refactoring and gouncritic, 1st part

lib/helpers.go

@@ -41,11 +41,11 @@ func contains(s []int, e int) bool {
 
 // parse columns list given  with -c, modifies config.UseColumns based
 // on eventually given regex
-func PrepareColumns(c *cfg.Config, data *Tabdata) error {
-	if len(c.Columns) > 0 {
-		for _, use := range strings.Split(c.Columns, ",") {
+func PrepareColumns(conf *cfg.Config, data *Tabdata) error {
+	if len(conf.Columns) > 0 {
+		for _, use := range strings.Split(conf.Columns, ",") {
 			if len(use) == 0 {
-				msg := fmt.Sprintf("Could not parse columns list %s: empty column", c.Columns)
+				msg := fmt.Sprintf("Could not parse columns list %s: empty column", conf.Columns)
 				return errors.New(msg)
 			}
 
@@ -54,14 +54,14 @@ func PrepareColumns(c *cfg.Config, data *Tabdata) error {
 				// might be a regexp
 				colPattern, err := regexp.Compile(use)
 				if err != nil {
-					msg := fmt.Sprintf("Could not parse columns list %s: %v", c.Columns, err)
+					msg := fmt.Sprintf("Could not parse columns list %s: %v", conf.Columns, err)
 					return errors.New(msg)
 				}
 
 				// find matching header fields
 				for i, head := range data.headers {
 					if colPattern.MatchString(head) {
-						c.UseColumns = append(c.UseColumns, i+1)
+						conf.UseColumns = append(conf.UseColumns, i+1)
 					}
 
 				}
@@ -70,45 +70,45 @@ func PrepareColumns(c *cfg.Config, data *Tabdata) error {
 				// a colum spec is not a number, we process them above
 				// inside the err handler  for atoi(). so only add the
 				// number, if it's really just a number.
-				c.UseColumns = append(c.UseColumns, usenum)
+				conf.UseColumns = append(conf.UseColumns, usenum)
 			}
 		}
 
 		// deduplicate: put all values into a map (value gets map key)
 		// thereby  removing duplicates,  extract keys into  new slice
 		// and sort it
-		imap := make(map[int]int, len(c.UseColumns))
-		for _, i := range c.UseColumns {
+		imap := make(map[int]int, len(conf.UseColumns))
+		for _, i := range conf.UseColumns {
 			imap[i] = 0
 		}
-		c.UseColumns = nil
+		conf.UseColumns = nil
 		for k := range imap {
-			c.UseColumns = append(c.UseColumns, k)
+			conf.UseColumns = append(conf.UseColumns, k)
 		}
-		sort.Ints(c.UseColumns)
+		sort.Ints(conf.UseColumns)
 	}
 	return nil
 }
 
 // prepare headers: add numbers to headers
-func numberizeAndReduceHeaders(c cfg.Config, data *Tabdata) {
+func numberizeAndReduceHeaders(conf cfg.Config, data *Tabdata) {
 	numberedHeaders := []string{}
 	maxwidth := 0 // start from scratch, so we only look at displayed column widths
 
-	for i, head := range data.headers {
+	for idx, head := range data.headers {
 		headlen := 0
-		if len(c.Columns) > 0 {
+		if len(conf.Columns) > 0 {
 			// -c specified
-			if !contains(c.UseColumns, i+1) {
+			if !contains(conf.UseColumns, idx+1) {
 				// ignore this one
 				continue
 			}
 		}
-		if c.NoNumbering {
+		if conf.NoNumbering {
 			numberedHeaders = append(numberedHeaders, head)
 			headlen = len(head)
 		} else {
-			numhead := fmt.Sprintf("%s(%d)", head, i+1)
+			numhead := fmt.Sprintf("%s(%d)", head, idx+1)
 			headlen = len(numhead)
 			numberedHeaders = append(numberedHeaders, numhead)
 		}
@@ -124,14 +124,14 @@ func numberizeAndReduceHeaders(c cfg.Config, data *Tabdata) {
 }
 
 // exclude columns, if any
-func reduceColumns(c cfg.Config, data *Tabdata) {
-	if len(c.Columns) > 0 {
+func reduceColumns(conf cfg.Config, data *Tabdata) {
+	if len(conf.Columns) > 0 {
 		reducedEntries := [][]string{}
 		var reducedEntry []string
 		for _, entry := range data.entries {
 			reducedEntry = nil
 			for i, value := range entry {
-				if !contains(c.UseColumns, i+1) {
+				if !contains(conf.UseColumns, i+1) {
 					continue
 				}
 
@@ -153,8 +153,9 @@ func trimRow(row []string) []string {
 	return fixedrow
 }
 
-func colorizeData(c cfg.Config, output string) string {
-	if c.UseHighlight && color.IsConsole(os.Stdout) {
+func colorizeData(conf cfg.Config, output string) string {
+	switch {
+	case conf.UseHighlight && color.IsConsole(os.Stdout):
 		highlight := true
 		colorized := ""
 		first := true
@@ -167,17 +168,17 @@ func colorizeData(c cfg.Config, output string) string {
 					//  in pprint mode. This doesn't matter as long as
 					//  we don't use colorization. But with colors the
 					// missing spaces can be seen.
-					if c.OutputMode == cfg.Ascii {
-						line = line + "  "
+					if conf.OutputMode == cfg.ASCII {
+						line += "  "
 					}
 
-					line = c.HighlightHdrStyle.Sprint(line)
+					line = conf.HighlightHdrStyle.Sprint(line)
 					first = false
 				} else {
-					line = c.HighlightStyle.Sprint(line)
+					line = conf.HighlightStyle.Sprint(line)
 				}
 			} else {
-				line = c.NoHighlightStyle.Sprint(line)
+				line = conf.NoHighlightStyle.Sprint(line)
 			}
 			highlight = !highlight
 
@@ -185,12 +186,12 @@ func colorizeData(c cfg.Config, output string) string {
 		}
 
 		return colorized
-	} else if len(c.Pattern) > 0 && !c.NoColor && color.IsConsole(os.Stdout) {
-		r := regexp.MustCompile("(" + c.Pattern + ")")
+	case len(conf.Pattern) > 0 && !conf.NoColor && color.IsConsole(os.Stdout):
+		r := regexp.MustCompile("(" + conf.Pattern + ")")
 		return r.ReplaceAllStringFunc(output, func(in string) string {
-			return c.ColorStyle.Sprint(in)
+			return conf.ColorStyle.Sprint(in)
 		})
-	} else {
+	default:
 		return output
 	}
 }