functests: Replace execute with either command or feed_command

Hope this will make people using feed_command less likely: this hides bugs.
Already found at least two:

1. msgpackparse() will show internal error: hash_add() in case of duplicate
   keys, though it will still work correctly. Currently silenced.
2. ttimeoutlen was spelled incorrectly, resulting in option not being set when
   expected. Test was still functioning somehow though. Currently fixed.

1 files changed, 15 insertions, 11 deletions

diff --git a/test/functional/legacy/function_sort_spec.lua b/test/functional/legacy/function_sort_spec.lua
index 1b65f1ce95..12875460e0 100644
--- a/test/functional/legacy/function_sort_spec.lua
+++ b/test/functional/legacy/function_sort_spec.lua
@@ -1,10 +1,11 @@
 local helpers = require('test.functional.helpers')(after_each)
-local clear = helpers.clear
+
 local eq = helpers.eq
+local neq = helpers.neq
 local eval = helpers.eval
-local execute = helpers.execute
+local clear = helpers.clear
+local source = helpers.source
 local exc_exec = helpers.exc_exec
-local neq = helpers.neq
 
 describe('sort', function()
   before_each(clear)
@@ -31,14 +32,17 @@ describe('sort', function()
   end)
 
   it('ability to call sort() from a compare function', function()
-    execute('func Compare1(a, b) abort')
-    execute([[call sort(range(3), 'Compare2')]])
-    execute('return a:a - a:b')
-    execute('endfunc')
-
-    execute('func Compare2(a, b) abort')
-    execute('return a:a - a:b')
-    execute('endfunc')
+    source([[
+      function Compare1(a, b) abort
+        call sort(range(3), 'Compare2')
+        return a:a - a:b
+      endfunc
+
+      function Compare2(a, b) abort
+        return a:a - a:b
+      endfunc
+    ]])
+
     eq({1, 3, 5}, eval("sort([3, 1, 5], 'Compare1')"))
   end)