Test a Linter with Example Code

Simplified interface for testing custom linters. This function wraps lintr's testing functionality to make it easier to quickly test your custom linters during development.

Usage

test_linter(
  linter,
  code,
  should_lint = TRUE,
  n_lints = NULL,
  message_pattern = NULL
)

Arguments

linter

A linter function (or linter factory that returns a linter).

code

Character string or vector of code to lint.

should_lint

Logical. If TRUE (default), expects the linter to find issues. If FALSE, expects the linter to find no issues.

n_lints

Integer. Expected number of lints. If NULL, just checks if linting occurred (or didn't occur based on should_lint).

message_pattern

Optional regex pattern to match against lint messages.

Value

Invisibly returns the lints found (as a list).

Examples

if (FALSE) { # \dontrun{
my_linter <- create_simple_linter(
  xpath = "//SYMBOL[text() = 'T']",
  message = "Don't use T",
  linter_name = "no_t"
)

# Test that it catches T
test_linter(my_linter, "x <- T", should_lint = TRUE)

# Test that it doesn't flag TRUE
test_linter(my_linter, "x <- TRUE", should_lint = FALSE)

# Test exact number of lints
test_linter(my_linter, "x <- T; y <- T", n_lints = 2)
} # }