Fix with-terminal to restore terminal state on exceptions

Message

The VM's exception propagation does not run dynamic-wind after-thunks, so an error inside with-terminal left the terminal in raw mode with alternate screen active. Add a guard inside the dynamic-wind thunk that manually restores the terminal before re-raising the exception.

Changed

 src/sigil/tui/terminal.sgl | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

Diff

src/sigil/tui/terminal.sglmodified

@@ -79,7 +79,17 @@

79

(terminal-raw-mode! #t)

80

(alternate-screen-on)

81

(terminal-write-raw (string-append esc "[?25l"))) ;; hide cursor

−82

thunk

+82

(lambda ()

+83

;; Guard catches exceptions and manually restores the terminal

+84

;; before re-raising. This is needed because the VM's exception

+85

;; propagation does not run dynamic-wind after-thunks.

+86

(guard (exn (#t

+87

(disable-mouse-tracking)

+88

(terminal-write-raw (string-append esc "[?25h"))

+89

(alternate-screen-off)

+90

(terminal-raw-mode! #f)

+91

(raise exn)))

+92

(thunk)))

93

(lambda ()

94

(disable-mouse-tracking)

95

(terminal-write-raw (string-append esc "[?25h")) ;; show cursor