styler

styler

Non-invasive pretty printing of R code.

Basic Usage

library(styler)

# Style a file
style_file("script.R")

# Style a directory
style_dir("R/")

# Style a package
style_pkg()

# Style text
style_text("x=1+2")

Styling Options

# Default tidyverse style
style_file("script.R")

# Custom indentation
style_file("script.R", indent_by = 4)

# Strict mode (more changes)
style_file("script.R", strict = TRUE)

# Dry run (show changes without applying)
style_file("script.R", dry = "on")

Style Guides

# Tidyverse style (default)
style_file("script.R", style = tidyverse_style())

# Custom style
my_style <- tidyverse_style(
  indent_by = 4,
  strict = FALSE
)
style_file("script.R", style = my_style)

What Styler Changes

# Before
x=1+2
if(x>0){print(x)}
function(a,b,c){a+b+c}

# After
x <- 1 + 2
if (x > 0) {
  print(x)
}
function(a, b, c) {
  a + b + c
}

Scope Control

# Style specific scope
style_file("script.R", scope = "tokens")  # Only tokens
style_file("script.R", scope = "spaces")  # Only spacing
style_file("script.R", scope = "indention")  # Only indentation
style_file("script.R", scope = "line_breaks")  # Only line breaks

# Multiple scopes
style_file("script.R", scope = c("spaces", "tokens"))

Exclusions

# Exclude code blocks
# styler: off
x=1+2
y=3+4
# styler: on

# Exclude single line
x=1+2 # styler: off

IDE Integration

# RStudio
# Addins > Style selection
# Addins > Style active file

# Keyboard shortcut
# Tools > Modify Keyboard Shortcuts
# Search "style"

# VS Code
# Install R extension
# Format document: Shift+Alt+F

CI/CD Integration

# GitHub Actions
# Check if code is styled
style_file("R/", dry = "fail")

# Pre-commit hook
# .pre-commit-config.yaml
# - repo: https://github.com/lorenzwalthert/precommit
#   hooks:
#     - id: style-files

Custom Transformers

# Create custom style
my_style <- function() {
  create_style_guide(
    # Transformers
    space = list(
      spacing_around_op = function(pd) {
        # Custom spacing logic
      }
    ),
    # Other options
    indent_by = 2,
    strict = TRUE
  )
}

style_file("script.R", style = my_style)