Unit test – Can I load the library in Lua?

-- script. lua

local mp = require('mp')

-- script-tests.lua

describe('my script unit tests', function()
 local script = require('script')

 it('...', function()
 assert.is_true(true)
 end)
end)

-- script.lua

local plugin = {}
local mpv_loaded, mp = pcall(require,'mp')

plugin .mp = mp

-------------------------------------- -------------------------------
-- Stub MPV library for unit tests
if not mpv_loaded then
 plugin.mp = {}

 function plugin.mp.osd_message(message)
 plugin.mp.message = message
 end

 function plugin.mp.log(level, message)
 - stub
 end

 function plugin.mp.add_forced_key_binding(...)
 - stub
 end

 function plugin.mp.remove_key_binding(...)
 - stub
 end
end

 -------------------------------------------------- -------------------
-- Display message on screen.
function plugin:show_message(message)
 self.mp.osd_message (message)
end

return plugin 
-- script-tests.lua

describe('my script unit tests', function()
 local plugin = require('script')
< br /> it('...', function()
 message ='It is better to play than do nothing.'
 plugin:show_message(message)

 assert .is_same(plugin.mp.message, message)
 end)

end)

local mpv_loaded, mp = pcall (function() return require'mp' end)

if not mpv_loaded then
 - handle the bad require, in this case'mp' holds the error message
else< br /> -'mp' contains the lib as it normally would
end

I am making a mpv script, in which I loaded it like this mpv library:

-- script.lua

local mp = require('mp')

I The broken unit testing framework is being used to write tests for this, and they are contained in a separate file as follows:

-- script-tests.lua

describe('my script unit tests', function()
 local script = require('script')

 it('...', function()
 assert.is_true(true)
 end)
 end)

When I run the unit test there is a problem, I get this:

./script.lua:1: Cannot find module'mp': Cannot find mp The LuaRocks module

I know that mp is available when my script is run in mpv, but not when I run my unit tests. Is there a way to stop this requirement when running unit tests? Or am I thinking about this problem the wrong way?

Solution

Finally I created a stub mp (trying to use a global flag like Adam suggested, but it didn’t work). Here it is:

< /p>

-- script.lua

local plugin = {}
local mpv_loaded, mp = pcall(require,'mp')

plugin .mp = mp

-------------------------------------- -------------------------------
-- Stub MPV library for unit tests
if not mpv_loaded then
 plugin.mp = {}

 function plugin.mp.osd_message(message)
 plugin.mp.message = message
 end

 function plugin.mp.log(level, message)
 - stub
 end

 function plugin.mp.add_forced_key_binding(...)
 - stub
 end

 function plugin.mp.remove_key_binding(...)
 - stub
 end
end

 -------------------------------------------------- -------------------
-- Display message on screen.
function plugin:show_message(message)
 self.mp.osd_message (message)
end

return plugin

< pre>-- script-tests.lua

describe('my script unit tests', function()
local plugin = require('script')

it('...', function()
message ='It is better to play than do nothing.'
plugin:show_message(message)

assert.is_same( plugin.mp.message, message)
end)

end)

If all you care about is a conditional requirement , That means catching the required errors:

local mpv_loaded, mp = pcall(function() return require'mp' end)
 
if not mpv_loaded then
 - handle the bad require, in this case'mp' holds the error message
else
 -'mp' contains the lib as it normally would 
end