add vendor data

vendor/github.com/dunglas/httpsfv/params.go

@@ -0,0 +1,143 @@
+package httpsfv
+
+import (
+	"errors"
+	"strings"
+)
+
+// Params are an ordered map of key-value pairs that are associated with an item or an inner list.
+//
+// See https://httpwg.org/specs/rfc9651.html#param.
+type Params struct {
+	names  []string
+	values map[string]interface{}
+}
+
+// ErrInvalidParameterFormat is returned when the format of a parameter is invalid.
+var ErrInvalidParameterFormat = errors.New("invalid parameter format")
+
+// ErrInvalidParameterValue is returned when a parameter key is invalid.
+var ErrInvalidParameterValue = errors.New("invalid parameter value")
+
+// ErrMissingParameters is returned when the Params structure is missing from the element.
+var ErrMissingParameters = errors.New("missing parameters")
+
+// NewParams creates a new ordered map.
+func NewParams() *Params {
+	p := Params{}
+	p.names = []string{}
+	p.values = map[string]interface{}{}
+
+	return &p
+}
+
+// Get retrieves a parameter.
+func (p *Params) Get(k string) (interface{}, bool) {
+	v, ok := p.values[k]
+
+	return v, ok
+}
+
+// Add appends a new parameter to the ordered list.
+// If the key already exists, overwrite its value.
+func (p *Params) Add(k string, v interface{}) {
+	assertBareItem(v)
+
+	if _, exists := p.values[k]; !exists {
+		p.names = append(p.names, k)
+	}
+
+	p.values[k] = v
+}
+
+// Del removes a parameter from the ordered list.
+func (p *Params) Del(key string) bool {
+	if _, ok := p.values[key]; !ok {
+		return false
+	}
+
+	for i, k := range p.names {
+		if k == key {
+			p.names = append(p.names[:i], p.names[i+1:]...)
+
+			break
+		}
+	}
+
+	delete(p.values, key)
+
+	return true
+}
+
+// Names retrieves the list of parameter names in the appropriate order.
+func (p *Params) Names() []string {
+	return p.names
+}
+
+// marshalSFV serializes as defined in
+// https://httpwg.org/specs/rfc9651.html#ser-params.
+func (p *Params) marshalSFV(b *strings.Builder) error {
+	if p == nil {
+		return ErrMissingParameters
+	}
+	for _, k := range p.names {
+		if err := b.WriteByte(';'); err != nil {
+			return err
+		}
+
+		if err := marshalKey(b, k); err != nil {
+			return err
+		}
+
+		v := p.values[k]
+		if v == true {
+			continue
+		}
+
+		if err := b.WriteByte('='); err != nil {
+			return err
+		}
+
+		if err := marshalBareItem(b, v); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+// parseParams parses as defined in
+// https://httpwg.org/specs/rfc9651.html#parse-param.
+func parseParams(s *scanner) (*Params, error) {
+	p := NewParams()
+
+	for !s.eof() {
+		if s.data[s.off] != ';' {
+			break
+		}
+		s.off++
+		s.scanWhileSp()
+
+		k, err := parseKey(s)
+		if err != nil {
+			return nil, err
+		}
+
+		var i interface{}
+
+		if !s.eof() && s.data[s.off] == '=' {
+			s.off++
+
+			i, err = parseBareItem(s)
+			if err != nil {
+				return nil, err
+			}
+		} else {
+			i = true
+		}
+
+		p.Add(k, i)
+	}
+
+	return p, nil
+}