Implement webhook branch filter (#7791)

* Fix validate() function to handle errors in embedded anon structs

* Implement webhook branch filter

See #2025, #3998.

vendor/github.com/gobwas/glob/syntax/ast/parser.go

@@ -0,0 +1,157 @@
+package ast
+
+import (
+	"errors"
+	"fmt"
+	"github.com/gobwas/glob/syntax/lexer"
+	"unicode/utf8"
+)
+
+type Lexer interface {
+	Next() lexer.Token
+}
+
+type parseFn func(*Node, Lexer) (parseFn, *Node, error)
+
+func Parse(lexer Lexer) (*Node, error) {
+	var parser parseFn
+
+	root := NewNode(KindPattern, nil)
+
+	var (
+		tree *Node
+		err  error
+	)
+	for parser, tree = parserMain, root; parser != nil; {
+		parser, tree, err = parser(tree, lexer)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	return root, nil
+}
+
+func parserMain(tree *Node, lex Lexer) (parseFn, *Node, error) {
+	for {
+		token := lex.Next()
+		switch token.Type {
+		case lexer.EOF:
+			return nil, tree, nil
+
+		case lexer.Error:
+			return nil, tree, errors.New(token.Raw)
+
+		case lexer.Text:
+			Insert(tree, NewNode(KindText, Text{token.Raw}))
+			return parserMain, tree, nil
+
+		case lexer.Any:
+			Insert(tree, NewNode(KindAny, nil))
+			return parserMain, tree, nil
+
+		case lexer.Super:
+			Insert(tree, NewNode(KindSuper, nil))
+			return parserMain, tree, nil
+
+		case lexer.Single:
+			Insert(tree, NewNode(KindSingle, nil))
+			return parserMain, tree, nil
+
+		case lexer.RangeOpen:
+			return parserRange, tree, nil
+
+		case lexer.TermsOpen:
+			a := NewNode(KindAnyOf, nil)
+			Insert(tree, a)
+
+			p := NewNode(KindPattern, nil)
+			Insert(a, p)
+
+			return parserMain, p, nil
+
+		case lexer.Separator:
+			p := NewNode(KindPattern, nil)
+			Insert(tree.Parent, p)
+
+			return parserMain, p, nil
+
+		case lexer.TermsClose:
+			return parserMain, tree.Parent.Parent, nil
+
+		default:
+			return nil, tree, fmt.Errorf("unexpected token: %s", token)
+		}
+	}
+	return nil, tree, fmt.Errorf("unknown error")
+}
+
+func parserRange(tree *Node, lex Lexer) (parseFn, *Node, error) {
+	var (
+		not   bool
+		lo    rune
+		hi    rune
+		chars string
+	)
+	for {
+		token := lex.Next()
+		switch token.Type {
+		case lexer.EOF:
+			return nil, tree, errors.New("unexpected end")
+
+		case lexer.Error:
+			return nil, tree, errors.New(token.Raw)
+
+		case lexer.Not:
+			not = true
+
+		case lexer.RangeLo:
+			r, w := utf8.DecodeRuneInString(token.Raw)
+			if len(token.Raw) > w {
+				return nil, tree, fmt.Errorf("unexpected length of lo character")
+			}
+			lo = r
+
+		case lexer.RangeBetween:
+			//
+
+		case lexer.RangeHi:
+			r, w := utf8.DecodeRuneInString(token.Raw)
+			if len(token.Raw) > w {
+				return nil, tree, fmt.Errorf("unexpected length of lo character")
+			}
+
+			hi = r
+
+			if hi < lo {
+				return nil, tree, fmt.Errorf("hi character '%s' should be greater than lo '%s'", string(hi), string(lo))
+			}
+
+		case lexer.Text:
+			chars = token.Raw
+
+		case lexer.RangeClose:
+			isRange := lo != 0 && hi != 0
+			isChars := chars != ""
+
+			if isChars == isRange {
+				return nil, tree, fmt.Errorf("could not parse range")
+			}
+
+			if isRange {
+				Insert(tree, NewNode(KindRange, Range{
+					Lo:  lo,
+					Hi:  hi,
+					Not: not,
+				}))
+			} else {
+				Insert(tree, NewNode(KindList, List{
+					Chars: chars,
+					Not:   not,
+				}))
+			}
+
+			return parserMain, tree, nil
+		}
+	}
+}