NewCmdTask feeds the reader returned by its start func into a
bufio.Scanner, and Scanner.Scan panics with a nil pointer dereference
when that reader is nil. Two start funcs could produce one:
- newPtyTask's fallback for a failed StartPty returned a literal nil
reader, alongside an ExecCmd that was never started, so the intended
"fall back to a plain cmd task" never worked. This crashed lazygit on
Windows when using a custom pager with the main view zero-sized, e.g.
after pressing + twice to enter full-screen mode with a side panel
focused: ConPTY rejects zero dimensions, making StartPty fail.
- startCmdWithPipe returned nil when the pipe couldn't be created,
which the Unix pty fallback path can trigger, since a failed pty
start can leave the tty assigned to the command's stdout.
Make startCmdWithPipe never return a nil reader: when the pipe can't be
created, don't start the command at all and return an empty reader so
the task shuts down cleanly with the error in the log. Then route
newPtyTask's fallback through it, so a StartPty failure degrades to
running the command without a pty: the pager is lost, but the command's
output still renders.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
NewCmdTask feeds the reader returned by its start func straight into a
bufio.Scanner, whose Scan panics on a nil reader with a nil pointer
dereference. startCmdWithPipe returns exactly that when the pipe cannot
be created.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
