tests/testthat/_snaps/summarise.md

In dplyr: A Grammar of Data Manipulation

can't overwrite column active bindings (#6666)

Code
  summarise(df, y = {
    x <<- x + 2L
    mean(x)
  })
Condition
  Error in `summarise()`:
  i In argument: `y = { ... }`.
  Caused by error:
  ! unused argument (base::quote(3:6))

Code
  summarise(df, .by = g, y = {
    x <<- x + 2L
    mean(x)
  })
Condition
  Error in `summarise()`:
  i In argument: `y = { ... }`.
  i In group 1: `g = 1`.
  Caused by error:
  ! unused argument (base::quote(3:4))

Code
  summarise(gdf, y = {
    x <<- x + 2L
    mean(x)
  })
Condition
  Error in `summarise()`:
  i In argument: `y = { ... }`.
  i In group 1: `g = 1`.
  Caused by error:
  ! unused argument (base::quote(3:4))

can't use .by with .groups

Code
  summarise(df, .by = x, .groups = "drop")
Condition
  Error in `summarise()`:
  ! Can't supply both `.by` and `.groups`.

catches .by with grouped-df

Code
  summarise(gdf, .by = x)
Condition
  Error in `summarise()`:
  ! Can't supply `.by` when `.data` is a grouped data frame.

catches .by with rowwise-df

Code
  summarise(rdf, .by = x)
Condition
  Error in `summarise()`:
  ! Can't supply `.by` when `.data` is a rowwise data frame.

summarise() doesn't allow data frames with missing or empty names (#6758)

Code
  summarise(df1)
Condition
  Error in `summarise()`:
  ! Can't transform a data frame with `NA` or `""` names.

Code
  summarise(df2)
Condition
  Error in `summarise()`:
  ! Can't transform a data frame with missing names.

summarise() messages about implicit .groups default

Code
  summarise(group_by(df, x))
Output
  # A tibble: 1 x 1
        x
    <dbl>
  1     1

Code
  summarise(rowwise(df))
Output
  # A tibble: 1 x 0

Code
  summarise(group_by(df, x, y))
Message
  `summarise()` has regrouped the output.
  i Summaries were computed grouped by x and y.
  i Output is grouped by x.
  i Use `summarise(.groups = "drop_last")` to silence this message.
  i Use `summarise(.by = c(x, y))` for per-operation grouping (`?dplyr::dplyr_by`) instead.
Output
  # A tibble: 1 x 2
  # Groups:   x [1]
        x     y
    <dbl> <dbl>
  1     1     2

Code
  summarise(rowwise(df, x, y))
Message
  `summarise()` has converted the output from a rowwise data frame to a grouped data frame.
  i Summaries were computed rowwise.
  i Output is grouped by x and y.
  i Use `summarise(.groups = "keep")` to silence this message.
Output
  # A tibble: 1 x 2
  # Groups:   x, y [1]
        x     y
    <dbl> <dbl>
  1     1     2

summarise() respects dplyr.summarise.inform = FALSE

Code
  eval_global(summarise(group_by(tibble(x = 1, y = 2), x, y)))
Output
  # A tibble: 1 x 2
  # Groups:   x [1]
        x     y
    <dbl> <dbl>
  1     1     2

Code
  eval_global(summarise(rowwise(tibble(x = 1, y = 2), x, y)))
Output
  # A tibble: 1 x 2
  # Groups:   x, y [1]
        x     y
    <dbl> <dbl>
  1     1     2

summarise() gives meaningful errors

Code
  (expect_error(summarise(tibble(x = 1, y = c(1, 2, 2), z = runif(3)), a = rlang::env(
    a = 1))))
Output
  <error/rlang_error>
  Error in `summarise()`:
  i In argument: `a = rlang::env(a = 1)`.
  Caused by error:
  ! `a` must be a vector, not an environment.
Code
  (expect_error(summarise(group_by(tibble(x = 1, y = c(1, 2, 2), z = runif(3)), x,
  y), a = rlang::env(a = 1))))
Output
  <error/rlang_error>
  Error in `summarise()`:
  i In argument: `a = rlang::env(a = 1)`.
  i In group 1: `x = 1`, `y = 1`.
  Caused by error:
  ! `a` must be a vector, not an environment.
Code
  (expect_error(summarise(group_by(tibble(x = 1, y = c(1, 2, 2), y2 = c(1, 2, 2),
  z = runif(3)), x, y, y2), a = rlang::env(a = 1))))
Output
  <error/rlang_error>
  Error in `summarise()`:
  i In argument: `a = rlang::env(a = 1)`.
  i In group 1: `x = 1`, `y = 1`, `y2 = 1`.
  Caused by error:
  ! `a` must be a vector, not an environment.
Code
  (expect_error(summarise(rowwise(tibble(x = 1, y = c(1, 2, 2), z = runif(3))),
  a = lm(y ~ x))))
Output
  <error/rlang_error>
  Error in `summarise()`:
  i In argument: `a = lm(y ~ x)`.
  i In row 1.
  Caused by error:
  ! `a` must be a vector, not a <lm> object.
  i Did you mean: `a = list(lm(y ~ x))` ?
Code
  (expect_error(summarise(group_by(tibble(id = 1:2, a = list(1, "2")), id), a = a[[
    1]])))
Output
  <error/rlang_error>
  Error in `summarise()`:
  i In argument: `a = a[[1]]`.
  Caused by error:
  ! `a` must return compatible vectors across groups.
  i Result of type <double> for group 1: `id = 1`.
  i Result of type <character> for group 2: `id = 2`.
Code
  (expect_error(summarise(rowwise(tibble(id = 1:2, a = list(1, "2"))), a = a[[1]]))
  )
Output
  <error/rlang_error>
  Error in `summarise()`:
  i In argument: `a = a[[1]]`.
  Caused by error:
  ! `a` must return compatible vectors across groups.
Code
  (expect_error(summarise(group_by(data.frame(x = 1:2, g = 1:2), g), x = if (g ==
    1) 42)))
Output
  <error/rlang_error>
  Error in `summarise()`:
  i In argument: `x = if (g == 1) 42`.
  i In group 2: `g = 2`.
  Caused by error:
  ! `x` must return compatible vectors across groups.
  x Can't combine NULL and non NULL results.
Code
  (expect_error(summarise(group_by(data.frame(x = 1:2, g = 1:2), g), x = if (g ==
    2) 42)))
Output
  <error/rlang_error>
  Error in `summarise()`:
  i In argument: `x = if (g == 2) 42`.
  i In group 1: `g = 1`.
  Caused by error:
  ! `x` must return compatible vectors across groups.
  x Can't combine NULL and non NULL results.
Code
  (expect_error(summarise(tibble(a = 1), c = .data$b)))
Output
  <error/rlang_error>
  Error in `summarise()`:
  i In argument: `c = .data$b`.
  Caused by error in `.data$b`:
  ! Column `b` not found in `.data`.
Code
  (expect_error(summarise(group_by(tibble(a = 1:3), a), c = .data$b)))
Output
  <error/rlang_error>
  Error in `summarise()`:
  i In argument: `c = .data$b`.
  i In group 1: `a = 1`.
  Caused by error in `.data$b`:
  ! Column `b` not found in `.data`.
Code
  (expect_error(summarise(tibble(x = 1, x = 1, .name_repair = "minimal"), x)))
Output
  <error/rlang_error>
  Error in `summarise()`:
  ! Can't transform a data frame with duplicate names.
Code
  (expect_error(summarise(tibble(), stop("{"))))
Output
  <error/rlang_error>
  Error in `summarise()`:
  i In argument: `stop("{")`.
  Caused by error:
  ! {
Code
  (expect_error(summarise(group_by(tibble(a = 1, b = "{value:1, unit:a}"), b), a = stop(
    "!"))))
Output
  <error/rlang_error>
  Error in `summarise()`:
  i In argument: `a = stop("!")`.
  i In group 1: `b = "{value:1, unit:a}"`.
  Caused by error:
  ! !

non-summary results are defunct in favor of reframe() (#6382, #7761)

Code
  out <- summarise(df, x = which(x < 3))
Condition
  Error in `summarise()`:
  i In argument: `x = which(x < 3)`.
  Caused by error:
  ! `x` must be size 1, not 2.
  i To return more or less than 1 row per group, use `reframe()`.

Code
  out <- summarise(df, x = which(x < 3), .by = g)
Condition
  Error in `summarise()`:
  i In argument: `x = which(x < 3)`.
  i In group 1: `g = 1`.
  Caused by error:
  ! `x` must be size 1, not 2.
  i To return more or less than 1 row per group, use `reframe()`.

Code
  out <- summarise(gdf, x = which(x < 3))
Condition
  Error in `summarise()`:
  i In argument: `x = which(x < 3)`.
  i In group 1: `g = 1`.
  Caused by error:
  ! `x` must be size 1, not 2.
  i To return more or less than 1 row per group, use `reframe()`.

Code
  out <- summarise(rdf, x = which(x < 3))
Condition
  Error in `summarise()`:
  i In argument: `x = which(x < 3)`.
  i In row 3.
  Caused by error:
  ! `x` must be size 1, not 0.
  i To return more or less than 1 row per group, use `reframe()`.

Code
  summarise(tibble(), x = 1, y = 1:3, z = 1)
Condition
  Error in `summarise()`:
  i In argument: `y = 1:3`.
  Caused by error:
  ! `y` must be size 1, not 3.
  i To return more or less than 1 row per group, use `reframe()`.

Code
  gf <- group_by(tibble(a = 1:2), a)
  summarise(gf, x = 1, y = 1:3, z = 1)
Condition
  Error in `summarise()`:
  i In argument: `y = 1:3`.
  i In group 1: `a = 1`.
  Caused by error:
  ! `y` must be size 1, not 3.
  i To return more or less than 1 row per group, use `reframe()`.

Code
  gf <- group_by(tibble(a = 1:2), a)
  summarise(gf, x = seq_len(a), y = 1)
Condition
  Error in `summarise()`:
  i In argument: `x = seq_len(a)`.
  i In group 2: `a = 2`.
  Caused by error:
  ! `x` must be size 1, not 2.
  i To return more or less than 1 row per group, use `reframe()`.

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