all: implement omitempty

Handle the 'omitempty' struct tag similarly to encoding/json

Fixes #263

_generated/omitempty.go

@@ -0,0 +1,177 @@
+package _generated
+
+import "time"
+
+//go:generate msgp
+
+type OmitEmpty0 struct {
+	ABool       bool       `msg:"abool,omitempty"`
+	AInt        int        `msg:"aint,omitempty"`
+	AInt8       int8       `msg:"aint8,omitempty"`
+	AInt16      int16      `msg:"aint16,omitempty"`
+	AInt32      int32      `msg:"aint32,omitempty"`
+	AInt64      int64      `msg:"aint64,omitempty"`
+	AUint       uint       `msg:"auint,omitempty"`
+	AUint8      uint8      `msg:"auint8,omitempty"`
+	AUint16     uint16     `msg:"auint16,omitempty"`
+	AUint32     uint32     `msg:"auint32,omitempty"`
+	AUint64     uint64     `msg:"auint64,omitempty"`
+	AFloat32    float32    `msg:"afloat32,omitempty"`
+	AFloat64    float64    `msg:"afloat64,omitempty"`
+	AComplex64  complex64  `msg:"acomplex64,omitempty"`
+	AComplex128 complex128 `msg:"acomplex128,omitempty"`
+
+	ANamedBool    bool    `msg:"anamedbool,omitempty"`
+	ANamedInt     int     `msg:"anamedint,omitempty"`
+	ANamedFloat64 float64 `msg:"anamedfloat64,omitempty"`
+
+	AMapStrStr map[string]string `msg:"amapstrstr,omitempty"`
+
+	APtrNamedStr *NamedString `msg:"aptrnamedstr,omitempty"`
+
+	AString      string `msg:"astring,omitempty"`
+	ANamedString string `msg:"anamedstring,omitempty"`
+	AByteSlice   []byte `msg:"abyteslice,omitempty"`
+
+	ASliceString      []string      `msg:"aslicestring,omitempty"`
+	ASliceNamedString []NamedString `msg:"aslicenamedstring,omitempty"`
+
+	ANamedStruct    NamedStruct  `msg:"anamedstruct,omitempty"`
+	APtrNamedStruct *NamedStruct `msg:"aptrnamedstruct,omitempty"`
+
+	AUnnamedStruct struct {
+		A string `msg:"a,omitempty"`
+	} `msg:"aunnamedstruct,omitempty"` // omitempty not supported on unnamed struct
+
+	EmbeddableStruct `msg:",flatten,omitempty"` // embed flat
+
+	EmbeddableStruct2 `msg:"embeddablestruct2,omitempty"` // embed non-flat
+
+	AArrayInt [5]int `msg:"aarrayint,omitempty"` // not supported
+
+	ATime time.Time `msg:"atime,omitempty"`
+}
+
+type NamedBool bool
+type NamedInt int
+type NamedFloat64 float64
+type NamedString string
+
+type EmbeddableStruct struct {
+	SomeEmbed string `msg:"someembed,omitempty"`
+}
+
+type EmbeddableStruct2 struct {
+	SomeEmbed2 string `msg:"someembed2,omitempty"`
+}
+
+type NamedStruct struct {
+	A string `msg:"a,omitempty"`
+	B string `msg:"b,omitempty"`
+}
+
+type OmitEmptyHalfFull struct {
+	Field00 string `msg:"field00,omitempty"`
+	Field01 string `msg:"field01"`
+	Field02 string `msg:"field02,omitempty"`
+	Field03 string `msg:"field03"`
+}
+
+type OmitEmptyLotsOFields struct {
+	Field00 string `msg:"field00,omitempty"`
+	Field01 string `msg:"field01,omitempty"`
+	Field02 string `msg:"field02,omitempty"`
+	Field03 string `msg:"field03,omitempty"`
+	Field04 string `msg:"field04,omitempty"`
+	Field05 string `msg:"field05,omitempty"`
+	Field06 string `msg:"field06,omitempty"`
+	Field07 string `msg:"field07,omitempty"`
+	Field08 string `msg:"field08,omitempty"`
+	Field09 string `msg:"field09,omitempty"`
+	Field10 string `msg:"field10,omitempty"`
+	Field11 string `msg:"field11,omitempty"`
+	Field12 string `msg:"field12,omitempty"`
+	Field13 string `msg:"field13,omitempty"`
+	Field14 string `msg:"field14,omitempty"`
+	Field15 string `msg:"field15,omitempty"`
+	Field16 string `msg:"field16,omitempty"`
+	Field17 string `msg:"field17,omitempty"`
+	Field18 string `msg:"field18,omitempty"`
+	Field19 string `msg:"field19,omitempty"`
+	Field20 string `msg:"field20,omitempty"`
+	Field21 string `msg:"field21,omitempty"`
+	Field22 string `msg:"field22,omitempty"`
+	Field23 string `msg:"field23,omitempty"`
+	Field24 string `msg:"field24,omitempty"`
+	Field25 string `msg:"field25,omitempty"`
+	Field26 string `msg:"field26,omitempty"`
+	Field27 string `msg:"field27,omitempty"`
+	Field28 string `msg:"field28,omitempty"`
+	Field29 string `msg:"field29,omitempty"`
+	Field30 string `msg:"field30,omitempty"`
+	Field31 string `msg:"field31,omitempty"`
+	Field32 string `msg:"field32,omitempty"`
+	Field33 string `msg:"field33,omitempty"`
+	Field34 string `msg:"field34,omitempty"`
+	Field35 string `msg:"field35,omitempty"`
+	Field36 string `msg:"field36,omitempty"`
+	Field37 string `msg:"field37,omitempty"`
+	Field38 string `msg:"field38,omitempty"`
+	Field39 string `msg:"field39,omitempty"`
+	Field40 string `msg:"field40,omitempty"`
+	Field41 string `msg:"field41,omitempty"`
+	Field42 string `msg:"field42,omitempty"`
+	Field43 string `msg:"field43,omitempty"`
+	Field44 string `msg:"field44,omitempty"`
+	Field45 string `msg:"field45,omitempty"`
+	Field46 string `msg:"field46,omitempty"`
+	Field47 string `msg:"field47,omitempty"`
+	Field48 string `msg:"field48,omitempty"`
+	Field49 string `msg:"field49,omitempty"`
+	Field50 string `msg:"field50,omitempty"`
+	Field51 string `msg:"field51,omitempty"`
+	Field52 string `msg:"field52,omitempty"`
+	Field53 string `msg:"field53,omitempty"`
+	Field54 string `msg:"field54,omitempty"`
+	Field55 string `msg:"field55,omitempty"`
+	Field56 string `msg:"field56,omitempty"`
+	Field57 string `msg:"field57,omitempty"`
+	Field58 string `msg:"field58,omitempty"`
+	Field59 string `msg:"field59,omitempty"`
+	Field60 string `msg:"field60,omitempty"`
+	Field61 string `msg:"field61,omitempty"`
+	Field62 string `msg:"field62,omitempty"`
+	Field63 string `msg:"field63,omitempty"`
+	Field64 string `msg:"field64,omitempty"`
+	Field65 string `msg:"field65,omitempty"`
+	Field66 string `msg:"field66,omitempty"`
+	Field67 string `msg:"field67,omitempty"`
+	Field68 string `msg:"field68,omitempty"`
+	Field69 string `msg:"field69,omitempty"`
+}
+
+type OmitEmpty10 struct {
+	Field00 string `msg:"field00,omitempty"`
+	Field01 string `msg:"field01,omitempty"`
+	Field02 string `msg:"field02,omitempty"`
+	Field03 string `msg:"field03,omitempty"`
+	Field04 string `msg:"field04,omitempty"`
+	Field05 string `msg:"field05,omitempty"`
+	Field06 string `msg:"field06,omitempty"`
+	Field07 string `msg:"field07,omitempty"`
+	Field08 string `msg:"field08,omitempty"`
+	Field09 string `msg:"field09,omitempty"`
+}
+
+type NotOmitEmpty10 struct {
+	Field00 string `msg:"field00"`
+	Field01 string `msg:"field01"`
+	Field02 string `msg:"field02"`
+	Field03 string `msg:"field03"`
+	Field04 string `msg:"field04"`
+	Field05 string `msg:"field05"`
+	Field06 string `msg:"field06"`
+	Field07 string `msg:"field07"`
+	Field08 string `msg:"field08"`
+	Field09 string `msg:"field09"`
+}