[nongnu] elpa/geiser-chicken 365aefadf7 1/2: Fix: current-environment-completions

[ELPA Syncer]

branch: elpa/geiser-chicken
commit 365aefadf751b8ec8194dc1e3cf4fc6e4c3386f8
Author: Lou Woell <lou.woell@posteo.de>
Commit: Lou Woell <lou.woell@posteo.de>

    Fix: current-environment-completions
    
    Check string length before calling `substring=?`
---
 src/geiser/chicken5.scm | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/geiser/chicken5.scm b/src/geiser/chicken5.scm
index 8bca81180b..31ce3cc509 100644
--- a/src/geiser/chicken5.scm
+++ b/src/geiser/chicken5.scm
@@ -281,7 +281,8 @@
   (define (current-environment-completions prefix)
     (let ((size (string-length prefix)))
       (filter
-       (lambda (candidate) (substring=? prefix candidate 0 0 size))
+       (lambda (candidate) (and (< size (string-length candidate))
+                           (substring=? prefix candidate 0 0 size)))
        (map (o symbol->string car) (##sys#current-environment)))))
 
   (define (apropos-completions prefix)