While I've been a fan of
Groovy for some time, I wasn't a fan of
assert in Groovy,
it produced a big ugly stack trace and wasn't very readable. So I just ignored
assert
as I have in Java.
Most developers ignore
assert in Java, it was introduced late, it's complicated to work
with from a tuning and performance perspective, we've been doing unit testing long before
assert was introduced...
However the core Groovy community loves
assert, almost all example code for Groovy,
beyond 'Hello World', uses
assert to show what's going on. Example:
Introduction to Groovy
So ignoring
assert in Groovy, didn't feel very groovy; I was at odds with the community. Using
assert didn't feel groovy either.
That changed last night as I debugging some code for the build system. I put in a quick
assert as a sanity check and it failed, but it failed beautifully. It produced one of the most beautiful error messages I've ever seen, it looked something like:
assert demo.calcA() == demo.calcB()
| | | | |
| 1 | | 2
| | AssertDemo@2c79809
| false
AssertDemo@2c79809
The perfect amount of information, quickly showing me what was happening in my code.
Turns out Groovy 1.7 introduced
Power Asserts because
Groovy's "assert" keyword has sometimes been criticized as it's, in a way, limited, as it just checks that the expression it's being passed is true or false. Unlike with testing frameworks such as JUnit/TestNG and the various additional assertion utilities, where you get nicer and more descriptive messages, Groovy's assert would just tell you the expression was false, and would give the value of variables used in the expression, but nothing more.
OK, so I'm not quite alone in my lack of love for the old
assert. The new Power Assert is a thing of beauty.
Power Assert was developed as part of
Spock: a testing and specification framework for Java and Groovy applications. I haven't used Spock, but it's now on the list of things to check out.
- Peace
