Method parseIf

parser/parser.go:416–487

()

}

func (p *parser) parseIf() error {
	s := p.s
	t, err := expectTagContents(s)
	if err != nil {
		return err
	}
	if len(t.Value) == 0 {
		return fmt.Errorf("empty if condition at %s", s.Context())
	}
	ifStr := "if " + string(t.Value)
	if err = validateIfStmt(t.Value); err != nil {
		return fmt.Errorf("invalid statement %q at %s: %s", ifStr, s.Context(), err)
	}
	p.Printf("if %s {", t.Value)
	p.prefix += "\t"
	elseUsed := false
	for s.Next() {
		t := s.Token()
		switch t.ID {
		case text:
			p.emitText(t.Value)
		case tagName:
			ok, err := p.tryParseCommonTags(t.Value)
			if err != nil {
				return fmt.Errorf("error in %q: %s", ifStr, err)
			}
			if ok {
				continue
			}
			switch string(t.Value) {
			case "endif":
				if err = skipTagContents(s); err != nil {
					return err
				}
				p.prefix = p.prefix[1:]
				p.Printf("}")
				return nil
			case "else":
				if elseUsed {
					return fmt.Errorf("duplicate else branch found for %q at %s", ifStr, s.Context())
				}
				if err = skipTagContents(s); err != nil {
					return err
				}
				p.prefix = p.prefix[1:]
				p.Printf("} else {")
				p.prefix += "\t"
				elseUsed = true
			case "elseif":
				if elseUsed {
					return fmt.Errorf("unexpected elseif branch found after else branch for %q at %s",
						ifStr, s.Context())
				}
				t, err = expectTagContents(s)
				if err != nil {
					return err
				}
				p.prefix = p.prefix[1:]