Add noduplicates directive#438
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klauspost merged 2 commits intotinylib:masterfrom Apr 17, 2026
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This adds `//msgp:noduplicates [TypeA TypeB ...]` to generator files. This will actively guards against duplicate keys when decoding/unmarshaling structs and maps. Duplicate entries should never be generated as output and generally is no issue unless there is some secondary checks that are inspecting streams (last entry on stream wins). Shimmed keys - late check after shim, before assignment. Catches both identical wire keys AND different wire keys that resolve to the same map key after shimming (e.g. "Foo" vs "foo" with a lowercasing shim). AI Assisted (mostly tests)
philhofer
approved these changes
Apr 16, 2026
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This adds
//msgp:noduplicates [TypeA TypeB ...]to generator files.This will actively guards against duplicate keys when decoding/unmarshaling structs and maps.
Duplicate entries should never be generated as output. The only exception I can think of would be maps with shimming.
Generally duplicate keys is no issue unless there is some secondary checks that are inspecting streams (last entry on stream wins).
Shimmed keys - check keys after shim, before assignment. Catches both identical wire keys AND different wire keys that resolve to the same map key after shimming (e.g. "Foo" vs "foo" with a lowercasing shim).
AI Assisted (mostly tests)