[Tarantool-patches] [PATCH v4 8/8] test: use direct log module

[Oleg Babin]

Hi! Thanks for your patch. See several comments below.

On 28/05/2020 13:07, Cyrill Gorcunov wrote:
> To test if we can setup logging module before the box/cfg{}.

nit: `box.cfg{}`, not `box/cfg{}`
> 
> Part-of #689
> 
> Signed-off-by: Cyrill Gorcunov <gorcunov at gmail.com>
> ---
>   test/app-tap/logger.test.lua | 27 ++++++++++++++++++++++++---
>   1 file changed, 24 insertions(+), 3 deletions(-)
> 
> diff --git a/test/app-tap/logger.test.lua b/test/app-tap/logger.test.lua
> index 7bfa06e80..410220494 100755
> --- a/test/app-tap/logger.test.lua
> +++ b/test/app-tap/logger.test.lua
> @@ -1,23 +1,44 @@
>   #!/usr/bin/env tarantool
>   
>   local test = require('tap').test('log')
> -test:plan(24)
> +test:plan(27)
>   
>   -- gh-3946: Assertion failure when using log_format() before box.cfg()
>   local log = require('log')
>   log.log_format('plain')
>   
> +--
> +-- gh-689: Operate with logger via log module without calling box.cfg{}

As we've discussed it's better to add "negative" cases to tests.
There are examples, e.g. 
https://github.com/tarantool/tarantool/blob/master/test/app-tap/yaml.test.lua#L86

> +local json = require('json')
> +local filename = "1.log"
> +
> +log.cfg({log=filename, log_format='json', log_level=5})
> +local m = "info message"
> +
> +local file = io.open(filename)
> +while file:read() do
> +end
> +
> +log.info(m)
> +local line = file:read()
> +local message = json.decode(line)
> +file:close()
> +
> +test:is(type(message), 'table', "(log) json valid in log.info")
> +test:is(message.level, "INFO", "(log) check type info")
> +test:is(message.message, m, "(log) check message content")
> +log.log_format('plain')
> +
>   --
>   -- Check that Tarantool creates ADMIN session for #! script
>   --
> -local filename = "1.log"
>   local message = "Hello, World!"
>   box.cfg{
>       log=filename,
> +    log_format='plain',
>       memtx_memory=107374182,
>   }
>   local fio = require('fio')
> -local json = require('json')
>   local fiber = require('fiber')
>   local file = io.open(filename)
>   while file:read() do
>