update insertText logic when selection is not collapsed

[suilang]

Description
When I select a paragraph with different styles of text, for example, bold and plain, and then insert the letter q. What I want is to insert a non-bold letter.

Example
this is old code, the q is bold

this is new code, the q is normal

Context

Normally, when we insert the character q between unbold and bold, it is unbold. the style use position of anchor. but when selection is not collapsed, selection be set by focus or end of range.

The processing logic is inconsistent for different actions. also, the cursor should be placed at the starting position. If the deleted area has elements that cannot be deleted, like table, the cursor position will be incorrect

Checks

• The new code matches the existing patterns and styles.
• The tests pass with yarn test.
• The linter passes with yarn lint. (Fix errors with yarn fix.)
• The relevant examples still work. (Run examples with yarn start.)
• You've [added a changeset]

[changeset-bot]

🦋 Changeset detected

Latest commit: 0552d9e

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

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[dylans]

Thanks @suilang . I'm not sure if it matters here, but have you checked selecting in reverse to make sure we don't break due to the direction of the selection (some parts of the codebase are good about reversing the selection and some are not).

[suilang]

@dylans Thank reply. You mean selecting text from back to front? In there i use Range.start to get start point, it make sure that start is always brefore end point。

[imbolo]

@suilang @dylans
After this change，it throws an error when I select two lines and input any character.

select-two-line-and-input.mov

[TheSpyder]

The error is because with a selection like that the range start is inside the first paragraph. The paragraph is deleted and so the pointref is too. This doesn't happen when the pointref is based on end because by definition the end cursor position is just collapsed to the start of the range through deletion.

This PR gave me a bad feeling but I didn't have time to confirm whether it was a mistake. Thank you @imbolo for confirming it is. @dylans we need to revert.

I don't know if there's a nice way to fix OP's problem. Maybe a smarter way to pick whether to use the start or end ref? Or perhaps just store two point refs for start and end if start becomes null use the end.

[cmditch]

Also experiencing errors with this in production. We've reverted back to 0.72.3.

[dylans]

Reverted as noted above. Hopefully we can find a better solution for the issue identified in this original PR without breaking other behavior.

[suilang]

@TheSpyder @dylans I'm sorry it happened. like you say, the paragraph is deleted.

I still think the cursor should be placed at the starting position. As the picture above shows, The text style should be the same as before

I have fix this error, by store two point refs for start and end . like this,

and add test case describe the scene as I see it

I am not sure whether I should submit the PR again. I hope to get your opinion

[dylans]

@suilang it's ok, rich text editing is not easy. Feel free to raise a new PR with tests and we'll evaluate it.