reflection: WIP

Signed-off-by: Alejandro Mery <amery@jpi.io>

go.mod

@@ -2,21 +2,22 @@ module asciigoat.org/core
 
 go 1.19
 
-require github.com/mgechev/revive v1.3.3
+require (
+	github.com/fatih/structtag v1.2.0
+	github.com/mgechev/revive v1.3.3
+	github.com/pkg/errors v0.9.1
+)
 
 require (
 	github.com/BurntSushi/toml v1.3.2 // indirect
-	github.com/chavacava/garif v0.1.0 // indirect
+	github.com/chavacava/garif v0.0.0-20230608123814-4bd63c2919ab // indirect
 	github.com/fatih/color v1.15.0 // indirect
-	github.com/fatih/structtag v1.2.0 // indirect
 	github.com/mattn/go-colorable v0.1.13 // indirect
-	github.com/mattn/go-isatty v0.0.19 // indirect
+	github.com/mattn/go-isatty v0.0.17 // indirect
-	github.com/mattn/go-runewidth v0.0.15 // indirect
+	github.com/mattn/go-runewidth v0.0.9 // indirect
 	github.com/mgechev/dots v0.0.0-20210922191527-e955255bf517 // indirect
 	github.com/mitchellh/go-homedir v1.1.0 // indirect
 	github.com/olekukonko/tablewriter v0.0.5 // indirect
-	github.com/pkg/errors v0.9.1 // indirect
-	github.com/rivo/uniseg v0.4.4 // indirect
 	golang.org/x/sys v0.11.0 // indirect
 	golang.org/x/tools v0.12.0 // indirect
 )

go.sum

@@ -1,7 +1,7 @@
 github.com/BurntSushi/toml v1.3.2 h1:o7IhLm0Msx3BaB+n3Ag7L8EVlByGnpq14C4YWiu/gL8=
 github.com/BurntSushi/toml v1.3.2/go.mod h1:CxXYINrC8qIiEnFrOxCa7Jy5BFHlXnUU2pbicEuybxQ=
-github.com/chavacava/garif v0.1.0 h1:2JHa3hbYf5D9dsgseMKAmc/MZ109otzgNFk5s87H9Pc=
+github.com/chavacava/garif v0.0.0-20230608123814-4bd63c2919ab h1:5JxePczlyGAtj6R1MUEFZ/UFud6FfsOejq7xLC2ZIb0=
-github.com/chavacava/garif v0.1.0/go.mod h1:XMyYCkEL58DF0oyW4qDjjnPWONs2HBqYKI+UIPD+Gww=
+github.com/chavacava/garif v0.0.0-20230608123814-4bd63c2919ab/go.mod h1:XMyYCkEL58DF0oyW4qDjjnPWONs2HBqYKI+UIPD+Gww=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
@@ -12,11 +12,10 @@ github.com/fatih/structtag v1.2.0/go.mod h1:mBJUNpUnHmRKrKlQQlmCrh5PuhftFbNv8Ys4
 github.com/mattn/go-colorable v0.1.13 h1:fFA4WZxdEF4tXPZVKMLwD8oUnCTTo08duU7wxecdEvA=
 github.com/mattn/go-colorable v0.1.13/go.mod h1:7S9/ev0klgBDR4GtXTXX8a3vIGJpMovkB8vQcUbaXHg=
 github.com/mattn/go-isatty v0.0.16/go.mod h1:kYGgaQfpe5nmfYZH+SKPsOc2e4SrIfOl2e/yFXSvRLM=
-github.com/mattn/go-isatty v0.0.19 h1:JITubQf0MOLdlGRuRq+jtsDlekdYPia9ZFsB8h/APPA=
+github.com/mattn/go-isatty v0.0.17 h1:BTarxUcIeDqL27Mc+vyvdWYSL28zpIhv3RoTdsLMPng=
-github.com/mattn/go-isatty v0.0.19/go.mod h1:W+V8PltTTMOvKvAeJH7IuucS94S2C6jfK/D7dTCTo3Y=
+github.com/mattn/go-isatty v0.0.17/go.mod h1:kYGgaQfpe5nmfYZH+SKPsOc2e4SrIfOl2e/yFXSvRLM=
+github.com/mattn/go-runewidth v0.0.9 h1:Lm995f3rfxdpd6TSmuVCHVb/QhupuXlYr8sCI/QdE+0=
 github.com/mattn/go-runewidth v0.0.9/go.mod h1:H031xJmbD/WCDINGzjvQ9THkh0rPKHF+m2gUSrubnMI=
-github.com/mattn/go-runewidth v0.0.15 h1:UNAjwbU9l54TA3KzvqLGxwWjHmMgBUVhBiTjelZgg3U=
-github.com/mattn/go-runewidth v0.0.15/go.mod h1:Jdepj2loyihRzMpdS35Xk/zdY8IAYHsh153qUoGf23w=
 github.com/mgechev/dots v0.0.0-20210922191527-e955255bf517 h1:zpIH83+oKzcpryru8ceC6BxnoG8TBrhgAvRg8obzup0=
 github.com/mgechev/dots v0.0.0-20210922191527-e955255bf517/go.mod h1:KQ7+USdGKfpPjXk4Ga+5XxQM4Lm4e3gAogrreFAYpOg=
 github.com/mgechev/revive v1.3.3 h1:GUWzV3g185agbHN4ZdaQvR6zrLVYTUSA2ktvIinivK0=
@@ -29,9 +28,6 @@ github.com/pkg/errors v0.9.1 h1:FEBLx1zS214owpjy7qsBeixbURkuhQAwrK5UwLGTwt4=
 github.com/pkg/errors v0.9.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
-github.com/rivo/uniseg v0.2.0/go.mod h1:J6wj4VEh+S6ZtnVlnTBMWIodfgj8LQOQFoIToxlJtxc=
-github.com/rivo/uniseg v0.4.4 h1:8TfxU8dW6PdqD27gjM8MVNuicgxIjxpm4K7x4jp8sis=
-github.com/rivo/uniseg v0.4.4/go.mod h1:FN3SvrM+Zdj16jyLfmOkMNblXMcoc8DfTHruCPUcx88=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/objx v0.4.0/go.mod h1:YvHI0jy2hoMjB+UWwv71VJQ9isScKT/TqJzVSSt89Yw=
 github.com/stretchr/objx v0.5.0/go.mod h1:Yh+to48EsGEfYuaHDzXPcE3xhTkx73EhmCGUpEOglKo=
@@ -41,7 +37,6 @@ github.com/stretchr/testify v1.8.4 h1:CcVxjf3Q8PM0mHUKJCdn+eZZtm5yQwehR5yeSVQQcU
 github.com/stretchr/testify v1.8.4/go.mod h1:sz/lmYIOXD/1dqDmKjjqLyZ2RngseejIcXlSw2iwfAo=
 golang.org/x/mod v0.12.0 h1:rmsUpXtvNzj340zd98LZ4KntptpfRHwpFOHG188oHXc=
 golang.org/x/sys v0.0.0-20220811171246-fbc7d0a398ab/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.6.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.11.0 h1:eG7RXZHdqOJ1i+0lgLgCpSXAp6M3LYlAo6osgSi0xOM=
 golang.org/x/sys v0.11.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/tools v0.12.0 h1:YW6HUoUmYBpwSgyaGaZq1fHjrBjX1rlpZ54T6mu2kss=

parser/parser.go

@@ -1,2 +0,0 @@
-// Package parser implements some common logic of asciigoat based parsers
-package parser

parser/text.go

@@ -1,72 +0,0 @@
-package parser
-
-import (
-	"bytes"
-	"io"
-	"strings"
-
-	"asciigoat.org/core/lexer"
-)
-
-// TextParser ...
-type TextParser struct {
-	src *lexer.Reader
-	pos lexer.Position
-}
-
-// Position ...
-func (p *TextParser) Position() lexer.Position {
-	return p.pos
-}
-
-// StepLine ...
-func (p *TextParser) StepLine() {
-	p.src.Discard()
-	p.pos.StepLine()
-}
-
-// Step ...
-func (p *TextParser) Step() {
-	s := p.src.Emit()
-	p.pos.StepN(len(s))
-}
-
-// Emit ...
-func (p *TextParser) Emit() Token {
-	t := Token{
-		Value:    p.src.Emit(),
-		Position: p.pos,
-	}
-
-	p.pos.StepN(t.Len())
-	return t
-}
-
-// Peek ...
-func (p *TextParser) Peek() string {
-	return p.src.String()
-}
-
-// NewTextParser ...
-func NewTextParser(r io.Reader) *TextParser {
-	if r == nil {
-		r = strings.NewReader("")
-	}
-
-	p := &TextParser{
-		src: lexer.NewReader(r),
-	}
-	p.pos.Reset()
-
-	return p
-}
-
-// NewTextParserBytes ...
-func NewTextParserBytes(b []byte) *TextParser {
-	return NewTextParser(bytes.NewReader(b))
-}
-
-// NewTextParserString ...
-func NewTextParserString(s string) *TextParser {
-	return NewTextParser(strings.NewReader(s))
-}

parser/token.go

@@ -1,31 +0,0 @@
-package parser
-
-import (
-	"fmt"
-
-	"asciigoat.org/core/lexer"
-)
-
-// Token ...
-type Token struct {
-	lexer.Position
-
-	Type  uint
-	Value string
-}
-
-// Len ...
-func (t Token) Len() int {
-	return len(t.Value)
-}
-
-// String generates the '%v' value
-func (t Token) String() string {
-	return t.Value
-}
-
-// GoString generates the '%#v' value
-func (t Token) GoString() string {
-	return fmt.Sprintf("Token{Position{%v,%v}, %v, %q}",
-		t.Line, t.Column, t.Type, t.Value)
-}

reflection/error.go

@@ -1,4 +1,4 @@
-package reflective
+package reflection
 
 import (
 	"bytes"

reflection/reflect_help.go

@@ -0,0 +1,16 @@
+package reflection
+
+import (
+	"fmt"
+	"reflect"
+)
+
+func structFieldName(sf reflect.StructField) string {
+	if sf.Anonymous {
+		idx := sf.Index[len(sf.Index)-1]
+
+		return fmt.Sprintf("%s-%v", "anonymous", idx)
+	}
+
+	return sf.Name
+}

reflection/reflection.go

@@ -0,0 +1,40 @@
+// Package reflection helps Marshalling/Unmarshalling data to structs
+package reflection
+
+import (
+	"reflect"
+)
+
+// Reflection provides Marshalling/Unmarshalling oriented view
+// of a value
+type Reflection struct {
+	v reflect.Value
+
+	types map[reflect.Type]TypeInfo
+}
+
+// Value returns the object it reflects
+func (r *Reflection) Value() any {
+	return r.v.Interface()
+}
+
+// New creates a Reflection of the given pointer
+func New(v any) (*Reflection, error) {
+	rv := reflect.ValueOf(v)
+
+	if rv.Kind() != reflect.Pointer || rv.IsNil() {
+		err := &InvalidUnmarshalError{Type: rv.Type()}
+		return nil, err
+	}
+
+	r := &Reflection{
+		v:     rv,
+		types: make(map[reflect.Type]TypeInfo),
+	}
+
+	if err := r.scan(); err != nil {
+		return nil, err
+	}
+
+	return r, nil
+}

reflection/scan.go

@@ -0,0 +1,37 @@
+package reflection
+
+import (
+	"reflect"
+)
+
+func (r *Reflection) scanType(rt reflect.Type) error {
+	switch rt.Kind() {
+	case reflect.Pointer, reflect.Slice:
+		rt = rt.Elem()
+	}
+
+	if _, ok := r.types[rt]; ok {
+		// cached
+		return nil
+	}
+
+	ti, err := NewTypeInfo(rt)
+	if err != nil {
+		return &UnmarshalTypeError{Type: rt, Err: err}
+	}
+
+	r.types[rt] = ti
+
+	for i := range ti.fields {
+		err := r.scanType(ti.fields[i].sf.Type)
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func (r *Reflection) scan() error {
+	return r.scanType(r.v.Type())
+}

reflection/typeinfo.go

@@ -0,0 +1,108 @@
+package reflection
+
+import (
+	"log"
+	"reflect"
+
+	"github.com/fatih/structtag"
+	"github.com/pkg/errors"
+)
+
+// TypeInfo ...
+type TypeInfo struct {
+	rt reflect.Type
+
+	fields []TypeInfoField
+}
+
+// Type ...
+func (ti *TypeInfo) Type() reflect.Type {
+	return ti.rt
+}
+
+// Kind ...
+func (ti *TypeInfo) Kind() reflect.Kind {
+	return ti.rt.Kind()
+}
+
+// TypeInfoField ...
+type TypeInfoField struct {
+	sf   reflect.StructField
+	tags *structtag.Tags
+
+	Name string
+}
+
+// Type ...
+func (tif *TypeInfoField) Type() reflect.Type {
+	return tif.sf.Type
+}
+
+// Kind ...
+func (tif *TypeInfoField) Kind() reflect.Kind {
+	return tif.sf.Type.Kind()
+}
+
+// Tag ...
+func (tif *TypeInfoField) Tag(key string) (*structtag.Tag, bool) {
+	if tif.tags != nil {
+		tag, _ := tif.tags.Get(key)
+		if tag != nil {
+			return tag, true
+		}
+	}
+	return nil, false
+}
+
+// NewTypeInfo ...
+func NewTypeInfo(rt reflect.Type) (TypeInfo, error) {
+	log.Printf("%s.%s: %s (%s)", "reflection", "NewTypeInfo", rt, rt.Kind())
+
+	ti := TypeInfo{
+		rt: rt,
+	}
+
+	err := ti.init()
+	return ti, err
+}
+
+func (ti *TypeInfo) init() error {
+	switch ti.Kind() {
+	case reflect.Struct:
+		return ti.initStruct()
+	default:
+		return nil
+	}
+}
+
+func (ti *TypeInfo) initStruct() error {
+	// load fields
+	n := ti.rt.NumField()
+	fields := make([]TypeInfoField, 0, n)
+	for i := 0; i < n; i++ {
+		sf := ti.rt.Field(i)
+		tags, err := structtag.Parse(string(sf.Tag))
+
+		if err != nil {
+			// tag parse error
+			err = &UnmarshalTypeError{
+				Type: ti.rt,
+				Err:  errors.Wrap(err, structFieldName(sf)),
+			}
+			return err
+		}
+
+		if sf.IsExported() {
+			log.Printf("%s.%s:   [%v]: %q %s (%s)",
+				"reflection", "NewTypeInfo",
+				i, structFieldName(sf), sf.Type, sf.Type.Kind())
+
+			fields = append(fields, TypeInfoField{
+				sf:   sf,
+				tags: tags,
+			})
+		}
+	}
+	ti.fields = fields
+	return nil
+}

reflective/docs.go

@@ -1,2 +0,0 @@
-// Package reflective assists reflection-driven unmarshalling
-package reflective

reflective/helpers.go

@@ -1,15 +0,0 @@
-package reflective
-
-import "reflect"
-
-// IsZero tells if a value is zero either via
-// v.IsZero() or reflection.
-func IsZero(iv any) bool {
-	if p, ok := iv.(interface {
-		IsZero() bool
-	}); ok {
-		return p.IsZero()
-	}
-
-	return reflect.ValueOf(iv).IsZero()
-}

reflective/reflection.go

@@ -1,27 +0,0 @@
-package reflective
-
-import "reflect"
-
-// Reflection provides Marshalling/Unmarshalling oriented view
-// of a value
-type Reflection struct {
-	v reflect.Value
-}
-
-// New creates a Reflection of the given pointer
-func New(v any) (*Reflection, error) {
-	rv := reflect.ValueOf(v)
-
-	if rv.Kind() != reflect.Pointer || rv.IsNil() {
-		err := &InvalidUnmarshalError{
-			Type: rv.Type(),
-		}
-		return nil, err
-	}
-
-	r := &Reflection{
-		v: rv,
-	}
-
-	return r, nil
-}