Ability to replace text while keeping TextArea history

[BongoKnight]

When you replace text in a TextArea with TextArea.text setter or with load_text, it could be great to not clean the history of the TextArea widget.

from textual.app import App, ComposeResult
from textual.widgets import Header, Footer, TextArea


class TextAreaApp(App):

    def compose(self) -> ComposeResult:
        """Create child widgets for the app."""
        yield Header()
        yield TextArea("Initial text", classes="maintext")
        yield Footer()
        
    
    def on_mount(self):
        textArea = self.query_one(TextArea)
        textArea.insert("Updated text with insert 1")
        textArea.text = "Updated text with load_text"
        textArea.clear()
        textArea.insert("Updated text with insert 2")


if __name__ == "__main__":
    app = TextAreaApp()
    app.run()

In this MRE I would like to be able to use Ctrl-Z in the TextArea and come back to the Updated text with insert 1 text.

[github-actions]

We found the following entries in the FAQ which you may find helpful:

• How can I select and copy text in a Textual app?
• How do I center a widget in a screen?

Feel free to close this issue if you found an answer in the FAQ. Otherwise, please give us a little time to review.

This is an automated reply, generated by FAQtory

[TomJGooding]

It makes sense to me that load_text will "clear the edit history" per the docs as you're loading a new document?

What problem would this solve rather than using the existing replace method?

[BongoKnight]

Thanks for pointing out this function that I missed.
However I found it quite confusing to use, to replace the whole document the syntax is quite complex (maybe once again I missed some property to access rapidly to the position of the end of the document...):

from textual.app import App, ComposeResult
from textual.widgets import Header, Footer, TextArea



class TextAreaApp(App):

    def compose(self) -> ComposeResult:
        """Create child widgets for the app."""
        yield Header()
        yield TextArea("Initial text", classes="maintext")
        yield Footer()
        
    
    def on_mount(self):
        textArea = self.query_one(TextArea)
        textArea.insert("Updated text with insert 1")
        textArea.text = "Updated text with load_text"
        textArea.replace("Updated with replace", (0,0), (textArea.document.line_count, len(textArea.document.get_line(textArea.document.line_count-1))))
        textArea.insert("Updated text with insert 2")


if __name__ == "__main__":
    app = TextAreaApp()
    app.run()

[TomJGooding]

This is slightly shorter:

            end=(text_area.document.line_count, len(text_area.document[-1])),

But perhaps a convenience "document end" property would be useful.

[TomJGooding]

A Document.end property was added in #4267 so will be in the next release. Hopefully this closes this issue?

[BongoKnight]

Yes it's perfect! Thanks a lot! 😊

[github-actions]

Don't forget to star the repository!

Follow @textualizeio for Textual updates.