Fix bug in LineEdit

base/repl/LineEdit.jl

@@ -258,15 +258,15 @@ function common_prefix(completions)
     c1 = completions[1]
     isempty(c1) && return ret
     i = 1
-    cc, nexti = c1, 2
+    cc, nexti = iterate(c1, i)
     while true
         for c in completions
             (i > endof(c) || c[i] != cc) && return ret
         end
         ret = string(ret, cc)
         i >= endof(c1) && return ret
         i = nexti
-        cc, nexti = c1, i+1
+        cc, nexti = iterate(c1, i)
     end
 end
 

test/repl.jl

@@ -60,6 +60,14 @@ fake_repl() do stdin_write, stdout_read, repl
     notify(b)
     wait(c)
 
+    # Give ourselves a generous timer here, just to prevent
+    # this causing e.g. a CI hang when there's something unexpected
+    # in the output.
+    t = Timer(200) do t
+        isopen(t) || return
+        error("Stuck waiting for repl test")
+    end
+
     # Latex completions
     write(stdin_write, "\x32\\alpha\t")
     readuntil(stdout_read, "α")
@@ -212,10 +220,6 @@ fake_repl() do stdin_write, stdout_read, repl
     # Test down arrow to go back to history
     # populate history with a trivial input
 
-    t = Timer(10) do t
-        isopen(t) || return
-        error("Stuck waiting for history test")
-    end
     s1 = "12345678"; s2 = "23456789"
     write(stdin_write, s1, '\n')
     readuntil(stdout_read, s1)