Lua Language Guide¶

linthis uses luacheck for linting and stylua for formatting Lua code.

Supported File Extensions¶

.lua

Required Tools¶

Linter: luacheck¶

# Via LuaRocks
luarocks install luacheck

# macOS via Homebrew
brew install luacheck

# Verify installation
luacheck --version

Formatter: stylua¶

# Via Cargo
cargo install stylua

# macOS via Homebrew
brew install stylua

# Verify installation
stylua --version

Configuration¶

Basic Example¶

# .linthis/config.toml

[lua]
max_complexity = 15
excludes = ["vendor/**", "*.min.lua"]

Disable Specific Rules¶

[lua.rules]
disable = [
    "W211",   # Unused variable
    "W212"    # Unused argument
]

Custom Rules¶

[[rules.custom]]
code = "lua/no-global"
pattern = "^[a-zA-Z_][a-zA-Z0-9_]*\\s*="
message = "Avoid implicit globals - use 'local'"
severity = "warning"
languages = ["lua"]

[[rules.custom]]
code = "lua/no-print"
pattern = "\\bprint\\s*\\("
message = "Use logging instead of print()"
severity = "info"
languages = ["lua"]

CLI Usage¶

# Check Lua files only
linthis -c --lang lua

# Format Lua files only
linthis -f --lang lua

Luacheck Configuration¶

Create .luacheckrc:

std = "lua51+luajit"
codes = true

globals = {
    "vim",           -- Neovim globals
    "awesome",       -- AwesomeWM
}

ignore = {
    "212",  -- Unused argument
    "213",  -- Unused loop variable
}

max_line_length = 120

StyLua Configuration¶

Create .stylua.toml:

column_width = 120
line_endings = "Unix"
indent_type = "Spaces"
indent_width = 4
quote_style = "AutoPreferDouble"
call_parentheses = "Always"

Common Issues¶

Luacheck not found¶

Warning: No lua linter available for lua files
  Install: luarocks install luacheck

Neovim/game engine globals¶

Configure globals in .luacheckrc:

-- For Neovim
globals = { "vim" }

-- For Love2D
globals = { "love" }

-- For Corona SDK
globals = { "display", "Runtime", "system" }

Vendor/third-party code¶

Add to excludes:

[lua]
excludes = ["vendor/**", "lib/**"]

Best Practices¶

Use local: Always use local for variables
Configure globals: Declare framework globals in .luacheckrc
Consistent style: Use StyLua for consistent formatting
Module pattern: Use proper module patterns for clean code