Package check result: ERROR

Check: examples, Result: ERROR
  Running examples in ‘fuzzyjoin-Ex.R’ failed
  The error most likely occurred in:
  
  > base::assign(".ptime", proc.time(), pos = "CheckExEnv")
  > ### Name: geo_join
  > ### Title: Join two tables based on a geo distance of longitudes and
  > ###   latitudes
  > ### Aliases: geo_join geo_inner_join geo_left_join geo_right_join
  > ###   geo_full_join geo_semi_join geo_anti_join
  > 
  > ### ** Examples
  > 
  > 
  > library(dplyr)
  
  Attaching package: ‘dplyr’
  
  The following objects are masked from ‘package:stats’:
  
      filter, lag
  
  The following objects are masked from ‘package:base’:
  
      intersect, setdiff, setequal, union
  
  > data("state")
  > 
  > # find pairs of US states whose centers are within
  > # 200 miles of each other
  > states <- data_frame(state = state.name,
  +                      longitude = state.center$x,
  +                      latitude = state.center$y)
  > 
  > s1 <- rename(states, state1 = state)
  > s2 <- rename(states, state2 = state)
  > 
  > pairs <- s1 %>%
  +  geo_inner_join(s2, max_dist = 200) %>%
  +  filter(state1 != state2)
  Joining by: c("longitude", "latitude")
  > 
  > pairs
  # A tibble: 74 × 6
     state1      longitude.x latitude.x state2        longitude.y latitude.y
     <chr>             <dbl>      <dbl> <chr>               <dbl>      <dbl>
   1 Alabama           -86.8       32.6 Georgia             -83.4       32.3
   2 Alabama           -86.8       32.6 Mississippi         -89.8       32.7
   3 Connecticut       -72.4       41.6 Massachusetts       -71.6       42.4
   4 Connecticut       -72.4       41.6 New Hampshire       -71.4       43.4
   5 Connecticut       -72.4       41.6 New Jersey          -74.2       40.0
   6 Connecticut       -72.4       41.6 New York            -75.1       43.1
   7 Connecticut       -72.4       41.6 Rhode Island        -71.1       41.6
   8 Connecticut       -72.4       41.6 Vermont             -72.5       44.3
   9 Delaware          -75.0       38.7 Maryland            -76.6       39.3
  10 Delaware          -75.0       38.7 New Jersey          -74.2       40.0
  # ℹ 64 more rows
  > 
  > # plot them
  > library(ggplot2)
  Error in library(ggplot2) : there is no package called ‘ggplot2’
  Execution halted

Check: tests, Result: ERROR
    Running ‘testthat.R’ [1s/1s]
  Running the tests in ‘tests/testthat.R’ failed.
  Complete output:
    > library(testthat)
    > library(fuzzyjoin)
    > 
    > test_check("fuzzyjoin")
    Error in `FUN()`:
    ! In path: "/home/hornik/tmp/CRAN_special_noSuggests/fuzzyjoin.Rcheck/tests/testthat/helper-packages.R"
    Caused by error in `library()`:
    ! there is no package called 'ggplot2'
    Backtrace:
         ▆
      1. ├─testthat::test_check("fuzzyjoin")
      2. │ └─testthat::test_dir(...)
      3. │   └─testthat:::test_files(...)
      4. │     └─testthat:::test_files_serial(...)
      5. │       └─testthat:::test_files_setup_state(...)
      6. │         └─testthat::source_test_helpers(".", env)
      7. │           └─testthat::source_dir(path, "^helper.*\\.[rR]$", env = env, wrap = FALSE)
      8. │             └─base::lapply(...)
      9. │               └─testthat (local) FUN(X[[i]], ...)
     10. │                 └─testthat::source_file(path, env = env, chdir = chdir, wrap = wrap)
     11. │                   ├─base::withCallingHandlers(...)
     12. │                   └─base::eval(exprs, env)
     13. │                     └─base::eval(exprs, env)
     14. │                       ├─base::suppressPackageStartupMessages(library(ggplot2)) at tests/testthat/helper-packages.R:1:1
     15. │                       │ └─base::withCallingHandlers(expr, packageStartupMessage = function(c) tryInvokeRestart("muffleMessage"))
     16. │                       └─base::library(ggplot2)
     17. │                         └─base::stop(packageNotFoundError(package, lib.loc, sys.call()))
     18. └─testthat (local) `<fn>`(`<pckgNtFE>`)
     19.   └─rlang::abort(...)
    Execution halted