apply path assertions to existing path related commands

palps.rkt

@@ -121,45 +121,50 @@
       (session))))
 
 (define (session)
-  (display "palps > ")
-  (flush-output)
+  (with-handlers
+    ([exn:fail:contract:illegal-path?
+      (λ (exn)
+        (displayln "cannot traverse higher than root"))])
 
-  (match (regexp-match #px"(\\w+)\\s*(.*)"
-                       (read-line (current-input-port) 'any))
-    [(list _ "ls" _)
-     (for-each (λ (p) (displayln (path->string p)))
-               (directory-list))
-     (flush-output)]
+    (display "palps > ")
+    (flush-output)
 
-    [(list _ "ed" name)
-     (let ([path (build-path (current-directory)
-                             (string->path-element name))])
-       (let ([path (if (file-exists? path)
-                       (ed (our-make-temporary-file path))
+    (match (regexp-match #px"(\\w+)\\s*(.*)"
+                         (read-line (current-input-port) 'any))
+      [(list _ "ls" _)
+       (for-each (λ (p) (displayln (path->string p)))
+                 (directory-list))
+       (flush-output)]
+
+      [(list _ "ed" name)
+       (assert-confined-to-call-dir name)
+
+       (let ([path (if (file-exists? name)
+                       (ed (our-make-temporary-file name))
                        (ed))])
-         (copy-file path name #:exists-ok? #t)))]
+         (copy-file path name #:exists-ok? #t))]
 
-    [(list _ "rm" name)
-     (let ([path (build-path (current-directory)
-                             (string->path-element name))])
-       (if (file-exists? path)
-           (delete-file path)
+      [(list _ "rm" name)
+       (assert-confined-to-call-dir name)
+
+       (if (file-exists? name)
+           (delete-file name)
            (displayln "file does not exist"))
 
-       (flush-output))]
+       (flush-output)]
 
-    [(or (list _ "bye" _)
-         (list _ "b" _)
-         (list _ "quit" _)
-         (list _ "q" _))
-     (displayln "goodbye")
-     (flush-output)
-     (exit)]
+      [(or (list _ "bye" _)
+           (list _ "b" _)
+           (list _ "quit" _)
+           (list _ "q" _))
+       (displayln "goodbye")
+       (flush-output)
+       (exit)]
 
-    [else
-     (displayln "no such command")
-     (flush-output)])
+      [else
+       (displayln "no such command")
+       (flush-output)]))
 
   (session))
 
-(session-startup)
+;(session-startup)