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feat: support get filed value
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Change-Id: I450040c01436fc42143a3cca88348be082f60ab1
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@andeya
andeya committed Feb 3, 2019
1 parent b80b3a3 commit 925df37
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Showing 4 changed files with 137 additions and 55 deletions.
8 changes: 7 additions & 1 deletion README.md
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Expand Up @@ -154,7 +154,13 @@ Operator priority(high -> low):
* `&&`
* `||`

## Selector
## Field Selector

```
field_lv1.field_lv2...field_lvn
```

## Expression Selector

If expression is **multiple model** and exprName is not `@`:

Expand Down
8 changes: 4 additions & 4 deletions expr_test.go
View file
Expand Up @@ -126,7 +126,7 @@ func TestExpr(t *testing.T) {
if f, ok := c.val.(float64); ok && math.IsNaN(f) && math.IsNaN(val.(float64)) {
continue
}
t.Fatalf("expr: %q, got: %v, want: %v", c.expr, val, c.val)
t.Fatalf("expr: %q, got: %v, expect: %v", c.expr, val, c.val)
}
}
}
Expand Down Expand Up @@ -154,7 +154,7 @@ func TestPriority(t *testing.T) {
if f, ok := c.val.(float64); ok && math.IsNaN(f) && math.IsNaN(val.(float64)) {
continue
}
t.Fatalf("expr: %q, got: %v, want: %v", c.expr, val, c.val)
t.Fatalf("expr: %q, got: %v, expect: %v", c.expr, val, c.val)
}
}
}
Expand Down Expand Up @@ -190,7 +190,7 @@ func TestBuiltInFunc(t *testing.T) {
if f, ok := c.val.(float64); ok && math.IsNaN(f) && math.IsNaN(val.(float64)) {
continue
}
t.Fatalf("expr: %q, got: %v, want: %v", c.expr, val, c.val)
t.Fatalf("expr: %q, got: %v, expect: %v", c.expr, val, c.val)
}
}
}
Expand All @@ -212,7 +212,7 @@ func TestSyntaxIncorrect(t *testing.T) {
for _, c := range cases {
_, err := parseExpr(c.incorrectExpr)
if err == nil {
t.Fatalf("want syntax incorrect: %s", c.incorrectExpr)
t.Fatalf("expect syntax incorrect: %s", c.incorrectExpr)
} else {
t.Log(err)
}
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95 changes: 52 additions & 43 deletions tagexpr.go
View file
Expand Up @@ -27,31 +27,31 @@ import (
// VM struct tag expression interpreter
type VM struct {
tagName string
structJar map[string]*Struct
structJar map[string]*structVM
rw sync.RWMutex
}

// Struct tag expression set of struct
type Struct struct {
// structVM tag expression set of struct
type structVM struct {
vm *VM
name string
fields map[string]*Field
fields map[string]*fieldVM
exprs map[string]*Expr
selectorList []string
}

// Field tag expression set of struct field
type Field struct {
// fieldVM tag expression set of struct field
type fieldVM struct {
reflect.StructField
host *Struct
host *structVM
valueGetter func(uintptr) interface{}
}

// New creates a tag expression interpreter that uses @tagName as the tag name.
func New(tagName string) *VM {
return &VM{
tagName: tagName,
structJar: make(map[string]*Struct, 256),
structJar: make(map[string]*structVM, 256),
}
}

Expand Down Expand Up @@ -109,7 +109,7 @@ func (vm *VM) Run(structPtr interface{}) (*TagExpr, error) {
return s.newTagExpr(v.Pointer()), nil
}

func (vm *VM) registerStructLocked(structType reflect.Type) (*Struct, error) {
func (vm *VM) registerStructLocked(structType reflect.Type) (*structVM, error) {
structType, err := vm.getStructType(structType)
if err != nil {
return nil, err
Expand All @@ -119,14 +119,14 @@ func (vm *VM) registerStructLocked(structType reflect.Type) (*Struct, error) {
if had {
return s, nil
}
s = vm.newStruct()
s = vm.newStructVM()
vm.structJar[structTypeName] = s
var numField = structType.NumField()
var structField reflect.StructField
var sub *Struct
var sub *structVM
for i := 0; i < numField; i++ {
structField = structType.Field(i)
field, err := s.newField(structField)
field, err := s.newFieldVM(structField)
if err != nil {
return nil, err
}
Expand Down Expand Up @@ -160,17 +160,17 @@ func (vm *VM) registerStructLocked(structType reflect.Type) (*Struct, error) {
return s, nil
}

func (vm *VM) newStruct() *Struct {
return &Struct{
func (vm *VM) newStructVM() *structVM {
return &structVM{
vm: vm,
fields: make(map[string]*Field, 16),
fields: make(map[string]*fieldVM, 16),
exprs: make(map[string]*Expr, 64),
selectorList: make([]string, 0, 64),
}
}

func (s *Struct) newField(structField reflect.StructField) (*Field, error) {
f := &Field{
func (s *structVM) newFieldVM(structField reflect.StructField) (*fieldVM, error) {
f := &fieldVM{
StructField: structField,
host: s,
}
Expand All @@ -182,15 +182,15 @@ func (s *Struct) newField(structField reflect.StructField) (*Field, error) {
return f, nil
}

func (f *Field) newFrom(ptr uintptr, ptrDeep int) reflect.Value {
func (f *fieldVM) newFrom(ptr uintptr, ptrDeep int) reflect.Value {
v := reflect.NewAt(f.Type, unsafe.Pointer(ptr+f.Offset)).Elem()
for i := 0; i < ptrDeep; i++ {
v = v.Elem()
}
return v
}

func (f *Field) setFloatGetter(kind reflect.Kind, ptrDeep int) {
func (f *fieldVM) setFloatGetter(kind reflect.Kind, ptrDeep int) {
if ptrDeep == 0 {
f.valueGetter = func(ptr uintptr) interface{} {
return getFloat64(kind, ptr+f.Offset)
Expand All @@ -206,7 +206,7 @@ func (f *Field) setFloatGetter(kind reflect.Kind, ptrDeep int) {
}
}

func (f *Field) setBoolGetter(ptrDeep int) {
func (f *fieldVM) setBoolGetter(ptrDeep int) {
if ptrDeep == 0 {
f.valueGetter = func(ptr uintptr) interface{} {
return *(*bool)(unsafe.Pointer(ptr + f.Offset))
Expand All @@ -222,7 +222,7 @@ func (f *Field) setBoolGetter(ptrDeep int) {
}
}

func (f *Field) setStringGetter(ptrDeep int) {
func (f *fieldVM) setStringGetter(ptrDeep int) {
if ptrDeep == 0 {
f.valueGetter = func(ptr uintptr) interface{} {
return *(*string)(unsafe.Pointer(ptr + f.Offset))
Expand All @@ -238,13 +238,13 @@ func (f *Field) setStringGetter(ptrDeep int) {
}
}

func (f *Field) setLengthGetter(ptrDeep int) {
func (f *fieldVM) setLengthGetter(ptrDeep int) {
f.valueGetter = func(ptr uintptr) interface{} {
return f.newFrom(ptr, ptrDeep).Interface()
}
}

func (f *Field) parseExprs(tag string) error {
func (f *fieldVM) parseExprs(tag string) error {
raw := tag
tag = strings.TrimSpace(tag)
if tag == "" {
Expand Down Expand Up @@ -300,11 +300,11 @@ func (f *Field) parseExprs(tag string) error {
}
}

func (s *Struct) copySubFields(field *Field, sub *Struct, ptrDeep int) {
func (s *structVM) copySubFields(field *fieldVM, sub *structVM, ptrDeep int) {
nameSpace := field.Name
for k, v := range sub.fields {
valueGetter := v.valueGetter
f := &Field{
f := &fieldVM{
StructField: v.StructField,
host: v.host,
}
Expand All @@ -315,11 +315,11 @@ func (s *Struct) copySubFields(field *Field, sub *Struct, ptrDeep int) {
}
} else {
f.valueGetter = func(ptr uintptr) interface{} {
newField := reflect.NewAt(field.Type, unsafe.Pointer(ptr+field.Offset))
newFieldVM := reflect.NewAt(field.Type, unsafe.Pointer(ptr+field.Offset))
for i := 0; i < ptrDeep; i++ {
newField = newField.Elem()
newFieldVM = newFieldVM.Elem()
}
return valueGetter(uintptr(newField.Pointer()))
return valueGetter(uintptr(newFieldVM.Pointer()))
}
}
}
Expand All @@ -344,7 +344,7 @@ func (vm *VM) getStructType(t reflect.Type) (reflect.Type, error) {
return structType, nil
}

func (s *Struct) newTagExpr(ptr uintptr) *TagExpr {
func (s *structVM) newTagExpr(ptr uintptr) *TagExpr {
te := &TagExpr{
s: s,
ptr: ptr,
Expand All @@ -354,60 +354,69 @@ func (s *Struct) newTagExpr(ptr uintptr) *TagExpr {

// TagExpr struct tag expression evaluator
type TagExpr struct {
s *Struct
s *structVM
ptr uintptr
}

// EvalFloat evaluate the value of the struct tag expression by the selector expression.
// NOTE:
// If the expression value type is not float64, return 0.
func (t *TagExpr) EvalFloat(selector string) float64 {
r, _ := t.Eval(selector).(float64)
func (t *TagExpr) EvalFloat(exprSelector string) float64 {
r, _ := t.Eval(exprSelector).(float64)
return r
}

// EvalString evaluate the value of the struct tag expression by the selector expression.
// NOTE:
// If the expression value type is not string, return "".
func (t *TagExpr) EvalString(selector string) string {
r, _ := t.Eval(selector).(string)
func (t *TagExpr) EvalString(exprSelector string) string {
r, _ := t.Eval(exprSelector).(string)
return r
}

// EvalBool evaluate the value of the struct tag expression by the selector expression.
// NOTE:
// If the expression value type is not bool, return false.
func (t *TagExpr) EvalBool(selector string) bool {
r, _ := t.Eval(selector).(bool)
func (t *TagExpr) EvalBool(exprSelector string) bool {
r, _ := t.Eval(exprSelector).(bool)
return r
}

// Eval evaluate the value of the struct tag expression by the selector expression.
// NOTE:
// format: fieldName, fieldName.exprName, fieldName1.fieldName2.exprName1
// result types: float64, string, bool, nil
func (t *TagExpr) Eval(selector string) interface{} {
expr, ok := t.s.exprs[selector]
func (t *TagExpr) Eval(exprSelector string) interface{} {
expr, ok := t.s.exprs[exprSelector]
if !ok {
return nil
}
return expr.run(getFieldSelector(selector), t)
return expr.run(getFieldSelector(exprSelector), t)
}

// Range loop through each tag expression
// NOTE:
// eval result types: float64, string, bool, nil
func (t *TagExpr) Range(fn func(selector string, eval func() interface{}) bool) {
func (t *TagExpr) Range(fn func(exprSelector string, eval func() interface{}) bool) {
exprs := t.s.exprs
for _, selector := range t.s.selectorList {
if !fn(selector, func() interface{} {
return exprs[selector].run(getFieldSelector(selector), t)
for _, exprSelector := range t.s.selectorList {
if !fn(exprSelector, func() interface{} {
return exprs[exprSelector].run(getFieldSelector(exprSelector), t)
}) {
return
}
}
}

// Field returns the field reflect.Value specified by the selector.
func (t *TagExpr) Field(fieldSelector string) reflect.Value {
f, ok := t.s.fields[fieldSelector]
if !ok {
return reflect.Value{}
}
return reflect.NewAt(f.Type, unsafe.Pointer(t.ptr+f.Offset)).Elem()
}

func (t *TagExpr) getValue(field string, subFields []interface{}) (v interface{}) {
f, ok := t.s.fields[field]
if !ok {
Expand Down

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