Verify That an Expression Causes an Error

atExpectStop

Description

Evaluate an expression and return TRUE if it throws the expected error message.

Usage

   atExpectStop(expr, expected = ".")

Arguments

expr	An expression to evaluate. It will be taken literally, as in system.time().
expected	A regular expression that matches the expected error message. See regexpr for the syntax; "." matches any message.

Value

TRUE if the expression causes the expected message. Otherwise a string describing the discrepency. This is the type of output that assertionTest requires.

See Also

atExpectWarnings does a similar job for warnings.

Examples

## Not run: 
# The following may be put into a test.t file
# and run by assertionTest.  The first should return TRUE.
atExpectStop(lm(y ~ noSuchData), expected="noSuchData.*not found")
# expect complaints from the following two:
atExpectStop(stop("Oops"), expected="a problem happened")
atExpectStop(1L+2L == 3L, expected="integer arithment overflow")
# Run example test files in assertionTest/test-ex
assertionTest(system.file(package="assertionTest", "test-ex", "allbad.t"))

## End(Not run)

Package assertionTest version 6.1.1-7
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