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path: root/vendor/github.com/BurntSushi/toml/decode.go
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-rw-r--r--vendor/github.com/BurntSushi/toml/decode.go613
1 files changed, 613 insertions, 0 deletions
diff --git a/vendor/github.com/BurntSushi/toml/decode.go b/vendor/github.com/BurntSushi/toml/decode.go
new file mode 100644
index 0000000..7aaf462
--- /dev/null
+++ b/vendor/github.com/BurntSushi/toml/decode.go
@@ -0,0 +1,613 @@
+package toml
+
+import (
+ "bytes"
+ "encoding"
+ "encoding/json"
+ "fmt"
+ "io"
+ "io/fs"
+ "math"
+ "os"
+ "reflect"
+ "strconv"
+ "strings"
+ "time"
+)
+
+// Unmarshaler is the interface implemented by objects that can unmarshal a
+// TOML description of themselves.
+type Unmarshaler interface {
+ UnmarshalTOML(any) error
+}
+
+// Unmarshal decodes the contents of data in TOML format into a pointer v.
+//
+// See [Decoder] for a description of the decoding process.
+func Unmarshal(data []byte, v any) error {
+ _, err := NewDecoder(bytes.NewReader(data)).Decode(v)
+ return err
+}
+
+// Decode the TOML data in to the pointer v.
+//
+// See [Decoder] for a description of the decoding process.
+func Decode(data string, v any) (MetaData, error) {
+ return NewDecoder(strings.NewReader(data)).Decode(v)
+}
+
+// DecodeFile reads the contents of a file and decodes it with [Decode].
+func DecodeFile(path string, v any) (MetaData, error) {
+ fp, err := os.Open(path)
+ if err != nil {
+ return MetaData{}, err
+ }
+ defer fp.Close()
+ return NewDecoder(fp).Decode(v)
+}
+
+// DecodeFS reads the contents of a file from [fs.FS] and decodes it with
+// [Decode].
+func DecodeFS(fsys fs.FS, path string, v any) (MetaData, error) {
+ fp, err := fsys.Open(path)
+ if err != nil {
+ return MetaData{}, err
+ }
+ defer fp.Close()
+ return NewDecoder(fp).Decode(v)
+}
+
+// Primitive is a TOML value that hasn't been decoded into a Go value.
+//
+// This type can be used for any value, which will cause decoding to be delayed.
+// You can use [PrimitiveDecode] to "manually" decode these values.
+//
+// NOTE: The underlying representation of a `Primitive` value is subject to
+// change. Do not rely on it.
+//
+// NOTE: Primitive values are still parsed, so using them will only avoid the
+// overhead of reflection. They can be useful when you don't know the exact type
+// of TOML data until runtime.
+type Primitive struct {
+ undecoded any
+ context Key
+}
+
+// The significand precision for float32 and float64 is 24 and 53 bits; this is
+// the range a natural number can be stored in a float without loss of data.
+const (
+ maxSafeFloat32Int = 16777215 // 2^24-1
+ maxSafeFloat64Int = int64(9007199254740991) // 2^53-1
+)
+
+// Decoder decodes TOML data.
+//
+// TOML tables correspond to Go structs or maps; they can be used
+// interchangeably, but structs offer better type safety.
+//
+// TOML table arrays correspond to either a slice of structs or a slice of maps.
+//
+// TOML datetimes correspond to [time.Time]. Local datetimes are parsed in the
+// local timezone.
+//
+// [time.Duration] types are treated as nanoseconds if the TOML value is an
+// integer, or they're parsed with time.ParseDuration() if they're strings.
+//
+// All other TOML types (float, string, int, bool and array) correspond to the
+// obvious Go types.
+//
+// An exception to the above rules is if a type implements the TextUnmarshaler
+// interface, in which case any primitive TOML value (floats, strings, integers,
+// booleans, datetimes) will be converted to a []byte and given to the value's
+// UnmarshalText method. See the Unmarshaler example for a demonstration with
+// email addresses.
+//
+// # Key mapping
+//
+// TOML keys can map to either keys in a Go map or field names in a Go struct.
+// The special `toml` struct tag can be used to map TOML keys to struct fields
+// that don't match the key name exactly (see the example). A case insensitive
+// match to struct names will be tried if an exact match can't be found.
+//
+// The mapping between TOML values and Go values is loose. That is, there may
+// exist TOML values that cannot be placed into your representation, and there
+// may be parts of your representation that do not correspond to TOML values.
+// This loose mapping can be made stricter by using the IsDefined and/or
+// Undecoded methods on the MetaData returned.
+//
+// This decoder does not handle cyclic types. Decode will not terminate if a
+// cyclic type is passed.
+type Decoder struct {
+ r io.Reader
+}
+
+// NewDecoder creates a new Decoder.
+func NewDecoder(r io.Reader) *Decoder {
+ return &Decoder{r: r}
+}
+
+var (
+ unmarshalToml = reflect.TypeOf((*Unmarshaler)(nil)).Elem()
+ unmarshalText = reflect.TypeOf((*encoding.TextUnmarshaler)(nil)).Elem()
+ primitiveType = reflect.TypeOf((*Primitive)(nil)).Elem()
+)
+
+// Decode TOML data in to the pointer `v`.
+func (dec *Decoder) Decode(v any) (MetaData, error) {
+ rv := reflect.ValueOf(v)
+ if rv.Kind() != reflect.Ptr {
+ s := "%q"
+ if reflect.TypeOf(v) == nil {
+ s = "%v"
+ }
+
+ return MetaData{}, fmt.Errorf("toml: cannot decode to non-pointer "+s, reflect.TypeOf(v))
+ }
+ if rv.IsNil() {
+ return MetaData{}, fmt.Errorf("toml: cannot decode to nil value of %q", reflect.TypeOf(v))
+ }
+
+ // Check if this is a supported type: struct, map, any, or something that
+ // implements UnmarshalTOML or UnmarshalText.
+ rv = indirect(rv)
+ rt := rv.Type()
+ if rv.Kind() != reflect.Struct && rv.Kind() != reflect.Map &&
+ !(rv.Kind() == reflect.Interface && rv.NumMethod() == 0) &&
+ !rt.Implements(unmarshalToml) && !rt.Implements(unmarshalText) {
+ return MetaData{}, fmt.Errorf("toml: cannot decode to type %s", rt)
+ }
+
+ // TODO: parser should read from io.Reader? Or at the very least, make it
+ // read from []byte rather than string
+ data, err := io.ReadAll(dec.r)
+ if err != nil {
+ return MetaData{}, err
+ }
+
+ p, err := parse(string(data))
+ if err != nil {
+ return MetaData{}, err
+ }
+
+ md := MetaData{
+ mapping: p.mapping,
+ keyInfo: p.keyInfo,
+ keys: p.ordered,
+ decoded: make(map[string]struct{}, len(p.ordered)),
+ context: nil,
+ data: data,
+ }
+ return md, md.unify(p.mapping, rv)
+}
+
+// PrimitiveDecode is just like the other Decode* functions, except it decodes a
+// TOML value that has already been parsed. Valid primitive values can *only* be
+// obtained from values filled by the decoder functions, including this method.
+// (i.e., v may contain more [Primitive] values.)
+//
+// Meta data for primitive values is included in the meta data returned by the
+// Decode* functions with one exception: keys returned by the Undecoded method
+// will only reflect keys that were decoded. Namely, any keys hidden behind a
+// Primitive will be considered undecoded. Executing this method will update the
+// undecoded keys in the meta data. (See the example.)
+func (md *MetaData) PrimitiveDecode(primValue Primitive, v any) error {
+ md.context = primValue.context
+ defer func() { md.context = nil }()
+ return md.unify(primValue.undecoded, rvalue(v))
+}
+
+// unify performs a sort of type unification based on the structure of `rv`,
+// which is the client representation.
+//
+// Any type mismatch produces an error. Finding a type that we don't know
+// how to handle produces an unsupported type error.
+func (md *MetaData) unify(data any, rv reflect.Value) error {
+ // Special case. Look for a `Primitive` value.
+ // TODO: #76 would make this superfluous after implemented.
+ if rv.Type() == primitiveType {
+ // Save the undecoded data and the key context into the primitive
+ // value.
+ context := make(Key, len(md.context))
+ copy(context, md.context)
+ rv.Set(reflect.ValueOf(Primitive{
+ undecoded: data,
+ context: context,
+ }))
+ return nil
+ }
+
+ rvi := rv.Interface()
+ if v, ok := rvi.(Unmarshaler); ok {
+ err := v.UnmarshalTOML(data)
+ if err != nil {
+ return md.parseErr(err)
+ }
+ return nil
+ }
+ if v, ok := rvi.(encoding.TextUnmarshaler); ok {
+ return md.unifyText(data, v)
+ }
+
+ // TODO:
+ // The behavior here is incorrect whenever a Go type satisfies the
+ // encoding.TextUnmarshaler interface but also corresponds to a TOML hash or
+ // array. In particular, the unmarshaler should only be applied to primitive
+ // TOML values. But at this point, it will be applied to all kinds of values
+ // and produce an incorrect error whenever those values are hashes or arrays
+ // (including arrays of tables).
+
+ k := rv.Kind()
+
+ if k >= reflect.Int && k <= reflect.Uint64 {
+ return md.unifyInt(data, rv)
+ }
+ switch k {
+ case reflect.Struct:
+ return md.unifyStruct(data, rv)
+ case reflect.Map:
+ return md.unifyMap(data, rv)
+ case reflect.Array:
+ return md.unifyArray(data, rv)
+ case reflect.Slice:
+ return md.unifySlice(data, rv)
+ case reflect.String:
+ return md.unifyString(data, rv)
+ case reflect.Bool:
+ return md.unifyBool(data, rv)
+ case reflect.Interface:
+ if rv.NumMethod() > 0 { /// Only empty interfaces are supported.
+ return md.e("unsupported type %s", rv.Type())
+ }
+ return md.unifyAnything(data, rv)
+ case reflect.Float32, reflect.Float64:
+ return md.unifyFloat64(data, rv)
+ }
+ return md.e("unsupported type %s", rv.Kind())
+}
+
+func (md *MetaData) unifyStruct(mapping any, rv reflect.Value) error {
+ tmap, ok := mapping.(map[string]any)
+ if !ok {
+ if mapping == nil {
+ return nil
+ }
+ return md.e("type mismatch for %s: expected table but found %s", rv.Type().String(), fmtType(mapping))
+ }
+
+ for key, datum := range tmap {
+ var f *field
+ fields := cachedTypeFields(rv.Type())
+ for i := range fields {
+ ff := &fields[i]
+ if ff.name == key {
+ f = ff
+ break
+ }
+ if f == nil && strings.EqualFold(ff.name, key) {
+ f = ff
+ }
+ }
+ if f != nil {
+ subv := rv
+ for _, i := range f.index {
+ subv = indirect(subv.Field(i))
+ }
+
+ if isUnifiable(subv) {
+ md.decoded[md.context.add(key).String()] = struct{}{}
+ md.context = append(md.context, key)
+
+ err := md.unify(datum, subv)
+ if err != nil {
+ return err
+ }
+ md.context = md.context[0 : len(md.context)-1]
+ } else if f.name != "" {
+ return md.e("cannot write unexported field %s.%s", rv.Type().String(), f.name)
+ }
+ }
+ }
+ return nil
+}
+
+func (md *MetaData) unifyMap(mapping any, rv reflect.Value) error {
+ keyType := rv.Type().Key().Kind()
+ if keyType != reflect.String && keyType != reflect.Interface {
+ return fmt.Errorf("toml: cannot decode to a map with non-string key type (%s in %q)",
+ keyType, rv.Type())
+ }
+
+ tmap, ok := mapping.(map[string]any)
+ if !ok {
+ if tmap == nil {
+ return nil
+ }
+ return md.badtype("map", mapping)
+ }
+ if rv.IsNil() {
+ rv.Set(reflect.MakeMap(rv.Type()))
+ }
+ for k, v := range tmap {
+ md.decoded[md.context.add(k).String()] = struct{}{}
+ md.context = append(md.context, k)
+
+ rvval := reflect.Indirect(reflect.New(rv.Type().Elem()))
+
+ err := md.unify(v, indirect(rvval))
+ if err != nil {
+ return err
+ }
+ md.context = md.context[0 : len(md.context)-1]
+
+ rvkey := indirect(reflect.New(rv.Type().Key()))
+
+ switch keyType {
+ case reflect.Interface:
+ rvkey.Set(reflect.ValueOf(k))
+ case reflect.String:
+ rvkey.SetString(k)
+ }
+
+ rv.SetMapIndex(rvkey, rvval)
+ }
+ return nil
+}
+
+func (md *MetaData) unifyArray(data any, rv reflect.Value) error {
+ datav := reflect.ValueOf(data)
+ if datav.Kind() != reflect.Slice {
+ if !datav.IsValid() {
+ return nil
+ }
+ return md.badtype("slice", data)
+ }
+ if l := datav.Len(); l != rv.Len() {
+ return md.e("expected array length %d; got TOML array of length %d", rv.Len(), l)
+ }
+ return md.unifySliceArray(datav, rv)
+}
+
+func (md *MetaData) unifySlice(data any, rv reflect.Value) error {
+ datav := reflect.ValueOf(data)
+ if datav.Kind() != reflect.Slice {
+ if !datav.IsValid() {
+ return nil
+ }
+ return md.badtype("slice", data)
+ }
+ n := datav.Len()
+ if rv.IsNil() || rv.Cap() < n {
+ rv.Set(reflect.MakeSlice(rv.Type(), n, n))
+ }
+ rv.SetLen(n)
+ return md.unifySliceArray(datav, rv)
+}
+
+func (md *MetaData) unifySliceArray(data, rv reflect.Value) error {
+ l := data.Len()
+ for i := 0; i < l; i++ {
+ err := md.unify(data.Index(i).Interface(), indirect(rv.Index(i)))
+ if err != nil {
+ return err
+ }
+ }
+ return nil
+}
+
+func (md *MetaData) unifyString(data any, rv reflect.Value) error {
+ _, ok := rv.Interface().(json.Number)
+ if ok {
+ if i, ok := data.(int64); ok {
+ rv.SetString(strconv.FormatInt(i, 10))
+ } else if f, ok := data.(float64); ok {
+ rv.SetString(strconv.FormatFloat(f, 'f', -1, 64))
+ } else {
+ return md.badtype("string", data)
+ }
+ return nil
+ }
+
+ if s, ok := data.(string); ok {
+ rv.SetString(s)
+ return nil
+ }
+ return md.badtype("string", data)
+}
+
+func (md *MetaData) unifyFloat64(data any, rv reflect.Value) error {
+ rvk := rv.Kind()
+
+ if num, ok := data.(float64); ok {
+ switch rvk {
+ case reflect.Float32:
+ if num < -math.MaxFloat32 || num > math.MaxFloat32 {
+ return md.parseErr(errParseRange{i: num, size: rvk.String()})
+ }
+ fallthrough
+ case reflect.Float64:
+ rv.SetFloat(num)
+ default:
+ panic("bug")
+ }
+ return nil
+ }
+
+ if num, ok := data.(int64); ok {
+ if (rvk == reflect.Float32 && (num < -maxSafeFloat32Int || num > maxSafeFloat32Int)) ||
+ (rvk == reflect.Float64 && (num < -maxSafeFloat64Int || num > maxSafeFloat64Int)) {
+ return md.parseErr(errUnsafeFloat{i: num, size: rvk.String()})
+ }
+ rv.SetFloat(float64(num))
+ return nil
+ }
+
+ return md.badtype("float", data)
+}
+
+func (md *MetaData) unifyInt(data any, rv reflect.Value) error {
+ _, ok := rv.Interface().(time.Duration)
+ if ok {
+ // Parse as string duration, and fall back to regular integer parsing
+ // (as nanosecond) if this is not a string.
+ if s, ok := data.(string); ok {
+ dur, err := time.ParseDuration(s)
+ if err != nil {
+ return md.parseErr(errParseDuration{s})
+ }
+ rv.SetInt(int64(dur))
+ return nil
+ }
+ }
+
+ num, ok := data.(int64)
+ if !ok {
+ return md.badtype("integer", data)
+ }
+
+ rvk := rv.Kind()
+ switch {
+ case rvk >= reflect.Int && rvk <= reflect.Int64:
+ if (rvk == reflect.Int8 && (num < math.MinInt8 || num > math.MaxInt8)) ||
+ (rvk == reflect.Int16 && (num < math.MinInt16 || num > math.MaxInt16)) ||
+ (rvk == reflect.Int32 && (num < math.MinInt32 || num > math.MaxInt32)) {
+ return md.parseErr(errParseRange{i: num, size: rvk.String()})
+ }
+ rv.SetInt(num)
+ case rvk >= reflect.Uint && rvk <= reflect.Uint64:
+ unum := uint64(num)
+ if rvk == reflect.Uint8 && (num < 0 || unum > math.MaxUint8) ||
+ rvk == reflect.Uint16 && (num < 0 || unum > math.MaxUint16) ||
+ rvk == reflect.Uint32 && (num < 0 || unum > math.MaxUint32) {
+ return md.parseErr(errParseRange{i: num, size: rvk.String()})
+ }
+ rv.SetUint(unum)
+ default:
+ panic("unreachable")
+ }
+ return nil
+}
+
+func (md *MetaData) unifyBool(data any, rv reflect.Value) error {
+ if b, ok := data.(bool); ok {
+ rv.SetBool(b)
+ return nil
+ }
+ return md.badtype("boolean", data)
+}
+
+func (md *MetaData) unifyAnything(data any, rv reflect.Value) error {
+ rv.Set(reflect.ValueOf(data))
+ return nil
+}
+
+func (md *MetaData) unifyText(data any, v encoding.TextUnmarshaler) error {
+ var s string
+ switch sdata := data.(type) {
+ case Marshaler:
+ text, err := sdata.MarshalTOML()
+ if err != nil {
+ return err
+ }
+ s = string(text)
+ case encoding.TextMarshaler:
+ text, err := sdata.MarshalText()
+ if err != nil {
+ return err
+ }
+ s = string(text)
+ case fmt.Stringer:
+ s = sdata.String()
+ case string:
+ s = sdata
+ case bool:
+ s = fmt.Sprintf("%v", sdata)
+ case int64:
+ s = fmt.Sprintf("%d", sdata)
+ case float64:
+ s = fmt.Sprintf("%f", sdata)
+ default:
+ return md.badtype("primitive (string-like)", data)
+ }
+ if err := v.UnmarshalText([]byte(s)); err != nil {
+ return md.parseErr(err)
+ }
+ return nil
+}
+
+func (md *MetaData) badtype(dst string, data any) error {
+ return md.e("incompatible types: TOML value has type %s; destination has type %s", fmtType(data), dst)
+}
+
+func (md *MetaData) parseErr(err error) error {
+ k := md.context.String()
+ return ParseError{
+ LastKey: k,
+ Position: md.keyInfo[k].pos,
+ Line: md.keyInfo[k].pos.Line,
+ err: err,
+ input: string(md.data),
+ }
+}
+
+func (md *MetaData) e(format string, args ...any) error {
+ f := "toml: "
+ if len(md.context) > 0 {
+ f = fmt.Sprintf("toml: (last key %q): ", md.context)
+ p := md.keyInfo[md.context.String()].pos
+ if p.Line > 0 {
+ f = fmt.Sprintf("toml: line %d (last key %q): ", p.Line, md.context)
+ }
+ }
+ return fmt.Errorf(f+format, args...)
+}
+
+// rvalue returns a reflect.Value of `v`. All pointers are resolved.
+func rvalue(v any) reflect.Value {
+ return indirect(reflect.ValueOf(v))
+}
+
+// indirect returns the value pointed to by a pointer.
+//
+// Pointers are followed until the value is not a pointer. New values are
+// allocated for each nil pointer.
+//
+// An exception to this rule is if the value satisfies an interface of interest
+// to us (like encoding.TextUnmarshaler).
+func indirect(v reflect.Value) reflect.Value {
+ if v.Kind() != reflect.Ptr {
+ if v.CanSet() {
+ pv := v.Addr()
+ pvi := pv.Interface()
+ if _, ok := pvi.(encoding.TextUnmarshaler); ok {
+ return pv
+ }
+ if _, ok := pvi.(Unmarshaler); ok {
+ return pv
+ }
+ }
+ return v
+ }
+ if v.IsNil() {
+ v.Set(reflect.New(v.Type().Elem()))
+ }
+ return indirect(reflect.Indirect(v))
+}
+
+func isUnifiable(rv reflect.Value) bool {
+ if rv.CanSet() {
+ return true
+ }
+ rvi := rv.Interface()
+ if _, ok := rvi.(encoding.TextUnmarshaler); ok {
+ return true
+ }
+ if _, ok := rvi.(Unmarshaler); ok {
+ return true
+ }
+ return false
+}
+
+// fmt %T with "interface {}" replaced with "any", which is far more readable.
+func fmtType(t any) string {
+ return strings.ReplaceAll(fmt.Sprintf("%T", t), "interface {}", "any")
+}