If I click "Run Last Launched" to reexecute the previously launched JUnit tests after doing some changes in the source code, JUnit will start even through compilation errors are found in the source code just modified. This can cause confusion because the focus is immediately set on the "JUnit" tab, and hence errors listed in the "Problems" tab are hidden. Yep, there is a little red "x" appearing on the Problems tab index, but it can be difficult to spot when the JUnit tab activates itself.

When this condition arises, it would be nice if Eclipse could pop up a modal window saying "The are compilation errors; do you want to launch JUnit anyway?". This behavior is generally found in other IDEs.