Include messages while testing signaling conditions

[IndrajeetPatil]

Currently, most of the tests that check for signaling conditions (messages, warnings, or errors) are only testing if the conditions occur. But we should be additionally capturing the condition messages to ensure that the condition was produced for expected reasons, and not for some other, unexpected reasons.

expect_error(), expect_warning(), and expect_message() all have a regexp argument for this.

# current
expect_error(f(x))

# should be
expect_error(f(x), "....")

For example, see this test from {datawizard}.

Progress tracker:

• insight
• modelbased
• bayestestR
• effectsize
• parameters
• performance
• correlation
• report
• see
• datawizard
• easystats

[strengejacke]

Note that since we often use format_message(), which wraps lines of the messages to fit to the given width of the console (or whereever the output is streamed to). And the system where tests are run often have different "line length", so never check against the complete string. It's better to have just a few words, the safest is to have just one (key-) word from the message.

[IndrajeetPatil]

Yepp, that's what's happening in {datawizard}; using just a single word or few words in regexp argument.

That said, my personal preference is to use snapshots here to make sure that the messages are formatted and printed as expected, but I know how you feel about snapshot testing 🙃

[strengejacke]

I know how you feel about snapshot testing

I literally invented them.