AssertionError messages not parsed by IntelliJ

[jcassee]

The current error messages as defined in the default templates are not is a form that IntelliJ parses for diffs:

Expecting someField of:
  <SomeObject>
to be:
  <expected>
but was:
  <actual>

With a slight tweak IntelliJ does parse them and allows you to view the diff:

someField of <SomeObject> expected:<expected> but was:<actual>

I believe Eclipse works the same way. Of course, this might be a bit less nice to read as plain text.

@joel-costigliola Is this something you have considered? Would you accept a pull request for this change?

[joel-costigliola]

I think the best option is to have a template for error messages that would allow users to customize them. The default template would keep the existing message format as we can't assume they will be only consumed from Intellij.

[uhafner]

Seems that assert-core reports messages that could be read by IntelliJ. Just the custom assertions do use a different format (and exception type). Would be nice if the assert-core code could be reused here. (See also comment in https://github.com/joel-costigliola/assertj-core/issues/1144)