diff options
Diffstat (limited to 'vendor/github.com/tdewolff/minify/xml/xml.go')
| -rw-r--r-- | vendor/github.com/tdewolff/minify/xml/xml.go | 193 |
1 files changed, 193 insertions, 0 deletions
diff --git a/vendor/github.com/tdewolff/minify/xml/xml.go b/vendor/github.com/tdewolff/minify/xml/xml.go new file mode 100644 index 0000000..7974484 --- /dev/null +++ b/vendor/github.com/tdewolff/minify/xml/xml.go @@ -0,0 +1,193 @@ +// Package xml minifies XML1.0 following the specifications at http://www.w3.org/TR/xml/. +package xml // import "github.com/tdewolff/minify/xml" + +import ( + "io" + + "github.com/tdewolff/minify" + "github.com/tdewolff/parse" + "github.com/tdewolff/parse/xml" +) + +var ( + isBytes = []byte("=") + spaceBytes = []byte(" ") + voidBytes = []byte("/>") +) + +//////////////////////////////////////////////////////////////// + +// DefaultMinifier is the default minifier. +var DefaultMinifier = &Minifier{} + +// Minifier is an XML minifier. +type Minifier struct { + KeepWhitespace bool +} + +// Minify minifies XML data, it reads from r and writes to w. +func Minify(m *minify.M, w io.Writer, r io.Reader, params map[string]string) error { + return DefaultMinifier.Minify(m, w, r, params) +} + +// Minify minifies XML data, it reads from r and writes to w. +func (o *Minifier) Minify(m *minify.M, w io.Writer, r io.Reader, _ map[string]string) error { + omitSpace := true // on true the next text token must not start with a space + + attrByteBuffer := make([]byte, 0, 64) + + l := xml.NewLexer(r) + defer l.Restore() + + tb := NewTokenBuffer(l) + for { + t := *tb.Shift() + if t.TokenType == xml.CDATAToken { + if text, useText := xml.EscapeCDATAVal(&attrByteBuffer, t.Text); useText { + t.TokenType = xml.TextToken + t.Data = text + } + } + switch t.TokenType { + case xml.ErrorToken: + if l.Err() == io.EOF { + return nil + } + return l.Err() + case xml.DOCTYPEToken: + if _, err := w.Write(t.Data); err != nil { + return err + } + case xml.CDATAToken: + if _, err := w.Write(t.Data); err != nil { + return err + } + if len(t.Text) > 0 && parse.IsWhitespace(t.Text[len(t.Text)-1]) { + omitSpace = true + } + case xml.TextToken: + t.Data = parse.ReplaceMultipleWhitespace(t.Data) + + // whitespace removal; trim left + if omitSpace && (t.Data[0] == ' ' || t.Data[0] == '\n') { + t.Data = t.Data[1:] + } + + // whitespace removal; trim right + omitSpace = false + if len(t.Data) == 0 { + omitSpace = true + } else if t.Data[len(t.Data)-1] == ' ' || t.Data[len(t.Data)-1] == '\n' { + omitSpace = true + i := 0 + for { + next := tb.Peek(i) + // trim if EOF, text token with whitespace begin or block token + if next.TokenType == xml.ErrorToken { + t.Data = t.Data[:len(t.Data)-1] + omitSpace = false + break + } else if next.TokenType == xml.TextToken { + // this only happens when a comment, doctype, cdata startpi tag was in between + // remove if the text token starts with a whitespace + if len(next.Data) > 0 && parse.IsWhitespace(next.Data[0]) { + t.Data = t.Data[:len(t.Data)-1] + omitSpace = false + } + break + } else if next.TokenType == xml.CDATAToken { + if len(next.Text) > 0 && parse.IsWhitespace(next.Text[0]) { + t.Data = t.Data[:len(t.Data)-1] + omitSpace = false + } + break + } else if next.TokenType == xml.StartTagToken || next.TokenType == xml.EndTagToken { + if !o.KeepWhitespace { + t.Data = t.Data[:len(t.Data)-1] + omitSpace = false + } + break + } + i++ + } + } + + if _, err := w.Write(t.Data); err != nil { + return err + } + case xml.StartTagToken: + if o.KeepWhitespace { + omitSpace = false + } + if _, err := w.Write(t.Data); err != nil { + return err + } + case xml.StartTagPIToken: + if _, err := w.Write(t.Data); err != nil { + return err + } + case xml.AttributeToken: + if _, err := w.Write(spaceBytes); err != nil { + return err + } + if _, err := w.Write(t.Text); err != nil { + return err + } + if _, err := w.Write(isBytes); err != nil { + return err + } + + if len(t.AttrVal) < 2 { + if _, err := w.Write(t.AttrVal); err != nil { + return err + } + } else { + // prefer single or double quotes depending on what occurs more often in value + val := xml.EscapeAttrVal(&attrByteBuffer, t.AttrVal[1:len(t.AttrVal)-1]) + if _, err := w.Write(val); err != nil { + return err + } + } + case xml.StartTagCloseToken: + next := tb.Peek(0) + skipExtra := false + if next.TokenType == xml.TextToken && parse.IsAllWhitespace(next.Data) { + next = tb.Peek(1) + skipExtra = true + } + if next.TokenType == xml.EndTagToken { + // collapse empty tags to single void tag + tb.Shift() + if skipExtra { + tb.Shift() + } + if _, err := w.Write(voidBytes); err != nil { + return err + } + } else { + if _, err := w.Write(t.Text); err != nil { + return err + } + } + case xml.StartTagCloseVoidToken: + if _, err := w.Write(t.Text); err != nil { + return err + } + case xml.StartTagClosePIToken: + if _, err := w.Write(t.Text); err != nil { + return err + } + case xml.EndTagToken: + if o.KeepWhitespace { + omitSpace = false + } + if len(t.Data) > 3+len(t.Text) { + t.Data[2+len(t.Text)] = '>' + t.Data = t.Data[:3+len(t.Text)] + } + if _, err := w.Write(t.Data); err != nil { + return err + } + } + } +} |