CSS error reporting sometimes off by one #3625
Description
See #3582 (comment).
Running the app at the bottom produces the error below, where the error reporting is off by one.
See the line above the panel and the code lines in the code snippet printed.
Error in stylesheet:
/Users/davep/develop/python/textual-upstream/sandbox/foo.py, CSSErrorApp.CSS:1:4
╭────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╮
│ 1 │ │
│ ❱ 2 │ : │
│ 3 │
╰────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────╯
• Expected one of 'comment line', 'comment start', 'selector start', 'selector start class', 'selector start id', 'selector start universal', 'variable name', or 'whitespace'.
• Did you forget a semicolon at the end of a line?
from textual.app import App, ComposeResult
from textual.widgets import Label
class CSSErrorApp(App[None]):
CSS = """
:
"""
def compose(self) -> ComposeResult:
yield Label()
if __name__ == "__main__":
CSSErrorApp().run()