formatter mustcompile

formatters.go

@@ -75,20 +75,13 @@ func (f *csvFormatter) Close() error {
 type yamlFormatter struct {
  w io.Writer
  columns []*sql.ColumnType
- parser *parser
 }
 
 // YAML returns an initialized YAML formatter.
 func YAML(w io.Writer, columns []*sql.ColumnType) (Formatter, error) {
- p, err := newParser()
- if err != nil {
- return nil, err
- }
-
  f := yamlFormatter{
  w: w,
  columns: columns,
- parser: p,
  }
 
  return &f, nil
@@ -100,7 +93,7 @@ func (f *yamlFormatter) Format(record [][]byte) error {
  return errors.New("record length does not match number of columns")
  }
 
- m, err := buildMap(record, f.columns, f.parser)
+ m, err := buildMap(record, f.columns)
  if err != nil {
  return fmt.Errorf("transforming data: %w", err)
  }
@@ -128,20 +121,13 @@ type jsonFormatter struct {
  w io.Writer
  columns []*sql.ColumnType
  notFirst bool
- parser *parser
 }
 
 // JSON opens a JSON array and returns an initialized JSON formatter.
 func JSON(w io.Writer, columns []*sql.ColumnType) (Formatter, error) {
- p, err := newParser()
- if err != nil {
- return nil, err
- }
-
  f := jsonFormatter{
  w: w,
  columns: columns,
- parser: p,
  }
 
  if err := f.writeByte(openBracket); err != nil {
@@ -157,7 +143,7 @@ func (f *jsonFormatter) Format(record [][]byte) error {
  return errors.New("record length does not match number of columns")
  }
 
- m, err := buildMap(record, f.columns, f.parser)
+ m, err := buildMap(record, f.columns)
  if err != nil {
  return fmt.Errorf("transforming data: %w", err)
  }
@@ -195,32 +181,15 @@ func (f *jsonFormatter) writeByte(b byte) error {
  return nil
 }
 
-type parser struct {
- boolRegex *regexp.Regexp
- intRegex *regexp.Regexp
- decimalRegex *regexp.Regexp
-}
-
-func newParser() (*parser, error) {
- var (
- boolRegex, boolErr = regexp.Compile("BOOL*")
- intRegex, intErr = regexp.Compile("INT*")
- decimalRegex, decimalErr = regexp.Compile("DECIMAL*|FLOAT*|NUMERIC*|DOUBLE*")
- )
- if boolErr != nil || intErr != nil || decimalErr != nil {
- return nil, errors.New("initializing parser regex")
- }
-
- p := parser{
- boolRegex: boolRegex,
- intRegex: intRegex,
- decimalRegex: decimalRegex,
- }
-
- return &p, nil
+var pattern = struct {
+ boolean, integer, float *regexp.Regexp
+}{
+ boolean: regexp.MustCompile("BOOL*"),
+ integer: regexp.MustCompile("INT*"),
+ float: regexp.MustCompile("DECIMAL*|FLOAT*|NUMERIC*|DOUBLE*"),
 }
 
-func (p *parser) parse(b []byte, t string) (interface{}, error) {
+func parse(b []byte, t string) (interface{}, error) {
  if b == nil {
  return nil, nil
  }
@@ -229,21 +198,21 @@ func (p *parser) parse(b []byte, t string) (interface{}, error) {
  s = string(b)
  )
  switch {
- case p.boolRegex.MatchString(t):
+ case pattern.boolean.MatchString(t):
  return strconv.ParseBool(s)
- case p.intRegex.MatchString(t):
+ case pattern.integer.MatchString(t):
  return strconv.Atoi(s)
- case p.decimalRegex.MatchString(t):
+ case pattern.float.MatchString(t):
  return strconv.ParseFloat(s, 64)
  default:
  return s, nil
  }
 }
 
-func buildMap(record [][]byte, columns []*sql.ColumnType, p *parser) (map[string]interface{}, error) {
+func buildMap(record [][]byte, columns []*sql.ColumnType) (map[string]interface{}, error) {
  m := make(map[string]interface{})
  for i, column := range columns {
- r, err := p.parse(record[i], columns[i].DatabaseTypeName())
+ r, err := parse(record[i], columns[i].DatabaseTypeName())
  if err != nil {
  return nil, err
  }