The bug appeared when we turned “ultra light classes” on by default.
The difference with the old implementation is that
PsiClass.getTextRange() returns the correct non-null value.
This triggers JavaExecutionUtil#stepIntoSingleClass() to return
a light class instead of the original location (of a PsiIdentifier).
So AbstractJavaTestConfigurationProducer#isConfigurationFromContext()
returns true, and the wrong configuration is reused instead of
creating the new one.
By the way, for Java it also returns an identifier because of the
PsiTreeUtil.getParentOfType(element, PsiClass.class) != null check.
The proper fix should land in the newer versions of IDEA, however this
(hopefully, temporary) hack will fix test method gutters for
all platform versions.
Yan Zhulanow
390d062721