changed file handling, use -r <file> or nothing to use stdin

cmd/root.go

@@ -196,8 +196,14 @@ func Execute() {
 		"config file (default: ~/.config/tablizer/config)")
 
 	// filters
-	rootCmd.PersistentFlags().StringArrayVarP(&conf.Rawfilters, "filter", "F", nil, "Filter by field (field=regexp)")
-	rootCmd.PersistentFlags().StringArrayVarP(&conf.Transposers, "regex-transposer", "R", nil, "apply /search/replace/ regexp to fields given in -T")
+	rootCmd.PersistentFlags().StringArrayVarP(&conf.Rawfilters,
+		"filter", "F", nil, "Filter by field (field=regexp)")
+	rootCmd.PersistentFlags().StringArrayVarP(&conf.Transposers,
+		"regex-transposer", "R", nil, "apply /search/replace/ regexp to fields given in -T")
+
+	// input
+	rootCmd.PersistentFlags().StringVarP(&conf.InputFile, "read-file", "r", "",
+		"Read input data from file")
 
 	rootCmd.SetUsageTemplate(strings.TrimSpace(usage) + "\n")
 

lib/helpers.go

@@ -121,19 +121,25 @@ func PrepareColumnVars(columns string, data *Tabdata) ([]int, error) {
 				// is not a regexp (contains no non-word chars)
 				// lc() it so that word searches are case insensitive
 				columnpattern = strings.ToLower(columnpattern)
-			}
 
-			colPattern, err := regexp.Compile(columnpattern)
-			if err != nil {
-				msg := fmt.Sprintf("Could not parse columns list %s: %v", columns, err)
+				for i, head := range data.headers {
+					if columnpattern == strings.ToLower(head) {
+						usecolumns = append(usecolumns, i+1)
+					}
+				}
+			} else {
+				colPattern, err := regexp.Compile("(?i)" + columnpattern)
+				if err != nil {
+					msg := fmt.Sprintf("Could not parse columns list %s: %v", columns, err)
 
-				return nil, errors.New(msg)
-			}
+					return nil, errors.New(msg)
+				}
 
-			// find matching header fields, ignoring case
-			for i, head := range data.headers {
-				if colPattern.MatchString(strings.ToLower(head)) {
-					usecolumns = append(usecolumns, i+1)
+				// find matching header fields, ignoring case
+				for i, head := range data.headers {
+					if colPattern.MatchString(strings.ToLower(head)) {
+						usecolumns = append(usecolumns, i+1)
+					}
 				}
 			}
 		} else {

lib/helpers_test.go

@@ -67,8 +67,8 @@ func TestPrepareColumns(t *testing.T) {
 	}{
 		{"1,2,3", []int{1, 2, 3}, false},
 		{"1,2,", []int{}, true},
-		{"T", []int{2, 3}, false},
-		{"T,2,3", []int{2, 3}, false},
+		{"T.", []int{2, 3}, false},
+		{"T.,2,3", []int{2, 3}, false},
 		{"[a-z,4,5", []int{4, 5}, true}, // invalid regexp
 	}
 
@@ -117,13 +117,13 @@ func TestPrepareTransposerColumns(t *testing.T) {
 			false,
 		},
 		{
-			"T", // will match [T]WO and [T]HREE
+			"T.", // will match [T]WO and [T]HREE
 			[]string{`/\d/x/`, `/.//`},
 			2,
 			false,
 		},
 		{
-			"T,2",
+			"TH.,2",
 			[]string{`/\d/x/`, `/.//`},
 			2,
 			false,

lib/io.go

@@ -29,7 +29,7 @@ import (
 const RWRR = 0755
 
 func ProcessFiles(conf *cfg.Config, args []string) error {
-	fds, pattern, err := determineIO(conf, args)
+	fd, pattern, err := determineIO(conf, args)
 
 	if err != nil {
 		return err
@@ -39,28 +39,67 @@ func ProcessFiles(conf *cfg.Config, args []string) error {
 		return err
 	}
 
-	for _, fd := range fds {
-		data, err := Parse(*conf, fd)
-		if err != nil {
-			return err
-		}
-
-		if err = ValidateConsistency(&data); err != nil {
-			return err
-		}
-
-		err = PrepareColumns(conf, &data)
-		if err != nil {
-			return err
-		}
-
-		printData(os.Stdout, *conf, &data)
+	data, err := Parse(*conf, fd)
+	if err != nil {
+		return err
 	}
 
+	if err = ValidateConsistency(&data); err != nil {
+		return err
+	}
+
+	err = PrepareColumns(conf, &data)
+	if err != nil {
+		return err
+	}
+
+	printData(os.Stdout, *conf, &data)
+
 	return nil
 }
 
-func determineIO(conf *cfg.Config, args []string) ([]io.Reader, string, error) {
+func determineIO(conf *cfg.Config, args []string) (io.Reader, string, error) {
+	var filehandle io.Reader
+	var pattern string
+	var haveio bool
+
+	switch {
+	case conf.InputFile == "-":
+		filehandle = os.Stdin
+		haveio = true
+	case conf.InputFile != "":
+		fd, err := os.OpenFile(conf.InputFile, os.O_RDONLY, RWRR)
+
+		if err != nil {
+			return nil, "", fmt.Errorf("failed to read input file %s: %w", conf.InputFile, err)
+		}
+
+		filehandle = fd
+		haveio = true
+	}
+
+	if !haveio {
+		stat, _ := os.Stdin.Stat()
+		if (stat.Mode() & os.ModeCharDevice) == 0 {
+			// we're reading from STDIN, which takes precedence over file args
+			filehandle = os.Stdin
+			haveio = true
+		}
+	}
+
+	if len(args) > 0 {
+		pattern = args[0]
+		conf.Pattern = args[0]
+	}
+
+	if !haveio {
+		return nil, "", errors.New("no file specified and nothing to read on stdin")
+	}
+
+	return filehandle, pattern, nil
+}
+
+func _determineIO(conf *cfg.Config, args []string) ([]io.Reader, string, error) {
 	var filehandles []io.Reader
 
 	var pattern string
@@ -80,7 +119,7 @@ func determineIO(conf *cfg.Config, args []string) ([]io.Reader, string, error) {
 
 		haveio = true
 	} else if len(args) > 0 {
-		// threre were args left, take a look
+		// there were args left, take a look
 		if args[0] == "-" {
 			// in traditional unix programs a dash denotes STDIN (forced)
 			filehandles = append(filehandles, os.Stdin)