def METHOD_NAME(self):
    st = f.IssueTrackerFactory(tracker_product=self.tracker_product)
    st.issue_report_params = "product=name"
    self.assertValidationError(
        "issue_report_params",
        r"Line .+ is not a pair of key/value separated by ':'",
        st.full_clean,
    )
    st = f.IssueTrackerFactory(tracker_product=self.tracker_product)
    st.issue_report_params = "product: name\ncustom_field: a:b:c"
    self.assertValidationError(
        "issue_report_params", r"Line .+ contains multiple ':'", st.full_clean
    )