## Crater report analysis

*Context: We did a crater run were we temporarily put the lint to deny-by-default, and here are the results.*

Affected projects: 7057 / 851203 (0.82%)
Total errors: 116165

Total errors from derive macros: 107531 (across 259 different derive macros)
Total errors from macro_rules!: 2150 (across 117 different `macro_rules!`)
Total errors (manual, not above): 6484

### Derive macros

<details>

Total errors from derive macros **fixed upstream**: 84315 (78.4%)
Total errors from derive macros **NOT fixed upstream**: 12660 (11.8%)
Total errors from derive macros **deprecated**: 5397 (5.0%)
Total errors from derive macros **uncategorised**: 5159 (4.8%)

- `Deserialize`: 26154 (status: fixed in serde_derive)
- `QueryId`: 25116 (status: fixed in diesel_derives)
- `Serialize`: 20385 (status: fixed in serde_derive)
- `Fail`: 5303 (status: deprecated)
- `FromPrimitive`: 4649 (status: not-fixed)
- `Queryable`: 3570 (status: fixed in diesel_derives)
- `Insertable`: 2889 (status: fixed in diesel_derives)
- `ToPrimitive`: 2010 (status: not-fixed)
- `YaDeserialize`: 1454 (status: not-fixed)
- `YaSerialize`: 1424 (status: not-fixed)
- `Identifiable`: 1159 (status: fixed in diesel_derives)
- `PeekPoke`: 822 (status: not-fixed)
- `Trace`: 810 (status: fixed in gc)
- `AsChangeset`: 763 (status: fixed in diesel_derives)
- `Error`: 738 (status: not-fixed)
- `Collect`: 730 (status: fixed in gc-arena-derive)
- `Display`: 566 (status: not-fixed)
- `Endpoint`: 468 (status: not-fixed)
- `Finalize`: 405 (status: fixed in gc)
- `serde::Deserialize`: 386 (status: fixed in serde_derive)
- `Associations`: 347 (status: fixed in diesel_derives)
- `serde::Serialize`: 315 (status: fixed in serde_derive)
- `Command`: 305 (status: fixed in structopt)
- `Savefile`: 296 (status: not-fixed)
- `FromPest`: 270 (status: fixed in from-pest)
- `Abomonation`: 262 (status: n/a)
- `Arbitrary`: 257 (status: n/a)
- `sp::FieldOffsets`: 210 (status: n/a)
- `DieselNumericOps`: 184 (status: fixed in diesel_derives)
- `QueryableByName`: 176 (status: fixed in diesel_derives)
- `displaydoc::Display`: 159 (status: n/a)
- `num_derive::FromPrimitive`: 152 (status: not-fixed)
- `proptest_derive::Arbitrary`: 151 (status: n/a)
- `WidgetCommon_`: 136 (status: n/a)
- `FromSqlRow`: 126 (status: n/a)
- `TlWrite`: 126 (status: n/a)
- `StructOpt`: 123 (status: fixed in structopt)
- `serde_derive::Deserialize`: 120 (status: fixed in serde_derive)
- `Protocol`: 117 (status: n/a)
- `TlRead`: 110 (status: n/a)
- `serde_derive::Serialize`: 108 (status: fixed in serde_derive)
- `WidgetStyle_`: 104 (status: n/a)
- `Sparsable`: 103 (status: n/a)
- `sixtyfps::re_exports::FieldOffsets`: 100 (status: n/a)
- `AsExpression`: 98 (status: n/a)
- `HasInterner`: 98 (status: n/a)
- `OApiCheck`: 98 (status: n/a)
- `Zeroize`: 97 (status: n/a)
- `failure::Fail`: 94 (status: deprecated)
- `err_derive::Error`: 88 (status: n/a)
- `FieldOffsets`: 87 (status: n/a)
- `num_derive::ToPrimitive`: 81 (status: not-fixed)
- `Fold`: 70 (status: n/a)
- `Header`: 70 (status: n/a)
- `Runnable`: 69 (status: n/a)
- `custom_debug_derive::Debug`: 66 (status: n/a)
- `OApiExt`: 66 (status: n/a)
- `Debug`: 65 (status: n/a)
- `Message`: 60 (status: n/a)
- `near_sdk::serde::Serialize`: 60 (status: n/a)
- `Recap`: 59 (status: n/a)
- `Visit`: 56 (status: n/a)
- `slint::re_exports::FieldOffsets`: 52 (status: n/a)
- `custom_debug::Debug`: 48 (status: n/a)
- `SqlType`: 44 (status: n/a)
- `ZeroizeOnDrop`: 44 (status: n/a)
- `H5Type`: 43 (status: n/a)
- `MontConfig`: 42 (status: n/a)
- `AstClone`: 42 (status: n/a)
- `debug2::Debug`: 40 (status: n/a)
- `Value`: 38 (status: n/a)
- `BartDisplay`: 37 (status: n/a)
- `diesel::Queryable`: 36 (status: n/a)
- `OpgModel`: 36 (status: n/a)
- `Encode`: 35 (status: n/a)
- `Decode`: 35 (status: n/a)
- `QueryEndpoint`: 34 (status: n/a)
- `RequestContext`: 32 (status: n/a)
- `GraphQLInputObject`: 32 (status: n/a)
- `Zip`: 32 (status: n/a)
- `Scan`: 31 (status: n/a)
- `Gtmpl`: 30 (status: n/a)
- `VmType`: 28 (status: n/a)
- `::pin_project::__private::__PinProjectInternalDerive`: 28 (status: n/a)
- `slint::private_unstable_api::re_exports::FieldOffsets`: 28 (status: n/a)
- `DieselNewType`: 27 (status: n/a)
- `FromRequest`: 27 (status: n/a)
- `potatonet::serde_derive::Serialize`: 26 (status: n/a)
- `potatonet::serde_derive::Deserialize`: 26 (status: n/a)
- `CustomDebug`: 26 (status: n/a)
- `Prim`: 26 (status: n/a)
- `BoundTerm`: 25 (status: n/a)
- `IntEnum`: 24 (status: n/a)
- `ark_ff::MontConfig`: 23 (status: n/a)
- `ArrowDeserialize`: 23 (status: n/a)
- `WidgetCommon`: 20 (status: n/a)
- `ErrorKind`: 20 (status: n/a)
- `Model`: 19 (status: n/a)
- `diesel::Identifiable`: 18 (status: n/a)
- `AppRoute`: 16 (status: n/a)
- `Hash32`: 16 (status: n/a)
- `WidgetStyle`: 16 (status: n/a)
- `ModuleBase`: 16 (status: n/a)
- `Component`: 14 (status: n/a)
- `quickcheck_derive::Arbitrary`: 14 (status: n/a)
- `gio::glib::ValueDelegate`: 14 (status: n/a)
- `GC`: 13 (status: n/a)
- `glib::Variant`: 13 (status: n/a)
- `Getable`: 13 (status: n/a)
- `Zero`: 13 (status: n/a)
- `One`: 13 (status: n/a)
- `Num`: 13 (status: n/a)
- `Odbc`: 12 (status: n/a)
- `OscMessage`: 12 (status: n/a)
- `Dbg`: 12 (status: n/a)
- `Enumeration`: 12 (status: n/a)
- `diesel::Insertable`: 12 (status: n/a)
- `common::serde::SerializeWithCtx`: 12 (status: n/a)
- `DebugWithCtx`: 12 (status: n/a)
- `Pushable`: 11 (status: n/a)
- `Table`: 11 (status: n/a)
- `PrefixOpt`: 11 (status: n/a)
- `ConstructorMacro`: 10 (status: n/a)
- `hdf5::H5Type`: 10 (status: n/a)
- `Encodable`: 10 (status: n/a)
- `FromDynamic`: 10 (status: n/a)
- `diesel::Associations`: 10 (status: n/a)
- `ToDynamic`: 9 (status: n/a)
- `AironeDbDerive`: 8 (status: n/a)
- `FiniteAutomataConstructor`: 8 (status: n/a)
- `hash32_derive::Hash32`: 8 (status: n/a)
- `NewFuzzed`: 8 (status: n/a)
- `NumCast`: 8 (status: n/a)
- `Float`: 8 (status: n/a)
- `StructDeser`: 8 (status: n/a)
- `::num_derive::FromPrimitive`: 8 (status: n/a)
- `::num_derive::ToPrimitive`: 8 (status: n/a)
- `abomonation_derive::Abomonation`: 8 (status: n/a)
- `SuperFoldable`: 8 (status: n/a)
- `Alga`: 7 (status: n/a)
- `gff_derive::GFFStruct`: 7 (status: n/a)
- `Zvt`: 7 (status: n/a)
- `$crate::codec::Encode`: 7 (status: n/a)
- `$crate::codec::Decode`: 7 (status: n/a)
- `ValueDelegate`: 6 (status: n/a)
- `Userdata`: 6 (status: n/a)
- `KittyCommand`: 6 (status: n/a)
- `BoundPattern`: 6 (status: n/a)
- `Into`: 6 (status: n/a)
- `TypeInfo`: 6 (status: n/a)
- `TypeDesc`: 6 (status: n/a)
- `DerSequence`: 6 (status: n/a)
- `miniserde::Serialize`: 6 (status: n/a)
- `GraphQLEnum`: 6 (status: n/a)
- `opg::OpgModel`: 6 (status: n/a)
- `CustumDebug`: 6 (status: n/a)
- `ResultLike`: 5 (status: n/a)
- `OptionLike`: 5 (status: n/a)
- `SparsableInner`: 5 (status: n/a)
- `PropTestArbitrary`: 5 (status: n/a)
- `microserde::Serialize`: 4 (status: n/a)
- `cs::Debug`: 4 (status: n/a)
- `ViaSerialize`: 4 (status: n/a)
- `ViaDeserialize`: 4 (status: n/a)
- `tl_proto::TlRead`: 4 (status: n/a)
- `tl_proto::TlWrite`: 4 (status: n/a)
- `Key`: 4 (status: n/a)
- `Uniform`: 4 (status: n/a)
- `LambdaErrorExt`: 4 (status: n/a)
- `failure_derive::Fail`: 4 (status: n/a)
- `Absorb`: 4 (status: n/a)
- `Emit`: 4 (status: n/a)
- `Serializer`: 4 (status: n/a)
- `diesel_derive_newtype::DieselNewType`: 4 (status: n/a)
- `DocDefault`: 4 (status: n/a)
- `Interpolate`: 4 (status: n/a)
- `StableAbi`: 4 (status: n/a)
- `diesel::QueryableByName`: 4 (status: n/a)
- `Bson`: 4 (status: n/a)
- `SuperVisit`: 4 (status: n/a)
- `diesel::AsExpression`: 4 (status: n/a)
- `diesel::FromSqlRow`: 4 (status: n/a)
- `::cliff::serde::Serialize`: 4 (status: n/a)
- `::cliff::serde::Deserialize`: 4 (status: n/a)
- `Foldable`: 4 (status: n/a)
- `serde1::Deserialize`: 4 (status: n/a)
- `serde2::Deserialize`: 4 (status: n/a)
- `EnumToStr`: 3 (status: n/a)
- `elise::GC`: 3 (status: n/a)
- `EnumDisplay`: 3 (status: n/a)
- `Coerce`: 3 (status: n/a)
- `glib::Enum`: 3 (status: n/a)
- `IriEnum`: 3 (status: n/a)
- `Document`: 3 (status: n/a)
- `Limit`: 3 (status: n/a)
- `ReParse`: 3 (status: n/a)
- `From`: 3 (status: n/a)
- `Config`: 2 (status: n/a)
- `derive_resource_impl`: 2 (status: n/a)
- `$crate::diesel_derive_newtype::DieselNewType`: 2 (status: n/a)
- `Lens`: 2 (status: n/a)
- `rkyv::Deserialize`: 2 (status: n/a)
- `GridCell`: 2 (status: n/a)
- `GantzNode_`: 2 (status: n/a)
- `Bake`: 2 (status: n/a)
- `glib::SharedBoxed`: 2 (status: n/a)
- `glib::Boxed`: 2 (status: n/a)
- `gluon_codegen::AstClone`: 2 (status: n/a)
- `DagCbor`: 2 (status: n/a)
- `Extract`: 2 (status: n/a)
- `Response`: 2 (status: n/a)
- `protocol::Protocol`: 2 (status: n/a)
- `der::Message`: 2 (status: n/a)
- `Unsigned`: 2 (status: n/a)
- `Signed`: 2 (status: n/a)
- `Cacheable`: 2 (status: n/a)
- `DisplayDoc`: 2 (status: n/a)
- `::pin_project::__private::__PinProjectAutoImplUnpin`: 2 (status: n/a)
- `TrackableError`: 2 (status: n/a)
- `const_field_offset::FieldOffsets`: 2 (status: n/a)
- `miniserde::Deserialize`: 2 (status: n/a)
- `self::sr_api_hidden_includes_decl_storage::hidden_include::codec::Encode`: 2 (status: n/a)
- `self::sr_api_hidden_includes_decl_storage::hidden_include::codec::Decode`: 2 (status: n/a)
- `self::sr_api_hidden_includes_decl_storage::hidden_include::Serialize`: 2 (status: n/a)
- `self::sr_api_hidden_includes_decl_storage::hidden_include::Deserialize`: 2 (status: n/a)
- `ElasticType`: 2 (status: n/a)
- `SerializeState`: 2 (status: n/a)
- `Vertex`: 2 (status: n/a)
- `Uniforms`: 2 (status: n/a)
- `recap::Recap`: 2 (status: n/a)
- `asn1_rs::DerSequence`: 2 (status: n/a)
- `FromInner`: 2 (status: n/a)
- `CompactTypeId`: 2 (status: n/a)
- `NamedType`: 2 (status: n/a)
- `int_enum::IntEnum`: 2 (status: n/a)
- `scale_info::TypeInfo`: 2 (status: n/a)
- `bart_derive::BartDisplay`: 1 (status: n/a)
- `MultihashDigest`: 1 (status: n/a)
- `EnumTryInto`: 1 (status: n/a)
- `ParquetRecordWriter`: 1 (status: n/a)
- `zvariant::OwnedValue`: 1 (status: n/a)
- `Hashable`: 1 (status: n/a)
- `IntoPrimitive`: 1 (status: n/a)
- `GuestType`: 1 (status: n/a)
- `Instruments`: 1 (status: n/a)
- `LogicStruct`: 1 (status: n/a)
- `AsStd140`: 1 (status: n/a)
- `FinalizeFields`: 1 (status: n/a)
- `Multihash`: 1 (status: n/a)
- `Builder`: 1 (status: n/a)
- `Synonym`: 1 (status: n/a)
- `WrappedVec`: 1 (status: n/a)
- `DatastoreManaged`: 1 (status: n/a)
- `CEnum`: 1 (status: n/a)
- `FilterNodes`: 1 (status: n/a)
- `Parse`: 1 (status: n/a)
- `Spanned`: 1 (status: n/a)
- `MiniSerialize`: 1 (status: n/a)
- `MiniDeserialize`: 1 (status: n/a)

</details>

### `macro_rules!`

<details>

- `$crate::py_class_impl`: 208
- `$crate::_pair`: 168
- `ComponentVTable_static`: 168
- `$crate::_single`: 108
- `$crate::impl_mul_for_primitive`: 100
- `$crate::pyobject_native_type_named`: 96
- `$crate::__private_maparr`: 88
- `implement_vertex`: 78
- `_pyo3::impl_::pyclass::generate_pyclass_richcompare_slot`: 66
- `$crate::impl_dyn_cast_config`: 57
- `ItemTreeVTable_static`: 56
- `$crate::impl_dyn_cast`: 54
- `$crate::impl_try_from_for_primitive`: 50
- `$crate::construct_uint`: 35
- `$crate::impl_exception_boilerplate`: 32
- `$crate::pyobject_native_type_extract`: 32
- `$crate::__define_v_table_internal`: 32
- `$crate::__internal_clone_trait_object`: 24
- `enum_unitary`: 24
- `impl_point_and_envelope`: 24
- `::cast_trait_object::impl_dyn_cast_config`: 24
- `eager_macro_rules_internal`: 22
- `impl_trait`: 20
- `test_binary`: 20
- `add_from`: 20
- `flash_impl`: 19
- `$crate::define_udt`: 18
- `lex_rule`: 18
- `$crate::glib_object_wrapper`: 16
- `value_enum`: 16
- `impl_unsigned_varint`: 16
- `$crate::impl_serialize_primitive`: 16
- `$crate::impl_state_primitive`: 16
- `$crate::impl_meta_primitive`: 16
- `impl_signed_varint`: 16
- `signed`: 15
- `unsigned`: 15
- `define_ext`: 12
- `create_lineariseable_data_type`: 12
- `manual`: 12
- `flexible`: 12
- `create_color_matcher_or_alterator`: 12
- `bitflags_set`: 12
- `$crate::impl_mul_from`: 10
- `construct_uint`: 10
- `scoped_thread_local`: 10
- `integer_array::declare_array_real`: 9
- `declare_array_real`: 9
- `impl_dyn_cast`: 9
- `impl_poem_type`: 8
- `scoped_tls_hkt::scoped_thread_local`: 8
- `::cast_trait_object::impl_dyn_cast`: 8
- `glium::implement_vertex`: 8
- `codegen_define_method`: 8
- `define_str_enum`: 8
- `library`: 7
- `rkyv_dyn::register_impl`: 6
- `holochain_serial`: 6
- `float`: 6
- `define_q_num`: 6
- `crate::impl_dyn_cast`: 6
- `reflect::library`: 5
- `zerocopy_value_codec`: 5
- `make_from_iterator`: 4
- `py_class_impl`: 4
- `__array_impls`: 4
- `basic`: 4
- `class_extends`: 4
- `crate::class_extends`: 4
- `make_header`: 4
- `test_unary`: 4
- `singleton_backcompat`: 4
- `stringy`: 4
- `$crate::_internal_impl_common`: 4
- `rustler::resource`: 4
- `baseplug::model`: 4
- `$crate::env_config`: 4
- `metamodel_macros::generate_model_from_tuple`: 4
- `max_impl`: 4
- `$crate::__declare_length_type_and_pass`: 3
- `$crate::new_error_struct`: 3
- `define_ranged_enum`: 3
- `amethyst_assets::register_format_type`: 2
- `impl_poem_parameter`: 2
- `enhanced_enum`: 2
- `utils::ident_str`: 2
- `ident_str`: 2
- `from_prim`: 2
- `print_item_resolve_later_demonstration`: 2
- `prost_into_vec`: 2
- `vec_try_into_prost`: 2
- `prost_into_bytes`: 2
- `declare_new_type`: 2
- `impl_SliceIndex`: 2
- `inventory::collect`: 2
- `impl_noop_disconnect_and_handshake`: 2
- `impl_from_num_for_json`: 2
- `assoc_static`: 1
- `autofolder_impl_foldertrait`: 1
- `autofolder_impl_reducetrait`: 1
- `$crate::__c_enum_no_debug`: 1
- `plugin_registry`: 1
- `$crate::new_error_enum`: 1
- `crate::constrained_string`: 1
- `clamp`: 1
- `bytes_try_into_prost`: 1
- `newtype`: 1
- `derive_display_from_serialize`: 1
- `derive_serialize_from_display`: 1
- `$crate::assoc_static`: 1
- `$crate::assoc_threadlocal`: 1
- `$crate::stack`: 1
- `derive_AsRef_for_auto_trait_combination`: 1
- `derive_AsMut_for_auto_trait_combination`: 1
- `$crate::bitfield_without_debug`: 1
- `deprecated_from`: 1
- `specification`: 1

</details>

### Manual (not derive or macro_rules!)

<details>

Inside:
- `function`: 2357
- `method`: 1866
- `constant`: 1800
- `static`: 180
- `async block`: 139
- `associated function`: 80
- `async fn`: 32
- `closure`: 22
- `associated constant`: 8

</details>

------

### Summary

In conclusion, this crater run revealed that making the lint deny-by-default (which is NOT default that would would be used, it would be warn-by-default) would break 7057 crates / 851203 crates tested (0.82%), there was a total of 116165 errors, of which 107531 (92.6%) errors were coming from derives macros, 2150 were coming from `macro_rules!` and 6484 errors are not coming from either of them.

Analysing the root of those derives and macros revealed many outdated versions of `serde_derive` and `diesel_derives`, representing nearly 74% of the total errors alone, as well 6 different derive crates that represent 11.4% that would need to be updated.

To put it simply:

- 84523 (76.3%) errors would be fixed by `cargo update` (representing 6104 different crates)
- 12660 (11.4%) errors that could fixed by upstream change (at least 6 different derive crates)
- 6484 (5.9%) errors requires manual intervention (788 different crates)
- 7309 (6.6%) uncategorised errors (probably manual intervention and deps change):

The author of this PR (@Urgau) thinks those are acceptable numbers, in more that 3/4 of cases a `cargo update` would fix the warnings and by fixing 6 different derives we could get to 90%, the rest of cases would need manual interventions, but some intervention are to be expected.

*Reminder that the lint is warn-by-default, so it wouldn't break anyone!*