327412 2026-10-13 09:21:10 -0700 [GTK][WPE] Input method delete-surrounding is documented in characters but counts UTF-16 code units 2026-10-19 05:35:21 -0700 1 1 1 Unclassified WebKit WPE WebKit WebKit Nightly Build Unspecified Unspecified RESOLVED FIXED https://bugs.webkit.org/show_bug.cgi?id=205716 https://bugs.webkit.org/show_bug.cgi?id=326818 https://bugs.webkit.org/show_bug.cgi?id=326817 https://bugs.webkit.org/show_bug.cgi?id=250208 https://bugs.webkit.org/show_bug.cgi?id=327414 https://bugs.webkit.org/show_bug.cgi?id=327694 P2 Normal --- 1 spena fujii alex aperez bugs-noreply cgarcia fujii oldest_to_newest 2263252 0 spena 2026-10-13 09:21:10 -0700 The delete-surrounding signal of WebKitInputMethodContext and WPEInputMethodContext documents offset and n_chars as characters. WebPage::deleteSurrounding() counts UTF-16 code units, and has done since the signal was added (bug 205716). The two only differ outside the Basic Multilingual Plane, for example with emoji. With the caret after "a😀": - delete-surrounding(-1, 1) deletes nothing: it covers half of the emoji's surrogate pair. - delete-surrounding(-2, 2) deletes the emoji. A delete that would start before the text depends on the code units too: after "a😀", (-4, 4) deletes nothing; after "aa😀", it deletes everything. Two more behaviours are not documented, and input methods rely on them: - The offset is counted from the start of the selection, and the delete can reach into the selection. - A count of 0 moves the caret by offset. Input method code in use counts in different units. wpe-android forwards Android's counts, which are UTF-16 code units, and we know of at least one other embedder that counts UTF-16 code units. The Wayland text-input-v1 backend converts to code points. The text-input-v3 backend passes bytes (bug 326818). Proposal: document UTF-16 code units, the selection start and the zero-count caret move. That matches what WebKit does today and changes no behaviour. Then make the Wayland backends convert to UTF-16 code units. Changing the behaviour to code points would break the embedders that count UTF-16 code units. 2265926 1 fujii 2026-10-18 22:38:00 -0700 Pull request: https://github.com/WebKit/WebKit/pull/77486 2265982 2 ews-feeder 2026-10-19 05:35:17 -0700 Committed 324121@main (c8f1f0f55c5f): <https://commits.webkit.org/324121@main> Reviewed commits have been landed. Closing PR #77486 and removing active labels.