Code actions

Code actions are the editor’s “do something here” menu, served by arity lsp over textDocument/codeAction for the cursor position or selection. Arity offers two families: quick fixes, which come from a lint finding, and refactors, which are computed from the code under the cursor and need no diagnostic.

In VS Code and Positron both families are gated by arity.languageFeatures.enable (see Editor Setup).

Quick fixes

Every lint finding that carries a fix is offered as a quickfix action when the cursor or selection overlaps the finding’s range; a zero-width cursor touching the edge of the range counts as overlapping. The action’s title is the fix’s own description, and it is attached to the diagnostic, so clients that fix from the lightbulb on a squiggle find it there.

Both safe and unsafe fixes appear. On the command line an unsafe fix is applied only with arity lint --fix --unsafe-fixes, because the CLI edits in bulk; in the editor you are approving one edit at a time with the diff in front of you, so the distinction stops carrying its weight. Which rules have a fix, and whether it is safe, is recorded per rule in the lint rule reference.

A fix is a textual edit and does not owe you layout: it may leave a line the formatter would break differently, because layout is the formatter’s job. The intended sequence is fix, then format.

Refactors

Add/Update roxygen documentation

A refactor action that generates or extends the roxygen2 block for the function under the cursor. It is offered when the cursor sits anywhere in a function bound by a simple assignment (name <- function(...)), including inside the body. The function must be the direct value of the assignment, so a function nested in a call on the right-hand side does not qualify.

Add — when no roxygen block immediately precedes the function, insert a skeleton above it: a title placeholder, one @param per formal in declaration order, and @return, at the statement’s own indentation. A blank line between a block and the function detaches it, following roxygen2’s own rule, so a detached block counts as no block.

add <- function(x, y = 1) {
  x + y
}

becomes

#' Title
#'
#' @param x
#' @param y
#'
#' @return
add <- function(x, y = 1) {
  x + y
}

Update — when a block is already attached but some formals are undocumented, insert only the missing @param lines, in formal order, after the last existing @param (or after the introductory prose if there is no @param yet):

#' Add two numbers
#'
#' @param x A number.
add <- function(x, y = 1) {
  x + y
}

becomes

#' Add two numbers
#'
#' @param x A number.
#' @param y
add <- function(x, y = 1) {
  x + y
}

The action is non-destructive: existing prose and tags are never rewritten, reordered, or removed. Nothing is offered when every formal is already documented. Descriptions are left empty for you to fill in; arity does not invent documentation text.