editmerge: properly quote variables

editmerge: properly quote variables

Previously, files with spaces would break editmerge.

--- a/contrib/editmerge	Thu Oct 15 01:09:58 2015 -0700
+++ b/contrib/editmerge	Sat Oct 17 15:48:14 2015 -0700
@@ -10,23 +10,23 @@
 # editmerge.check=changed
 # editmerge.premerge=keep
 
-FILE=$1
+FILE="$1"
 
 getlines() {
-  grep -n "^<<<<<<" $FILE | cut -f1 -d:
+  grep -n "^<<<<<<" "$FILE" | cut -f1 -d:
 }
 
 # editor preference loosely based on https://mercurial-scm.org/wiki/editor
 # hg showconfig is at the bottom though, since it's slow to run (0.15 seconds)
-ED=$HGEDITOR
+ED="$HGEDITOR"
 if [ "$ED" = "" ] ; then
-  ED=$VISUAL
+  ED="$VISUAL"
 fi
 if [ "$ED" = "" ] ; then
-  ED=$EDITOR
+  ED="$EDITOR"
 fi
 if [ "$ED" = "" ] ; then
-  ED=$(hg showconfig ui.editor)
+  ED="$(hg showconfig ui.editor)"
 fi
 if [ "$ED" = "" ] ; then
   echo "merge failed - unable to find editor"
@@ -34,22 +34,22 @@
 fi
 
 if [ "$ED" = "emacs" ] || [ "$ED" = "nano" ] || [ "$ED" = "vim" ] ; then
-  FIRSTLINE=$(getlines | head -n 1)
+  FIRSTLINE="$(getlines | head -n 1)"
   PREVIOUSLINE=""
 
   # open the editor to the first conflict until there are no more
   # or the user stops editing the file
   while [ ! "$FIRSTLINE" = "" ] && [ ! "$FIRSTLINE" = "$PREVIOUSLINE" ] ; do
-    $ED +$FIRSTLINE $FILE
-    PREVIOUSLINE=$FIRSTLINE
-    FIRSTLINE=$(getlines | head -n 1)
+    "$ED" "+$FIRSTLINE" "$FILE"
+    PREVIOUSLINE="$FIRSTLINE"
+    FIRSTLINE="$(getlines | head -n 1)"
   done
 else
-  $ED $FILE
+  $ED "$FILE"
 fi
 
 # get the line numbers of the remaining conflicts
-CONFLICTS=$(getlines | sed ':a;N;$!ba;s/\n/, /g')
+CONFLICTS="$(getlines | sed ':a;N;$!ba;s/\n/, /g')"
 if [ ! "$CONFLICTS" = "" ] ; then
   echo "merge failed - resolve the conflicts (line $CONFLICTS) then use 'hg resolve --mark'"
   exit 1