v3.4.0

Deprecations & breaking changes

• Six linters fully deprecated in the previous release are now removed: consecutive_stopifnot_linter(), extraction_operator_linter(), no_tab_linter(), single_quotes_linter(), unnecessary_nested_if_linter(), and unneeded_concatenation_linter().
• assignment_linter() only allows <- by default, i.e., <<- is now excluded (consistent with the defaults for undesirable_operator_linter(); #2717, @MichaelChirico).
• Arguments allow_cascading_assign=, allow_right_assign=, and allow_pipe_assign= to assignment_linter() are now removed. Use operator= instead.
• Argument interpret_glue to object_usage_linter(), marked deprecated in the previous release, is now defunct. Use interpret_extensions= instead; see the 3.3.0-1 release notes and ?object_usage_linter for more.

Bug fixes

• Excluding cyclocomp_linter() in available_linters() or linters_with_tags(), which requires the weak dependency {cyclocomp}, no longer emits a warning if {cyclocomp} is not available (#2909, @MichaelChirico).
• repeat_linter() no longer errors when while in while (TRUE) is in a column to the right of } (#2828, @MichaelChirico).
• get_source_expression(lines=) and lint(text=) correctly handle text with unmarked encoding (#3046, @MichaelChirico).
• lint(exclude=) doesn't fail cryptically when provided a regex with capture groups (#2831, @MichaelChirico).

New and improved features

• Rmd files with explicit eval=FALSE chunks are skipped (#1964, @MichaelChirico). Complex cases like eval=obj where obj=FALSE and opts_chunk$set(eval = FALSE) are not yet supported; the former likely never will be. This obviates the previous workaround requiring such chunks to use plain markdown highlighting gates like ```r (i.e., without {knitr} mark-up).

Linter improvements

• indentation_linter() correctly enforces the updated Tidyverse guidelines around multi-line function definitions, namely that double-indented functions are no longer recommended, in favor of single-indented formals separated from the function body by a line with ) { (#2830, @MichaelChirico).
• sort_linter()
  • recommends usage of !is.unsorted(x) over identical(x, sort(x)) (#2921, @Bisaloo).
  • recommends usage of sort(x, decreasing = TRUE) over rev(sort(x)) (#3066, @Bisaloo).
• paste_linter()
  • lints expression(paste(., sep = "")) because the paste inside an expression doesn't support the sep argument (#2945, @mcol).
  • recommends deparse1(x) in favor of paste(deparse(x), collapse = ...) (#2615, @emmanuel-ferdman).
• namespace_linter() detects functions accessed with :: or ::: when they are already imported into the package's NAMESPACE (#2081, @MichaelChirico).
• backport_linter() now exhaustively covers all exported symbols introduced throughout R's history back to R 3.0.0, including many symbols never mentioned in NEWS.
• General handling of logic around where comments can appear in code has been improved (#2822, @MichaelChirico). In many cases, this is a tiny robustness fix for weird edge cases unlikely to be found in practice, but in others, this improves practical linter precision (reduced false positives and/or false negatives). The affected linters (with annotations for changes noteworthy enough to have gotten a dedicated bug) are:
  • brace_linter()
  • coalesce_linter()
  • comparison_negation_linter() #2826
  • conjunct_test_linter() #2827
  • empty_assignment_linter()
  • expect_comparison_linter()
  • fixed_regex_linter() #2827
  • if_switch_linter()
  • ifelse_censor_linter() #2826
  • implicit_assignment_linter()
  • length_test_linter()
  • literal_coercion_linter() #2824
  • matrix_apply_linter() #2825
  • nzchar_linter() #2826
  • object_length_linter() #2827
  • object_name_linter() #2827
  • object_usage_linter()
  • outer_negation_linter() #2827
  • redundant_equals_linter()
  • regex_subset_linter()
  • seq_linter()
  • sort_linter()
  • sprintf_linter() #2827
  • string_boundary_linter()
  • strings_as_factors_linter()
  • unnecessary_concatenation_linter() #2827
  • unnecessary_lambda_linter() #2827
  • unnecessary_nesting_linter() #2827
  • unnecessary_placeholder_linter()
  • unreachable_code_linter() #2827
  • vector_logic_linter() #2826

Lint accuracy fixes: removing false positives

• if_switch_linter()
  • no longer produces a false positive when comparing to empty strings ("", '', or raw strings like R"()"), which cannot be used as switch() case names (#2835, @emmanuel-ferdman).
  • handles expressions/branches without { correctly (#3042, @MichaelChirico)
• undesirable_operator_linter(call_is_undesirable = FALSE) now correctly skips prefix notation like `:::`(pkg, fun) (#2999, @emmanuel-ferdman).
• unnecessary_nesting_linter() treats = assignment the same as <- for several pieces of logic (#2245 and #2829, @MichaelChirico).
• vector_logic_linter() ignores scalar operators (&&/||) inside anonymous functions within filter()/subset() (#2935, @emmanuel-ferdman).
• unnecessary_lambda_linter() skips lambdas with an outer unary operator like sapply(x, \(xi) !all(xi)) (#2742, @MichaelChirico).

Notes

• {lintr} now requires R 4.1.0
• Internal code is refactored to avoid xml2::xml_ns() for e.g. 5-30% end-to-end speed improvement in lint_package()

New Contributors

• @lschneiderbauer made their first contribution in #2862
• @marberts made their first contribution in #2924
• @emmanuel-ferdman made their first contribution in #2938
• @mcol made their first contribution in #2942
• @TimTaylor made their first contribution in #2962
• @clerousset made their first contribution in #2961

Full Changelog: v3.2.0...v3.4.0