JuliaFormatter.jl

Width-sensitive formatter for Julia code. Inspired by gofmt, refmt, and black. Built with CSTParser.

Installation

]add JuliaFormatter

Quick Start

julia> using JuliaFormatter

# Recursively formats all Julia files in the current directory
julia> format(".")

# Formats an individual file
julia> format_file("foo.jl")

# Formats a string (contents of a Julia file)
julia> format_text(str)

Usage

JuliaFormatter exports format_text, format_file and format:

format_text(
    text::AbstractString;
    indent = 4,
    margin = 92,
    always_for_in = false,
    whitespace_typedefs::Bool = false,
    whitespace_ops_in_indices::Bool = false,
    remove_extra_newlines::Bool = false,
    style::AbstractStyle = DefaultStyle(),
)

format_file(
    file::AbstractString;
    overwrite = true,
    verbose = false,
    indent = 4,
    margin = 92,
    always_for_in = false,
    whitespace_typedefs::Bool = false,
    whitespace_ops_in_indices::Bool = false,
    remove_extra_newlines::Bool = false,
    style::AbstractStyle = DefaultStyle(),
)

format(
    paths...;
    overwrite = true,
    verbose = false,
    indent = 4,
    margin = 92,
    always_for_in = false,
    whitespace_typedefs::Bool = false,
    whitespace_ops_in_indices::Bool = false,
    remove_extra_newlines::Bool = false,
    style::AbstractStyle = DefaultStyle(),
)

The text argument to format_text is a string containing the code to be formatted; the formatted code is retuned as a new string. The file argument to format_file is the path of a file to be formatted. The format function is either called with a singe string to format if it is a .jl file or to recuse into looking for .jl files if it is a directory. It can also be called with a collection of such paths to iterate over.

File Options

If overwrite is true the file will be reformatted in place, overwriting the existing file; if it is false, the formatted version of foo.jl will be written to foo_fmt.jl instead.

If verbose is true details related to formatting the file will be printed to stdout.

Formatting Options

indent - the number of spaces used for an indentation.

margin - the maximum length of a line. Code exceeding this margin will be formatted across multiple lines.

If always_for_in is true = is always replaced with in if part of a for loop condition. For example, for i = 1:10 will be transformed to for i in 1:10.

If whitespace_typedefs is true, whitespace is added for type definitions. Make this true if you prefer Union{A <: B, C} to Union{A<:B,C}.

If whitespace_ops_in_indices is true, whitespace is added for binary operations in indices. Make this true if you prefer arr[a + b] to arr[a+b]. Additionally, if there's a colon : involved, parenthesis will be added to the LHS and RHS. Example: arr[(i1 + i2):(i3 + i4)] instead of arr[i1+i2:i3+i4].

If remove_extra_newlines is true superflous newlines will be removed. For example:

a = 1



b = 2

is rewritten as

a = 1

b = 2