[Rd] setRepositories() doesn't allow graceful cancellation from GUI menu (PR#13937)

[richcalaway at revolution-computing.com]

Full_Name: Richard  Calaway
Version: 2.9.2
OS: Windows Vista
Submission from: (NULL) (65.47.30.18)


If you call setRepositories(graphics=TRUE), or, equivalently, choose "Select
repositories..." from RGui's Packages menu, and then click "Cancel", you are
dropped to the command line menu. Choosing "Cancel" should drop you back to the
top-level prompt. Also, the command-line menu doesn't specify how to cancel. The
following patch clears up both problems:

Index: packages.R
===================================================================
--- packages.R  (revision 49504)
+++ packages.R  (working copy)
@@ -639,7 +639,7 @@
     }
 
     default <- a[["default"]]
-
+    nc <- length(default)
     if(length(ind)) res <- as.integer(ind)
     else {
         res <- integer(0L)
@@ -654,20 +654,19 @@
                                                    multiple = TRUE,
"Repositori
es"),
                              a[, 1L])
         }
-        if(!length(res)) {
+        else {
             ## text-mode fallback
             cat(gettext("--- Please select repositories for use in this
session
 ---\n"))
-            nc <- length(default)
             cat("", paste(seq_len(nc), ": ",
                           ifelse(default, "+", " "), " ", a[, 1L],
                           sep=""),
                 "", sep="\n")
-            cat(gettext("Enter one or more numbers separated by spaces\n"))
+            cat(gettext("Enter one or more numbers separated by spaces, or 0
to
 cancel\n"))
             res <- scan("", what=0, quiet=TRUE, nlines=1L)
-            if(!length(res) || (length(res) == 1L && !res[1L]))
-                return(invisible())
-            res <- res[1 <= res && res <= nc]
         }
+        if(!length(res) || (length(res) == 1L && !res[1L]))
+            return(invisible())
+        res <- res[1 <= res && res <= nc]
     }
     if(length(res)) {
         repos <- a[["URL"]]