Make parser compatible with Go 1.12

See changes in strings.Map(): https://golang.org/doc/go1.12#strings

reader/parser/parser.go

@@ -8,7 +8,6 @@ import (
 	"strings"
 
 	"miniflux.app/errors"
-	"miniflux.app/logger"
 	"miniflux.app/model"
 	"miniflux.app/reader/atom"
 	"miniflux.app/reader/json"
@@ -18,8 +17,6 @@ import (
 
 // ParseFeed analyzes the input data and returns a normalized feed object.
 func ParseFeed(data string) (*model.Feed, *errors.LocalizedError) {
-	data = stripInvalidXMLCharacters(data)
-
 	switch DetectFeedFormat(data) {
 	case FormatAtom:
 		return atom.Parse(strings.NewReader(data))
@@ -33,26 +30,3 @@ func ParseFeed(data string) (*model.Feed, *errors.LocalizedError) {
 		return nil, errors.NewLocalizedError("Unsupported feed format")
 	}
 }
-
-func stripInvalidXMLCharacters(input string) string {
-	return strings.Map(func(r rune) rune {
-		if isInCharacterRange(r) {
-			return r
-		}
-
-		logger.Debug("Strip invalid XML characters: %U", r)
-		return -1
-	}, input)
-}
-
-// Decide whether the given rune is in the XML Character Range, per
-// the Char production of http://www.xml.com/axml/testaxml.htm,
-// Section 2.2 Characters.
-func isInCharacterRange(r rune) (inrange bool) {
-	return r == 0x09 ||
-		r == 0x0A ||
-		r == 0x0D ||
-		r >= 0x20 && r <= 0xDF77 ||
-		r >= 0xE000 && r <= 0xFFFD ||
-		r >= 0x10000 && r <= 0x10FFFF
-}

reader/parser/parser_test.go

@@ -187,7 +187,10 @@ func TestDifferentEncodingWithResponse(t *testing.T) {
 		}
 
 		r := &client.Response{Body: bytes.NewReader(content), ContentType: tc.contentType}
-		r.EnsureUnicodeBody()
+		if encodingErr := r.EnsureUnicodeBody(); encodingErr != nil {
+			t.Fatalf(`Encoding error for %q: %v`, tc.filename, encodingErr)
+		}
+
 		feed, parseErr := ParseFeed(r.String())
 		if parseErr != nil {
 			t.Fatalf(`Parsing error for %q - %q: %v`, tc.filename, tc.contentType, parseErr)