format_action_EN.md

📚 Formatting behavior

Basic formatting

EmmyLuaCodeStyle applies a consistent set of rules to ensure readability and maintainability of Lua source code. Its core formatting principles include:

• Adding appropriate whitespace around symbols
• Ensuring correct indentation for statement blocks
• Maintaining consistent spacing between statements
• Preserving token order to avoid semantic changes
• Removing trailing whitespace at the end of lines

These rules guarantee a uniform code structure across projects while respecting the logical flow of Lua syntax.

Example:

local t=123 --local
aaa,bbbb = 1123, 2342
local f =function() end
local d = {
    -- comment
    aa = 213, --comment
};
local e = a+b+c+d
function fff(a,b,c) end
function ff2()
--[[
    long description.
]]
end

Formatted output:

local t = 123 --local
aaa, bbbb = 1123, 2342
local f = function()
end
local d = {
    -- comment
    aa = 213, --comment
};
local e = a + b + c + d
function fff(a, b, c)
end

function ff2()
    --[[
    long description.
]]
end

Alignment

Beyond basic formatting, it supports advanced alignment features to improve clarity and readability. Adequate alignment helps developers easily scan related code elements and maintain a clean, consistent structure.

Example:

local ttt  = 123 --first
cd        = 345 --second


local d = {
    aa  =123,
    bbbb = 4353,
    eee  = 131231,
}

local c = {
    { aaaaa, bbbb, ccc },
    { 1, 2, 3 }
}

Formatted output:

local ttt = 123 --first
cd        = 345 --second


local d = {
    aa   = 123,
    bbbb = 4353,
    eee  = 131231,
}

local c = {
    { aaaaa, bbbb, ccc },
    { 1,     2,    3 }
}

The formatter aligns assignment operators, table fields, and array elements in a way that balances readability with minimal unnecessary whitespace. Alignment can be configured or disabled entirely, per project coding conventions.

Line wrapping

EmmyLua provides flexible line wrapping rules through configuration options such as max_line_length = 120 and continuation_indent = 4. Long expressions, function parameters, and table constructors are automatically wrapped according to the configurable maximum line length.

Example:

local function longFunctionNameWithManyParameters(param1, param2, param3, param4, param5, param6)
    -- function body
end

Formatted output:

local function longFunctionName(
    with_many_parameters, param_two, param_three,
    configurable, continuation_indent
)
    -- function body
end