| has_message {testit} | R Documentation |
Test whether an expression signals a condition
Description
Check if evaluating an expression produces a message, warning, or error.
These functions are designed to be used inside assert() to verify that code
signals the expected conditions. Optionally, you can match against the
condition's text to ensure the right message/warning/error was signaled.
Usage
has_message(expr, message = NULL, ...)
has_warning(expr, message = NULL, ...)
has_error(expr, message = NULL, ...)
Arguments
expr |
An R expression to evaluate. |
message |
An optional string to match against the condition text. Uses
fixed (literal) matching by default. If provided, the function returns
|
... |
Additional arguments passed to |
Value
TRUE if the condition was signaled (and the message matched, if
provided), FALSE otherwise.
Examples
has_message(message('hello'))
has_message(1 + 1)
has_message(message('hello world'), 'hello')
has_warning(1 + 1)
has_warning(1:2 + 1:3)
has_warning(1:2 + 1:3, 'longer object length')
has_error(2 - 3)
has_error(1 + 'a')
has_error(stop('err'), 'err')
has_error(stop('error occurred'), 'error')