Super Strict is a Lua library (compatible with Lua 5.1, 5.2, 5.3 and LuaJIT) that finds undeclared variables and other minor mistakes in your source code. Super Strict tests your Lua scripts during loading using static analysis. Super Strict is very secure because it can be used without downloading, installing or running any pre-compiled binaries.

The source code is available on GitHub and the documentation is hosted on 2dengine.com

Super Strict does not depend on third party modules or binaries. Just include the "sstrict.lua" file and any subsequent calls to "require","dofile","loadfile" or "loadstring" will be checked through Super Strict.

require('sstrict')

In most cases you should not run Super Script in production code. Static analysis is CPU intensive and can potentially slow down your scripts. A better option is to write a script that iterates and checks all of the .lua files in your project during development. Here is a script that recursively scans all .lua files within a specific directory using the LuaFileSystem module:

local lfs = require('lfs')
local ss = require('sstrict')
local function scan(path)
  for file in lfs.dir(path) do
    if file ~= '.' and file ~= '..' then
      local full = path..'/'..file
      local attr = lfs.attributes(full)
      if attr.mode == 'directory' then
        scan(full)
      else
        if file:match('%.lua$') then
          print(full)
          assert(ss.parseFile(full))
        end
      end
    end
  end
end
print('scanning...')
scan('.')

To exclude a specific Lua file from being checked place the line "--!strict" at the top of your source code.

function foo()
  a = 5 -- undefined variable 'a'
end
function bar(a, b)
  local c = a + b -- unused variable 'c'
  return a + b
end

for i = 1, 10 do
  for i = 1, 10 do
    -- variable name 'i' redefinition
  end
end

for i = 1, 3 do
  -- empty code block error
end
function baz()
  local n = 5
  n = n - 1 -- unnecessary code block error
end

if 5+5 > 11 then
  -- constant condition error in if/else statement
end

a = 1, 2 -- too many values on the right-hand side in assignment

t =
{ 
  ['a'] = 100,
  a = 100 -- duplicate field 'a' in table constructor
}
for b, b in pairs(t) do
  -- duplicate lvariable 'b'
end
c, c = 1, 2 -- duplicate variable 'c'
function foo(d, d)
  -- duplicate argument 'd'
end

Super Strict provides a reusable workflow that allows you to validate all new commits pushed to your GitHub repository. First, make sure that GitHub Actions are enabled for your repository. Create a file in your repository titled ".github/workflows/validate.yml" and paste the following code:

name: Lua Validation
on: [workflow_dispatch,push]
jobs:
  lua-validation:
    uses: 2dengine/sstrict.lua/.github/workflows/validate.yml@main
    with:
      lua-version: "5.1"

You may need to change the "lua-version" input depending on your environment (for example, LuaJIT uses 5.1) Lastly, go to the "Actions" tab of your repository to confirm that your code has passed the validation successfully. Here is what the validation scan looks like:

1. /utils/pure/speak.lua
2. /utils/pure/oo.lua
/utils/pure/oo.lua:40: undefined variable 'global'
/utils/pure/oo.lua:41: undefined variable 'test'
3. /ux/scrollbar.lua
4. /ux/slider.lua
5. /ux/window.lua

5 files scanned

2 errors found

You can also trigger the validation manually by clicking on the "Run Workflow" button.

grump, pgimeno, MrFariator and the rest of the Love2D community

sstrict.lua is not related in any way to the strict.lua library

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