1184533 - [IMM] ASSERTION: offset is less than cursorPosition!: 'offset >= cursorPosition'

Status: RESOLVED FIXED

(Core :: Widget: Win32, defect)

Description

[Masayuki Nakano [:masayuki] (he/him)(JST, +0900)]

When I type first character in empty editor in IMM mode, I see this assertion:
ASSERTION: offset is less than cursorPosition!: 'offset >= cursorPosition'

Looks like that this assertion and following code ensure that the offset is in composition string. However, this must be a simple mistake.

Comment 1

[Masayuki Nakano [:masayuki] (he/him)(JST, +0900)]

https://treeherder.mozilla.org/#/jobs?repo=try&revision=0303b7edac02

Comment 2

[Masayuki Nakano [:masayuki] (he/him)(JST, +0900)]

Attachment: Rewrite range check in aOffset of nsIMM32Handler::GetCharacterRectOfSelectedTextAt()

Comment 3

[Masayuki Nakano [:masayuki] (he/him)(JST, +0900)]

Comment on attachment 8635107 [details] [diff] [review]
Rewrite range check in aOffset of nsIMM32Handler::GetCharacterRectOfSelectedTextAt()

Let's check if the querying offset is in composition string or selected string with clearer code. We can return any character's rect (without e10s), the caller (or active IME) must be buggy if the offset is out of the composition/selected string.

Comment 4

[Masayuki Nakano [:masayuki] (he/him)(JST, +0900)]

Comment on attachment 8635107 [details] [diff] [review]
Rewrite range check in aOffset of nsIMM32Handler::GetCharacterRectOfSelectedTextAt()

Oops, I realized that this could be simpler. if aOffset is 0, we don't need complicated check.

Comment 5

[Masayuki Nakano [:masayuki] (he/him)(JST, +0900)]

https://treeherder.mozilla.org/#/jobs?repo=try&revision=a411a9604a35

Comment 6

[Masayuki Nakano [:masayuki] (he/him)(JST, +0900)]

https://treeherder.mozilla.org/#/jobs?repo=try&revision=ea0dc2815cc9

Comment 7

[Masayuki Nakano [:masayuki] (he/him)(JST, +0900)]

Attachment: Rewrite handling of aOffset in nsIMM32Handler::GetCharacterRectOfSelectedTextAt()

When there is a composition, normal selection is the caret in the composition string. So, the method's base offset should be computed with mIsComposing.

If the selected length (or composition string when mIsComposing == true) is collapsed and the offset is same as the caret offset, we should return caret rect. Otherwise, the character rect at the offset.

Comment 8

[Masayuki Nakano [:masayuki] (he/him)(JST, +0900)]

Attachment: Rewrite range check in aOffset of nsIMM32Handler::GetCharacterRectOfSelectedTextAt()

Merged with the latest m-c.

Comment 9

[Masayuki Nakano [:masayuki] (he/him)(JST, +0900)]

url:        https://hg.mozilla.org/integration/mozilla-inbound/rev/e7549c25cfcd77273abd493fa923183367fbfc40
changeset:  e7549c25cfcd77273abd493fa923183367fbfc40
user:       Masayuki Nakano <[e-mail]>
date:       Sun Jul 26 12:29:47 2015 +0900
description:
Bug 1184533 Rewrite range check in aOffset of nsIMM32Handler::GetCharacterRectOfSelectedTextAt() r=emk

Comment 10

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/mozilla-central/rev/e7549c25cfcd