Ensure exhaustive switch statements #164
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PR sibprogrammer#162 revealed that missing node type handlers in switch statements cause silent data loss - CDATA content was being dropped because CharDataNode wasn't handled. This PR adds defensive programming to prevent this entire class of bug. Changes: - Added exhaustive switch coverage for all xmlquery.NodeType values - Added exhaustive switch coverage for xml.Token and html.TokenType - Added exhaustive switch coverage for json.Token and json.Delim - Added default cases with panic() to all exhaustive switches - Added explicit documented defaults to intentionally non-exhaustive switches This follows the Go stdlib pattern (runtime/panic.go, go/types) of using panic("unreachable") for "should be impossible" states. If future xmlquery versions add new node types, or if we overlook a handler, tests will fail immediately rather than silently corrupting output. All switches now explicitly handle defaults: - 8 exhaustive switches panic on unknown values - 7 non-exhaustive switches have documented intentional behavior Added TestExhaustiveNodeTypeHandling to verify all node types are processed without panicking. All existing tests pass. This is a non-breaking change - no API modifications, only defensive additions to switch statements. Related: sibprogrammer#162
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PR #162 revealed that missing node type handlers in switch statements
cause silent data loss - CDATA content was being dropped because
CharDataNode wasn't handled. This PR adds defensive programming to
prevent this entire class of bug.
Changes:
This follows the Go stdlib pattern (runtime/panic.go, go/types) of using
panic("unreachable") for "should be impossible" states. If future xmlquery
versions add new node types, or if we overlook a handler, tests will fail
immediately rather than silently corrupting output.
All switches now explicitly handle defaults:
Added TestExhaustiveNodeTypeHandling to verify all node types are
processed without panicking. All existing tests pass.
This is a non-breaking change - no API modifications, only defensive
additions to switch statements.
Related: #162