Run a single example group in RSpec
To only run a single describe/context block in a long spec, you can say
spec spec/models/note_spec.rb:545
... where the describe block starts at line 545.
Note: This will only run examples that are direct children of this block, not descendants further down (when nesting describe/context blocks).
You may also pass the line of an it block to run this exact one.
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