fix(repl): prevent wrong-type-argument stringp nil

using chicken scheme 5.4.0 and geiser i was getting this
message repeatedly after every expression entered in repl

geiser-repl--output-filter: Wrong type argument: stringp, nil

in my case (geiser-con--connection-debug-prompt geiser-repl--connection)
evaluated to nil causing string-match-p to error out

(defun geiser-repl--matches-prompt-p (txt) ...
  txt was found to be the empty string most times ""

essential reduces to (string-match-p nil "")

so put some conditional pieces for txt is not a string,
if string is empty , no point checking since not a prompt

just use conjunction and to prevent string-match-p on nil on both
prompts
and use disjunction or to get next prompt type if first failed to match

thnaks

1 files changed, 7 insertions, 6 deletions

diff --git a/elisp/geiser-repl.el b/elisp/geiser-repl.el
index c43b9b2..1d130e5 100644
--- a/elisp/geiser-repl.el
+++ b/elisp/geiser-repl.el
@@ -586,12 +586,13 @@ to standard output face."
                               geiser-repl--last-output-end)))
 
 (defun geiser-repl--matches-prompt-p (txt)
-  (or (string-match-p
-       (geiser-con--connection-prompt geiser-repl--connection)
-       txt)
-      (string-match-p
-       (geiser-con--connection-debug-prompt geiser-repl--connection)
-       txt)))
+  (cond
+   ((not (stringp txt)) nil) 
+   ((string-empty-p txt) nil)
+   (t (or (let ((prompt1 (geiser-con--connection-prompt geiser-repl--connection)))
+            (and prompt1 (string-match-p prompt1 txt)))
+          (let ((prompt2 (geiser-con--connection-debug-prompt geiser-repl--connection)))
+            (and prompt2 (string-match-p prompt2 txt)))))))
 
 (defun geiser-repl--output-filter (txt)
   (when (geiser-repl--find-output-region) (geiser-repl--treat-output-region))