions and 11 deletions
+2 -2
View File
@@ -1178,8 +1178,8 @@ milestone = "M3"
status = "shipped"
commands = []
tools = ["link_open"]
evidence = ["crates/ui-egui/tests/it/view.rs::clicking_a_link_goes_to_its_destination", "crates/ui-egui/tests/it/view.rs::link_destinations_scroll_to_their_position", "crates/render/src/inspect.rs::bookmarks_and_links_keep_their_destination_view", "crates/render/src/inspect.rs::links_read_bounded_local_remote_go_to_actions", "crates/automation/tests/it/automation.rs::local_gotor_link_open_applies_destinations_and_honors_root", "crates/ui-egui/tests/it/document_links.rs::a_local_gotor_link_opens_in_a_tab_and_applies_its_destination", "crates/ui-egui/tests/it/document_links.rs::an_absolute_gotor_waits_for_consent_and_keeps_its_destination_across_tabs", "crates/ui-egui/tests/it/document_links.rs::cancelling_an_absolute_gotor_by_button_escape_or_dismissal_changes_nothing", "crates/automation/tests/it/automation.rs::absolute_gotor_consent_does_not_bypass_validation_or_passwords", "crates/render/src/inspect.rs::launch_actions_that_name_a_pdf_open_it_like_a_remote_link", "crates/automation/tests/it/automation.rs::a_launch_link_to_a_pdf_opens_it_like_a_remote_link"]
notes = "GoTo and URI links plus local-PDF GoToR links: source-relative or local absolute /F paths, /UF preferred in file-spec dictionaries, explicit numeric page/view destinations, and internal tabs. Absolute local GoToR targets require desktop Allow/Cancel confirmation or an explicit allow_absolute opt-in in link_open; relative links open normally. link_open honors --root. Named remote destinations open at default view with a warning; /NewWindow is a tab hint. A Launch action whose /F names a .pdf file (and has no /Win launch parameters) opens that PDF the same way, backslash separators read as / (#4168); URL/network file systems, GoToE, other Launch actions and other actions are not executed. Same-document destinations retain their supported /XYZ, /Fit, /FitH, /FitV and /FitR views; /FitB* is read as whole-page fit."
evidence = ["crates/ui-egui/tests/it/view.rs::clicking_a_link_goes_to_its_destination", "crates/ui-egui/tests/it/view.rs::link_destinations_scroll_to_their_position", "crates/ui-egui/tests/it/view.rs::a_link_without_a_position_keeps_the_place_on_the_next_page", "crates/ui-egui/src/canvas.rs::a_null_xyz_coordinate_keeps_the_readers_place_on_the_new_page", "crates/render/src/inspect.rs::bookmarks_and_links_keep_their_destination_view", "crates/render/src/inspect.rs::links_read_bounded_local_remote_go_to_actions", "crates/automation/tests/it/automation.rs::local_gotor_link_open_applies_destinations_and_honors_root", "crates/ui-egui/tests/it/document_links.rs::a_local_gotor_link_opens_in_a_tab_and_applies_its_destination", "crates/ui-egui/tests/it/document_links.rs::an_absolute_gotor_waits_for_consent_and_keeps_its_destination_across_tabs", "crates/ui-egui/tests/it/document_links.rs::cancelling_an_absolute_gotor_by_button_escape_or_dismissal_changes_nothing", "crates/automation/tests/it/automation.rs::absolute_gotor_consent_does_not_bypass_validation_or_passwords", "crates/render/src/inspect.rs::launch_actions_that_name_a_pdf_open_it_like_a_remote_link", "crates/automation/tests/it/automation.rs::a_launch_link_to_a_pdf_opens_it_like_a_remote_link"]
notes = "GoTo and URI links plus local-PDF GoToR links: source-relative or local absolute /F paths, /UF preferred in file-spec dictionaries, explicit numeric page/view destinations, and internal tabs. Absolute local GoToR targets require desktop Allow/Cancel confirmation or an explicit allow_absolute opt-in in link_open; relative links open normally. link_open honors --root. Named remote destinations open at default view with a warning; /NewWindow is a tab hint. A Launch action whose /F names a .pdf file (and has no /Win launch parameters) opens that PDF the same way, backslash separators read as / (#4168); URL/network file systems, GoToE, other Launch actions and other actions are not executed. Same-document destinations retain their supported /XYZ, /Fit, /FitH, /FitV and /FitR views; /FitB* is read as whole-page fit. A null /XYZ left or top keeps the reader's place, as ISO 32000-2 §12.3.2.2 says and Acrobat Reader was observed to do (synthetic fixture): the user-space point at the window's top-left stays there on the target page at the same zoom, along each axis the page overflows; CAD exports (WSCAD) write every cross-reference this way. Null /FitH top and /FitV left still go to the page edge."
[[feature]]
id = "view.annotation-hover"