[Tarantool-patches] [PATCHv2 1/1] test: move helper functions to sep module in -e assert(false) test

[Leonid Vasiliev]

Hi! Thank you for the patch.

See several comments below:
- "test: move helper functions to sep module in -e assert(false) test".
   "sep" -> "separated"?

- I have the same questions as before 
(https://lists.tarantool.org/pipermail/tarantool-patches/2020-December/021871.html)

1) I think you don't need to introduce a "new version". I propose to
split this patch into 2 separate patches. First - increase the timeout,
second - move common code

On 30.12.2020 11:31, Artem Starshov wrote:
> Functions with timeout transferred to module
> test/app-tap/lua/process_timeout.lua for further
> using in other tests.
> 
> Before this version of test was already done,
> but by mistake older version was rebased on
> master.
> 
> Follows up #4983
> ---
>   .../gh-4983-tnt-e-assert-false-hangs.test.lua | 73 ++++---------------
>   test/app-tap/lua/process_timeout.lua          | 57 +++++++++++++++
>   test/app-tap/suite.ini                        |  2 +-
>   3 files changed, 73 insertions(+), 59 deletions(-)
>   create mode 100644 test/app-tap/lua/process_timeout.lua
> 
> diff --git a/test/app-tap/gh-4983-tnt-e-assert-false-hangs.test.lua b/test/app-tap/gh-4983-tnt-e-assert-false-hangs.test.lua
> index 61eeaa8c1..2978a6203 100755
> --- a/test/app-tap/gh-4983-tnt-e-assert-false-hangs.test.lua
> +++ b/test/app-tap/gh-4983-tnt-e-assert-false-hangs.test.lua
> @@ -1,70 +1,27 @@
>   #!/usr/bin/env tarantool
>   
> -local fiber = require('fiber')
> -local clock = require('clock')
> -local ffi = require('ffi')
> -local fio = require('fio')
> -local errno = require('errno')
> +-- Using io.popen and self written module process_timeout
> +-- in presence of the 'popen' built-in module because the
> +-- last one isn't available in 1.10
> +local process_timeout = require('process_timeout')
>   local tap = require('tap')
> +local fio = require('fio')
> +local ffi = require('ffi')
>   
>   --
>   -- gh-4983: tarantool -e 'assert(false)' hangs
>   --
>   
> --- For process_is_alive.
> -ffi.cdef([[
> -    int kill(pid_t pid, int sig);
> -]])
> -
> ----  Verify whether a process is alive.
> -local function process_is_alive(pid)
> -    local rc = ffi.C.kill(pid, 0)
> -    return rc == 0 or errno() ~= errno.ESRCH
> -end
> -
> ---- Returns true if process completed before timeout, false otherwise.
> -local function wait_process_completion(pid, timeout)
> -    local start_time = clock.monotonic()
> -    local process_completed = false
> -    while clock.monotonic() - start_time < timeout do
> -        if not process_is_alive(pid) then
> -            process_completed = true
> -            break
> -        end
> -        fiber.sleep(0.01)
> -    end
> -    return process_completed
> -end
> -
> ---- Open file on reading with timeout.
> -local function open_with_timeout(filename, timeout)
> -    local fh
> -    local start_time = clock.monotonic()
> -    while not fh and clock.monotonic() - start_time < timeout do
> -        fh = fio.open(filename, {'O_RDONLY'})
> -    end
> -    return fh
> -end
> -
> ---- Try to read from file with timeout with interval.
> -local function read_with_timeout(fh, timeout, interval)
> -    local data = ''
> -    local start_time = clock.monotonic()
> -    while #data == 0 and clock.monotonic() - start_time < timeout do
> -        data = fh:read()
> -        if #data == 0 then fiber.sleep(interval) end
> -    end
> -    return data
> -end
> -
>   local TARANTOOL_PATH = arg[-1]
>   local output_file = fio.abspath('out.txt')
>   local line = ('%s -e "assert(false)" > %s 2>&1 & echo $!'):
>           format(TARANTOOL_PATH, output_file)
> -local process_waiting_timeout = 30.0
> -local file_read_timeout = 30.0
> -local file_read_interval = 0.2
> -local file_open_timeout = 30.0
> +
> +-- Like a default timeout for `cond_wait` in test-run
> +local process_waiting_timeout = 60.0
> +local file_read_timeout = 60.0
> +local file_open_timeout = 60.0
> +local file_read_interval = 0.01
>   
>   local res = tap.test('gh-4983-tnt-e-assert-false-hangs', function(test)
>       test:plan(2)
> @@ -72,7 +29,7 @@ local res = tap.test('gh-4983-tnt-e-assert-false-hangs', function(test)
>       local pid = tonumber(io.popen(line):read('*line'))
>       assert(pid, 'pid of proccess can\'t be recieved')
>   
> -    local process_completed = wait_process_completion(pid,
> +    local process_completed = process_timeout.wait_process_completion(pid,
>               process_waiting_timeout)
>   
>       test:ok(process_completed,
> @@ -81,10 +38,10 @@ local res = tap.test('gh-4983-tnt-e-assert-false-hangs', function(test)
>       -- Kill process if hangs.
>       if not process_completed then ffi.C.kill(pid, 9) end
>   
> -    local fh = open_with_timeout(output_file, file_open_timeout)
> +    local fh = process_timeout.open_with_timeout(output_file, file_open_timeout)
>       assert(fh, 'error while opening ' .. output_file)
>   
> -    local data = read_with_timeout(fh, file_read_timeout, file_read_interval)
> +    local data = process_timeout.read_with_timeout(fh, file_read_timeout, file_read_interval)
>       test:like(data, 'assertion failed', 'assertion failure is displayed')
>   
>       fh:close()
> diff --git a/test/app-tap/lua/process_timeout.lua b/test/app-tap/lua/process_timeout.lua
> new file mode 100644
> index 000000000..141fb0e43
> --- /dev/null
> +++ b/test/app-tap/lua/process_timeout.lua
> @@ -0,0 +1,57 @@
> +local fiber = require('fiber')
> +local clock = require('clock')
> +local ffi = require('ffi')
> +local fio = require('fio')
> +local errno = require('errno')
> +
> +-- For process_is_alive.
> +ffi.cdef([[
> +    int kill(pid_t pid, int sig);
> +]])
> +
> +---  Verify whether a process is alive.
> +local function process_is_alive(pid)
> +    local rc = ffi.C.kill(pid, 0)
> +    return rc == 0 or errno() ~= errno.ESRCH
> +end
> +
> +--- Returns true if process completed before timeout, false otherwise.
> +local function wait_process_completion(pid, timeout)
> +    local start_time = clock.monotonic()
> +    local process_completed = false
> +    while clock.monotonic() - start_time < timeout do
> +        if not process_is_alive(pid) then
> +            process_completed = true
> +            break
> +        end
> +    end
> +    return process_completed
> +end
> +
> +--- Open file on reading with timeout.
> +local function open_with_timeout(filename, timeout)
> +    local fh
> +    local start_time = clock.monotonic()
> +    while not fh and clock.monotonic() - start_time < timeout do
> +        fh = fio.open(filename, {'O_RDONLY'})
> +    end
> +    return fh
> +end
> +
> +--- Try to read from file with timeout with interval.
> +local function read_with_timeout(fh, timeout, interval)
> +    local data = ''
> +    local start_time = clock.monotonic()
> +    while #data == 0 and clock.monotonic() - start_time < timeout do
> +        data = fh:read()
> +        if #data == 0 then fiber.sleep(interval) end
> +    end
> +    return data
> +end
> +
> +return {
> +    process_is_alive = process_is_alive,

2) No external function currently uses this function.
I suggest removing it from the interface.

> +    wait_process_completion = wait_process_completion,
> +    open_with_timeout = open_with_timeout,
> +    read_with_timeout = read_with_timeout
> +}
> diff --git a/test/app-tap/suite.ini b/test/app-tap/suite.ini
> index 2f16128f9..6e27f88d6 100644
> --- a/test/app-tap/suite.ini
> +++ b/test/app-tap/suite.ini
> @@ -1,7 +1,7 @@
>   [default]
>   core = app
>   description = application server tests (TAP)
> -lua_libs = lua/require_mod.lua lua/serializer_test.lua
> +lua_libs = lua/require_mod.lua lua/serializer_test.lua lua/process_timeout.lua
>   is_parallel = True
>   pretest_clean = True
>   use_unix_sockets_iproto = True
>