Document why UnexpectedNilError inherits from Exception#21
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| # WARNING: do NOT change the superclass to `StandardError`. | ||
| # Doing so would allow common `rescue StandardError` or bare `rescue` clauses to silently swallow | ||
| # nil errors, masking bugs that should be immediately visible. |
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I don't think this is particularly relevant to the gem.
A gem user can't change it unless they make their own copy, which isn't our problem
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| # WARNING: do NOT change the superclass to `StandardError`. | |
| # Doing so would allow common `rescue StandardError` or bare `rescue` clauses to silently swallow | |
| # nil errors, masking bugs that should be immediately visible. |
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UnexpectedNilError inherits from Exception
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Prompted by a real-world case where a copy of
UnexpectedNilErrorin another codebase changed the superclass toStandardError, which caused nil errors to be silently swallowed by commonrescue StandardErrorclauses in tests — masking bugs that should have been immediately visible.The existing comment explained the rationale but didn't warn against this specific footgun. This PR:
rescue Exceptioncan still catch it (intentionally harder to do accidentally)Related: #20