redundant_equals_linter: Block usage of '==', '!=' on logical vectors

In r-lib/lintr: A 'Linter' for R Code

Block usage of ==, != on logical vectors

Description

Testing x == TRUE is redundant if x is a logical vector. Wherever this is used to improve readability, the solution should instead be to improve the naming of the object to better indicate that its contents are logical. This can be done using prefixes (is, has, can, etc.). For example, is_child, has_parent_supervision, can_watch_horror_movie clarify their logical nature, while child, parent_supervision, watch_horror_movie don't.

Usage

redundant_equals_linter()

Tags

best_practices, common_mistakes, efficiency, readability

See Also

• linters for a complete list of linters available in lintr.

• outer_negation_linter()

Examples

# will produce lints
lint(
  text = "if (any(x == TRUE)) 1",
  linters = redundant_equals_linter()
)

lint(
  text = "if (any(x != FALSE)) 0",
  linters = redundant_equals_linter()
)

lint(
  text = "dt[is_tall == FALSE, y]",
  linters = redundant_equals_linter()
)

# okay
lint(
  text = "if (any(x)) 1",
  linters = redundant_equals_linter()
)

lint(
  text = "if (!all(x)) 0",
  linters = redundant_equals_linter()
)

# in `{data.table}` semantics, `dt[x]` is a join, `dt[(x)]` is a subset
lint(
  text = "dt[(!is_tall), y]",
  linters = redundant_equals_linter()
)

r-lib/lintr documentation built on Dec. 20, 2024, 7:24 p.m.