setline() will clear text property about vim

[chrisbra]

Well, I can only say this is done intentionally since v8.1.0690. The idea probably was that once you replace a line, all attached properties to it may no longer be valid, which I think makes sense.

[Yggdroot]

Although it was intentional, I can not see the advantage of it, but lots of disadvantages. Because I can not prevent the text properties defined by my plugin from being removed by others which use setline().

I don't think it make sense that the text property is removed after call setline(line('.'), getline('.')), the text is not changed in the user's view.

What is more, as I said above, Another reason, setline() won't clear extmarks set by nvim_buf_set_extmark() in neovim， where extmarks in neovim is equivalent to text property in vim.

[Shane-XB-Qian]

looks it make sense if the text was changed. but I am curious you said the by D then it would be remained?

…

-- shane.xb.qian

[chrisbra]

What is more, as I said above, Another reason, setline() won't clear extmarks set by nvim_buf_set_extmark() in neovim， where extmarks in neovim is equivalent to text property in vim.

I don't see how this relates to Vim. We don't have this: nvim_buf_set_extmark().

[Yggdroot]

looks it make sense if the text was changed. but I am curious you said the by D then it would be remained?
…
-- shane.xb.qian

call prop_type_add('aaa', {'highlight': 'Number'})
call prop_add(line('.'), 0, {'type':'aaa', 'text': 'test'})

[Yggdroot]

What is more, as I said above, Another reason, setline() won't clear extmarks set by nvim_buf_set_extmark() in neovim， where extmarks in neovim is equivalent to text property in vim.

I don't see how this relates to Vim. We don't have this: nvim_buf_set_extmark().

I mean in neovim's point of view, setline should not remove text property just like setline does not remove extmarks.

Another reason current behavior is thought to be buggy is : setline also removes zero-width text property.

vim/runtime/doc/textprop.txt

Lines 509 to 517 in c52a856

	3. When text changes *text-prop-changes*
	Vim will do its best to keep the text properties on the text where it was
	attached. When inserting or deleting text the properties after the change
	will move accordingly.
	When text is deleted and a text property no longer includes any text, it is
	deleted. However, a text property that was defined as zero-width will remain,
	unless the whole line is deleted.

However, a text property that was defined as zero-width will remain, unless the whole line is deleted.

[chrisbra]

However, a text property that was defined as zero-width will remain, unless the whole line is deleted.

I think this is essentially what setline does. It deletes the line and replaces it with a new one, even if it is empty.

[zeertzjq]

Maybe this can be made configurable as a flag of text properties? Similar to neovim/neovim#25767 but in the opposite way.

[Yggdroot]

However, a text property that was defined as zero-width will remain, unless the whole line is deleted.

I think this is essentially what setline does. It deletes the line and replaces it with a new one, even if it is empty.

Is it not the same with :
norm! 0D
then append some text ?

I think the whole line is deleted is like: norm! dd . setline just need to replace the content of the specified line of buffer.

[chrisbra]

I rather thought of making the behaviour of setline() configurable.

[habamax]

I rather thought of making the behaviour of setline() configurable.

How it would solve the issue then? There still will be setline() calls that would remove text properties:

Because I can not prevent the text properties defined by my plugin from being removed by others which use setline().

I think removal of text properties as of current implementation is expected.

[chrisbra]

I think removal of text properties as of current implementation is expected.

Yes, that is also my expectation, see also:

vim/runtime/doc/textprop.txt

Lines 534 to 538 in c52a856

	Text property columns are not updated or copied: ~
	- When setting the line with |setline()| or through an interface, such as Lua,
	Tcl or Python. Vim does not know what text got inserted or deleted.
	- With a command like `:move`, which takes a line of text out of context.

it looks like even :move drops the text properties.

There still will be setline() calls that would remove text properties

Well, would you expect the text-property to be still there after doing

:5d
:4put ='foobar'

? Once you remove the line and add a new line, how would do you know the attached text-property attached to that line is still valid?

[Shane-XB-Qian]

> looks it make sense if the text was changed. but I am curious you said the by D then it would be remained? > […](#) > -- shane.xb.qian ```vim call prop_type_add('aaa', {'highlight': 'Number'}) call prop_add(line('.'), 0, {'type':'aaa', 'text': 'test'}) ```

not sure why `D` was special.. // if delete by :delete, then it was removed too.

…

-- shane.xb.qian

[Yggdroot]

looks it make sense if the text was changed. but I am curious you said the by D then it would be remained? > … > -- shane.xb.qian vim call prop_type_add('aaa', {'highlight': 'Number'}) call prop_add(line('.'), 0, {'type':'aaa', 'text': 'test'})
not sure why D was special.. // if delete by :delete, then it was removed too.
…
-- shane.xb.qian

It is different.
:delete is the same as dd, not D

[Shane-XB-Qian]

yes, it is different, but the answer maybe as @chrisbra commented above, to D maybe it was intended to make it happy with instant edit. 🤷

[Yggdroot]

I think removal of text properties as of current implementation is expected.

Yes, that is also my expectation, see also:

vim/runtime/doc/textprop.txt

Lines 534 to 538 in c52a856

	Text property columns are not updated or copied: ~
	- When setting the line with |setline()| or through an interface, such as Lua,
	Tcl or Python. Vim does not know what text got inserted or deleted.
	- With a command like `:move`, which takes a line of text out of context.

it looks like even :move drops the text properties.

There still will be setline() calls that would remove text properties

Well, would you expect the text-property to be still there after doing

:5d
:4put ='foobar'

? Once you remove the line and add a new line, how would do you know the attached text-property attached to that line is still valid?

Actually, my expectation is :
for example,

call prop_type_add('aaa', {'highlight': 'Number'})
call prop_add(line('.'), 0, {'type':'aaa', 'text': 'test'})

call setline(line('.'), '') has the same effect as norm! 0D.

call prop_type_add('aaa', {'highlight': 'Number'})
call prop_add(line('.'), 1, {'type':'aaa', 'length': 0})

call setline(line('.'), '') has the same effect as norm! 0D.

Because However, a text property that was defined as zero-width will remain, unless the whole line is deleted.
I think setline is not delete line 3 and insert a new line after line 2, it is replacing line 3 with new text. Am I right?

[Shane-XB-Qian]

unless the whole line is deleted it was said for D 😅

[Yggdroot]

unless the whole line is deleted it was said for D 😅

I think it's dd

[Shane-XB-Qian]

i meant that statement was expressed why D was special.

[chrisbra]

I posted the link to the documentation already. It's simply not possible to retain the text property, because how should Vim know where you added some text?

call setline(1, 'You are a hero!')
cal prop_type_add('Highlight', #{highlight: 'Search'})
call prop_add(1, 11, {'end_col': 15, 'type': 'Highlight'})
" doesn't work, but would add an off by one error
call getline(1)->substitute('\<a\>', 'my', 'g')->setline(1) 

[Yggdroot]

Notice that my example is special, one is virtual text, the column is 0, another is 0-width.

call prop_type_add('aaa', {'highlight': 'Number'})
call prop_add(line('.'), 0, {'type':'aaa', 'text': 'test'})

call prop_type_add('aaa', {'highlight': 'Number'})
call prop_add(line('.'), 1, {'type':'aaa', 'length': 0})

:call setline(line('.'), '') will remove the virtual text, :norm! 0D won't.
Can we make their behavior the same?

[habamax]

:call setline(line('.'), '') will remove the virtual text, :norm! 0D won't.
Can we make their behavior the same?

If properties wouldn't be removed, then a lot of things would need to be changed internally...
You have a text property, then you changed a line and now it is invalid.

[habamax]

Now if the case is virtual text at the edges of the line -- it could be safe to preserve it, although I am not sure it worth the complexity it brings.

[Shane-XB-Qian]

Can we make their behavior the same?

the 'question' had been answered above.

…

-- shane.xb.qian

[Yggdroot]

Can we make their behavior the same?
the 'question' had been answered above.
…
-- shane.xb.qian

I don't think so.

[bfrg]

I would also expect setline() and setbufline() to remove any text-properties.

I think what you want is something like subbufline() that substitutes text in a line while preserving text-properties in that line, similar to the :substitute command. There's already an open feature request for #5632. Bram wasn't opposed to this idea, it just needs to be implemented. 😄

[Yggdroot]

In my view, :call setline(line('.'), '') and :norm! 0D do the same thing, why :norm! 0D don't remove the virtual-text column starts from 0 and the 0-width text property?

[chrisbra]

The effect might be the same, but it is not the same, it's essentially a :d followed by a :put.
There is also listener_add() not sure, if one can use it to save and restore text-properties.

The current behaviour is well documented, so let's close this as a duplicate of #5632 then.