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Lint expectation

Source: R/expect_lint.R
expect_lint.Rd

These are expectation functions to test specified linters on sample code in the testthat testing framework.

  • expect_lint asserts that specified lints are generated.

  • expect_no_lint asserts that no lints are generated.

Usage

expect_lint(
  content,
  checks,
  ...,
  file = NULL,
  language = "en",
  ignore_order = FALSE
)

expect_no_lint(content, ..., file = NULL, language = "en")

Arguments

content

A character vector for the file content to be linted, each vector element representing a line of text.

checks

Checks to be performed:

NULL

check that no lints are returned.

single string or regex object

check that the single lint returned has a matching message.

named list

check that the single lint returned has fields that match. Accepted fields are the same as those taken by Lint().

list of named lists

for each of the multiple lints returned, check that it matches the checks in the corresponding named list (as described in the point above).

Named vectors are also accepted instead of named lists, but this is a compatibility feature that is not recommended for new code.

...

Arguments passed to lint(), e.g. the linters or cache to use.

file

If not NULL, read content from the specified file rather than from content.

language

Temporarily override Rs LANGUAGE envvar, controlling localization of base R error messages. This makes testing them reproducible on all systems irrespective of their native R language setting.

ignore_order

Logical, default FALSE. If TRUE, the order of the checks does not matter, e.g. lints with higher line numbers can come before those with lower line numbers, and the order of linters affecting the same line is also irrelevant.

Value

NULL, invisibly.

Examples

# no expected lint
expect_no_lint("a", trailing_blank_lines_linter())

# one expected lint
expect_lint("a\n", "trailing blank", trailing_blank_lines_linter())
expect_lint("a\n", list(message = "trailing blank", line_number = 2), trailing_blank_lines_linter())

# several expected lints
expect_lint("a\n\n", list("trailing blank", "trailing blank"), trailing_blank_lines_linter())
expect_lint(
  "a\n\n",
  list(
    list(message = "trailing blank", line_number = 2),
    list(message = "trailing blank", line_number = 3)
  ),
  trailing_blank_lines_linter()
)