code_calls: Check whether code calls a desired function or object

In garrettgman/magrader: A simple checking scheme for tutor based on magrittr pipes

Description

'code_calls()' is designed to be used in a magrittr pipe. It will first check whether the code input has a;lready failed a previous check. If it has not, 'code_calls()' will check to see whether the code calls the given object or function.

Usage

code_calls(submission, call, message = paste("I expected to see a call to",
  call), warn = FALSE, praise = NULL)

Arguments

submission	The code to check, as a character string, or the output of a previous check function. If you are using 'code_calls()' within a tutor document, set code to the special name '.answer'.
call	The name of a function or object to check for as a character string.
message	A character string of feedback to display if the code fails the check
warn	'TRUE' or 'FALSE': should grading continue if condition is unmet? If 'TRUE', 'code_calls()' will mark the submission as a warning and pass the submission to the next check in the checking pipe. In this case, 'code_calls()' will append the message to the list of messages to be displayed when checking completes.
praise	A character string of feedback to display if the code passes the check. If a submission receives more than one praise. When checking finishes, magrader will display all of the warnings and praises that have accumulated for a submission.

Value

If the code passes the check, 'code_calls()' returns the original code. If the code fails the check, 'code_calls()' returns a failure object that contains a feedback message.

Examples

## Not run: 
"head(mtcars)" %>%
  code_calls("head") %>%
  code_calls("mpg", "oops, wrong data set.")

# If in a tutor document
.answer %>%
  code_calls("head") %>%
  code_calls("mpg", "oops, wrong data set.")

## End(Not run)

garrettgman/magrader documentation built on May 16, 2019, 5:39 p.m.