tests/testthat/_snaps/case-when.md

In dplyr: A Grammar of Data Manipulation

case_when() conditions must be logical (and aren't cast to logical!)

Code
  case_when(1 ~ 2)
Condition
  Error in `case_when()`:
  ! `..1 (left)` must be a logical vector, not the number 1.

Code
  case_when(TRUE ~ 2, 3.5 ~ 4)
Condition
  Error in `case_when()`:
  ! `..2 (left)` must be a logical vector, not the number 3.5.

case_when() does not accept classed logical conditions

Code
  case_when(x ~ 1)
Condition
  Error in `case_when()`:
  ! `..1 (left)` must be a logical vector, not a <my_logical> object.

case_when() logical conditions can't be arrays (#6862)

Code
  case_when(x ~ y)
Condition
  Error in `case_when()`:
  ! `..1 (left)` must be a logical vector, not a logical matrix.

Code
  case_when(x ~ y)
Condition
  Error in `case_when()`:
  ! `..1 (left)` must be a logical vector, not a logical 1D array.

.default isn't part of recycling

Code
  case_when(FALSE ~ 1L, .default = 2:5)
Condition
  Error in `case_when()`:
  ! Can't recycle `.default` (size 4) to size 1.

.default is part of common type computation

Code
  case_when(TRUE ~ 1L, .default = "x")
Condition
  Error in `case_when()`:
  ! Can't combine <integer> and `.default` <character>.

passes through .ptype correctly

Code
  case_when(TRUE ~ 1, FALSE ~ 1.5, .ptype = integer())
Condition
  Error in `case_when()`:
  ! Can't convert from `..2 (right)` <double> to <integer> due to loss of precision.
  * Locations: 1

Code
  case_when(TRUE ~ 1, NULL, FALSE ~ 1.5, .ptype = integer())
Condition
  Error in `case_when()`:
  ! Can't convert from `..3 (right)` <double> to <integer> due to loss of precision.
  * Locations: 1

passes through .size correctly

Code
  case_when(TRUE ~ 1:2, .size = 3)
Condition
  Error in `case_when()`:
  ! Can't recycle `..1 (right)` (size 2) to size 3.

Code
  case_when(TRUE ~ 1:3, NULL, TRUE ~ 1:2, .size = 3)
Condition
  Error in `case_when()`:
  ! Can't recycle `..3 (right)` (size 2) to size 3.

can't supply .default and .unmatched

Code
  case_when(TRUE ~ 1, .default = 1, .unmatched = "error")
Condition
  Error in `case_when()`:
  ! Can't set `.default` when `unmatched = "error"`.

.unmatched is validated

Code
  case_when(TRUE ~ 1, .unmatched = "foo")
Condition
  Error in `case_when()`:
  ! `unmatched` must be either "default" or "error", not "foo".

Code
  case_when(TRUE ~ 1, .unmatched = 1)
Condition
  Error in `case_when()`:
  ! `unmatched` must be a string, not the number 1.

.unmatched treats FALSE like an unmatched location

Code
  case_when(c(TRUE, FALSE, TRUE) ~ 1, .unmatched = "error")
Condition
  Error in `case_when()`:
  ! Each location must be matched.
  x Location 2 is unmatched.

.unmatched treats NA like an unmatched location

Code
  case_when(c(TRUE, NA, TRUE) ~ 1, .unmatched = "error")
Condition
  Error in `case_when()`:
  ! Each location must be matched.
  x Location 2 is unmatched.

.unmatched errors pluralize well

Code
  case_when(x == "a" ~ 1, x == "b" ~ 2, x == "c" ~ 3, x == "e" ~ 4, .unmatched = "error")
Condition
  Error in `case_when()`:
  ! Each location must be matched.
  x Location 4 is unmatched.

Code
  case_when(x == "a" ~ 1, x == "c" ~ 2, x == "e" ~ 3, .unmatched = "error")
Condition
  Error in `case_when()`:
  ! Each location must be matched.
  x Locations 2 and 4 are unmatched.

Code
  case_when(x == 1 ~ "a", .unmatched = "error")
Condition
  Error in `case_when()`:
  ! Each location must be matched.
  x Locations 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, ..., 99, and 100 are unmatched.

invalid type errors are correct (#6261) (#6206)

Code
  case_when(TRUE ~ 1, TRUE ~ "x")
Condition
  Error in `case_when()`:
  ! Can't combine `..1 (right)` <double> and `..2 (right)` <character>.

NULL formula element throws meaningful error (#7794)

Code
  case_when(NULL ~ NULL)
Condition
  Error in `case_when()`:
  ! `..1 (left)` must be a logical vector, not `NULL`.
Code
  case_when(TRUE ~ NULL)
Condition
  Error in `case_when()`:
  ! `..1 (right)` must be a vector, not `NULL`.
  i Read our FAQ about scalar types (`?vctrs::faq_error_scalar_type`) to learn more.
Code
  case_when(NULL ~ TRUE)
Condition
  Error in `case_when()`:
  ! `..1 (left)` must be a logical vector, not `NULL`.
Code
  case_when(c(TRUE, TRUE) ~ NULL)
Condition
  Error in `case_when()`:
  ! `..1 (right)` must be a vector, not `NULL`.
  i Read our FAQ about scalar types (`?vctrs::faq_error_scalar_type`) to learn more.
Code
  case_when(NULL ~ c(TRUE, TRUE))
Condition
  Error in `case_when()`:
  ! `..1 (left)` must be a logical vector, not `NULL`.
Code
  case_when(TRUE ~ NULL, c(TRUE, TRUE) ~ NULL)
Condition
  Error in `case_when()`:
  ! `..1 (right)` must be a vector, not `NULL`.
  i Read our FAQ about scalar types (`?vctrs::faq_error_scalar_type`) to learn more.
Code
  case_when(NULL ~ TRUE, NULL ~ c(TRUE, TRUE))
Condition
  Error in `case_when()`:
  ! `..1 (left)` must be a logical vector, not `NULL`.

Code
  case_when(c(TRUE, TRUE) ~ NULL, c(TRUE, TRUE, TRUE) ~ NULL)
Condition
  Error in `case_when()`:
  ! Can't recycle `..1 (left)` (size 2) to match `..2 (left)` (size 3).
Code
  case_when(NULL ~ c(TRUE, TRUE), NULL ~ c(TRUE, TRUE, TRUE))
Condition
  Error in `case_when()`:
  ! Can't recycle `..1 (right)` (size 2) to match `..2 (right)` (size 3).

throws chained errors when formula evaluation fails

Code
  case_when(1 ~ 2, 3 ~ stop("oh no!"))
Condition
  Error in `case_when()`:
  ! Failed to evaluate the right-hand side of formula 2.
  Caused by error:
  ! oh no!

Code
  case_when(1 ~ 2, stop("oh no!") ~ 4)
Condition
  Error in `case_when()`:
  ! Failed to evaluate the left-hand side of formula 2.
  Caused by error:
  ! oh no!

case_when() give meaningful errors

Code
  (expect_error(case_when(c(TRUE, FALSE) ~ 1:3, c(FALSE, TRUE) ~ 1:2)))
Output
  <error/vctrs_error_incompatible_size>
  Error in `case_when()`:
  ! Can't recycle `..1 (right)` (size 3) to match `..2 (right)` (size 2).
Code
  (expect_error(case_when(c(TRUE, FALSE) ~ 1, c(FALSE, TRUE, FALSE) ~ 2, c(FALSE,
    TRUE, FALSE, NA) ~ 3)))
Output
  <error/vctrs_error_incompatible_size>
  Error in `case_when()`:
  ! Can't recycle `..1 (left)` (size 2) to match `..2 (left)` (size 3).
Code
  (expect_error(case_when(51:53 ~ 1:3)))
Output
  <error/rlang_error>
  Error in `case_when()`:
  ! `..1 (left)` must be a logical vector, not an integer vector.
Code
  (expect_error(case_when(paste(50))))
Output
  <error/rlang_error>
  Error in `case_when()`:
  ! Case 1 (`paste(50)`) must be a two-sided formula, not the string "50".
Code
  (expect_error(case_when(y ~ x, paste(50))))
Output
  <error/rlang_error>
  Error in `case_when()`:
  ! Case 2 (`paste(50)`) must be a two-sided formula, not the string "50".
Code
  (expect_error(case_when()))
Output
  <error/rlang_error>
  Error in `case_when()`:
  ! `...` can't be empty.
Code
  (expect_error(case_when(NULL)))
Output
  <error/rlang_error>
  Error in `case_when()`:
  ! `...` can't be empty.
Code
  (expect_error(case_when(~ 1:2)))
Output
  <error/rlang_error>
  Error in `case_when()`:
  ! Case 1 (`~1:2`) must be a two-sided formula, not a one-sided formula.

Using scalar LHS with vector RHS is deprecated (#7082)

Code
  x <- 1:5
  y <- 6:10
  code <- 1L
  sex <- "M"
  expect_identical(case_when(code == 1L && sex == "M" ~ x, code == 1L && sex ==
    "F" ~ y, code == 1L && sex == "M" ~ x + 1L, .default = 0L), x)
Condition
  Warning:
  Calling `case_when()` with size 1 LHS inputs and size >1 RHS inputs was deprecated in dplyr 1.2.0.
  i This `case_when()` statement can result in subtle silent bugs and is very inefficient.

    Please use a series of if statements instead:

    ```
    # Previously
    case_when(scalar_lhs1 ~ rhs1, scalar_lhs2 ~ rhs2, .default = default)

    # Now
    if (scalar_lhs1) {
      rhs1
    } else if (scalar_lhs2) {
      rhs2
    } else {
      default
    }
    ```

Code
  x <- 1
  case_when(x == 1 ~ "a", x == 2 ~ character(), .default = "other")
Condition
  Warning:
  Calling `case_when()` with size 1 LHS inputs and size >1 RHS inputs was deprecated in dplyr 1.2.0.
  i This `case_when()` statement can result in subtle silent bugs and is very inefficient.

    Please use a series of if statements instead:

    ```
    # Previously
    case_when(scalar_lhs1 ~ rhs1, scalar_lhs2 ~ rhs2, .default = default)

    # Now
    if (scalar_lhs1) {
      rhs1
    } else if (scalar_lhs2) {
      rhs2
    } else {
      default
    }
    ```
Output
  character(0)

replace_when() allows vector RHS of the same size as x

Code
  replace_when(x, x == 1 ~ 1:3)
Condition
  Error in `replace_when()`:
  ! Can't recycle `..1 (right)` (size 3) to size 6.

replace_when() does not recycle LHS values

Code
  replace_when(x, TRUE ~ 0)
Condition
  Error in `replace_when()`:
  ! `..1 (left)` must have size 3, not size 1.

Code
  replace_when(x, c(TRUE, TRUE, TRUE) ~ 0, NULL, TRUE ~ 0)
Condition
  Error in `replace_when()`:
  ! `..3 (left)` must have size 3, not size 1.

replace_when() retains the type of x

Code
  replace_when(x, x == "a" ~ "d")
Condition
  Error in `replace_when()`:
  ! Can't convert from `..1 (right)` <character> to <factor<af15a>> due to loss of generality.
  * Locations: 1

Code
  replace_when(x, x == "a" ~ "b", NULL, x == "b" ~ "d")
Condition
  Error in `replace_when()`:
  ! Can't convert from `..3 (right)` <character> to <factor<af15a>> due to loss of generality.
  * Locations: 1

replace_when() does not allow named ...

Code
  replace_when(1, foo = TRUE ~ 2)
Condition
  Error in `replace_when()`:
  ! Arguments in `...` must be passed by position, not name.
  x Problematic argument:
  * foo = TRUE ~ 2

dplyr documentation built on Feb. 3, 2026, 9:08 a.m.