It appears that on some Rails source code containing model object creation login, IDEA 7.0.4 with Ruby plugin version 1.5.18930 will definitely hang and CPUs reach 100% if I click or do anything right after the dot character of some object or an equal character within that code.
This is a sample code that can make IDEA hang. Sorry I haven't tried this code with a different and lighter project to see if IDEA also hangs. The source code is bad but that should not be the reason for IDEA to hang.
for project_language in project_languages
if checkedItem.to_i == project_language.language_id
existing = true
proj_lang = ProjectLanguage.new
proj_lang.project_id = project_id
proj_lang.language_id = params["item" + i.to_s]["checked"]
proj_lang.position = position
i += 1