test: Rename meth_pcall to pcall_err

- Rename `meth_pcall`.
- Make `pcall_err` raise an error if the function does not fail.
- Add `vim.pesc()` to treat a string as literal where a Lua pattern is
  expected.

1 files changed, 3 insertions, 3 deletions

diff --git a/test/functional/api/server_requests_spec.lua b/test/functional/api/server_requests_spec.lua
index a20667de40..e275d8cd35 100644
--- a/test/functional/api/server_requests_spec.lua
+++ b/test/functional/api/server_requests_spec.lua
@@ -10,7 +10,7 @@ local ok = helpers.ok
 local meths = helpers.meths
 local spawn, merge_args = helpers.spawn, helpers.merge_args
 local set_session = helpers.set_session
-local meth_pcall = helpers.meth_pcall
+local pcall_err = helpers.pcall_err
 
 describe('server -> client', function()
   local cid
@@ -220,8 +220,8 @@ describe('server -> client', function()
     end)
 
     it('returns an error if the request failed', function()
-      eq({false, "Vim:Error invoking 'does-not-exist' on channel 3:\nInvalid method: does-not-exist" },
-         meth_pcall(eval, "rpcrequest(vim, 'does-not-exist')"))
+      eq("Vim:Error invoking 'does-not-exist' on channel 3:\nInvalid method: does-not-exist",
+         pcall_err(eval, "rpcrequest(vim, 'does-not-exist')"))
     end)
   end)