re-organized pattern matching code

CHANGELOG.md

@@ -4,6 +4,36 @@ All notable changes to this project will be documented in this file.
 
 The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/) and this project adheres to [Semantic Versioning](http://semver.org).
 
+## [v1.0.12](https://github.com/TLINDEN/tablizer/tree/v1.0.12) - 2022-10-25
+
+[Full Changelog](https://github.com/TLINDEN/tablizer/compare/v1.0.11...v1.0.12)
+
+### Added
+
+- Added support to parse CSV input
+
+- Added CSV output support
+
+- Added support for environment variables
+
+### Changed
+
+- We do not use the generated help message anymore, instead we use the
+  usage from the  manpage, which we have to maintain  anyway. It looks
+  better and has flag groups, which  cobra is still lacking as of this
+  writing.
+  
+-  More refactoring  and  re-organization,  runtime configuration  now
+  lives in the cfg module.
+  
+  
+### Fixed
+
+- Fixed  [Bug #5](https://github.com/TLINDEN/tablizer/issues/5), where
+  matches have not been highlighted correctly in some rare cases.
+
+
+
 ## [v1.0.11](https://github.com/TLINDEN/tablizer/tree/v1.0.11) - 2022-10-19
 
 [Full Changelog](https://github.com/TLINDEN/tablizer/compare/v1.0.10...v1.0.11)

Makefile

@@ -41,6 +41,10 @@ cmd/%.go: %.pod
 	pod2text $*.pod >> cmd/$*.go
 	echo "\`" >> cmd/$*.go
 
+	echo "var usage = \`" >> cmd/$*.go
+	awk '/SYNOPS/{f=1;next} /DESCR/{f=0} f' $*.pod  | sed 's/^    //' >> cmd/$*.go
+	echo "\`" >> cmd/$*.go
+
 buildlocal:
 	go build -ldflags "-X 'github.com/tlinden/tablizer/cfg.VERSION=$(VERSION)'"
 

TODO.md

@@ -1,15 +1,9 @@
 ## Fixes to be implemented
 
-- rm printYamlData() log.Fatal(), maybe return error on all printers?
-
-- printShellData() checks Columns unnecessarily (compare to yaml or extended)
-
 ## Features to be implemented
 
-- add output mode csv
+- add comment support (csf.NewReader().Comment = '#')
 
 - add --no-headers option
 
--  add input  parsing support  for CSV  including unquoting  of stuff
-  like: `"xxx","1919 b"` etc, maybe an extra option for unquoting
 

cfg/config.go

@@ -20,12 +20,12 @@ import (
 	"errors"
 	"fmt"
 	"github.com/gookit/color"
+	"os"
 	"regexp"
 )
 
 const DefaultSeparator string = `(\s\s+|\t)`
-const ValidOutputModes string = "(orgtbl|markdown|extended|ascii|yaml|shell)"
+const Version string = "v1.0.12"
-const Version string = "v1.0.11"
 
 var VERSION string // maintained by -x
 
@@ -35,9 +35,10 @@ type Config struct {
 	Columns     string
 	UseColumns  []int
 	Separator   string
-	OutputMode  string
+	OutputMode  int
 	InvertMatch bool
 	Pattern     string
+	PatternR    *regexp.Regexp
 
 	SortMode       string
 	SortDescending bool
@@ -45,12 +46,10 @@ type Config struct {
 
 	/*
 	 FIXME: make configurable somehow, config file or ENV
-	 see https://github.com/gookit/color will be set by
+	 see https://github.com/gookit/color.
-	 io.ProcessFiles() according to currently supported
-	 color mode.
 	*/
-	MatchFG string
+	ColorStyle color.Style
-	MatchBG string
+
 	NoColor bool
 }
 
@@ -62,8 +61,20 @@ type Modeflag struct {
 	S bool
 	Y bool
 	A bool
+	C bool
 }
 
+// used for switching printers
+const (
+	Extended = iota + 1
+	Orgtbl
+	Markdown
+	Shell
+	Yaml
+	CSV
+	Ascii
+)
+
 // various sort types
 type Sortmode struct {
 	Numeric bool
@@ -71,22 +82,43 @@ type Sortmode struct {
 	Age     bool
 }
 
-func Colors() map[color.Level]map[string]string {
 // default color schemes
-	return map[color.Level]map[string]string{
+func Colors() map[color.Level]map[string]color.Color {
+	return map[color.Level]map[string]color.Color{
 		color.Level16: {
-			"bg": "green", "fg": "black",
+			"bg": color.BgGreen, "fg": color.FgBlack,
 		},
 		color.Level256: {
-			"bg": "lightGreen", "fg": "black",
+			"bg": color.BgLightGreen, "fg": color.FgBlack,
 		},
 		color.LevelRgb: {
 			// FIXME: maybe use something nicer
-			"bg": "lightGreen", "fg": "black",
+			"bg": color.BgLightGreen, "fg": color.FgBlack,
 		},
 	}
 }
 
+// find supported color mode, modifies config based on constants
+func (c *Config) DetermineColormode() {
+	if !isTerminal(os.Stdout) {
+		color.Disable()
+	} else {
+		level := color.TermColorLevel()
+		colors := Colors()
+		c.ColorStyle = color.New(colors[level]["bg"], colors[level]["fg"])
+	}
+}
+
+// Return true if current terminal is interactive
+func isTerminal(f *os.File) bool {
+	o, _ := f.Stat()
+	if (o.Mode() & os.ModeCharDevice) == os.ModeCharDevice {
+		return true
+	} else {
+		return false
+	}
+}
+
 func Getversion() string {
 	// main program version
 
@@ -97,39 +129,6 @@ func Getversion() string {
 	return fmt.Sprintf("This is tablizer version %s", VERSION)
 }
 
-func (conf *Config) PrepareModeFlags(flag Modeflag, mode string) error {
-	if len(mode) == 0 {
-		// associate short flags like -X with mode selector
-		switch {
-		case flag.X:
-			conf.OutputMode = "extended"
-		case flag.M:
-			conf.OutputMode = "markdown"
-		case flag.O:
-			conf.OutputMode = "orgtbl"
-		case flag.S:
-			conf.OutputMode = "shell"
-			conf.NoNumbering = true
-		case flag.Y:
-			conf.OutputMode = "yaml"
-			conf.NoNumbering = true
-		default:
-			conf.OutputMode = "ascii"
-		}
-	} else {
-		r, _ := regexp.Compile(ValidOutputModes) // hardcoded, no fail expected
-		match := r.MatchString(mode)
-
-		if !match {
-			return errors.New("Invalid output mode!")
-		}
-
-		conf.OutputMode = mode
-	}
-
-	return nil
-}
-
 func (conf *Config) PrepareSortFlags(flag Sortmode) {
 	switch {
 	case flag.Numeric:
@@ -142,3 +141,60 @@ func (conf *Config) PrepareSortFlags(flag Sortmode) {
 		conf.SortMode = "string"
 	}
 }
+
+func (conf *Config) PrepareModeFlags(flag Modeflag) {
+	switch {
+	case flag.X:
+		conf.OutputMode = Extended
+	case flag.O:
+		conf.OutputMode = Orgtbl
+	case flag.M:
+		conf.OutputMode = Markdown
+	case flag.S:
+		conf.OutputMode = Shell
+	case flag.Y:
+		conf.OutputMode = Yaml
+	case flag.C:
+		conf.OutputMode = CSV
+	default:
+		conf.OutputMode = Ascii
+	}
+}
+
+func (c *Config) CheckEnv() {
+	// check for environment vars, command line flags have precedence,
+	// NO_COLOR is being checked by the color module itself.
+	if !c.NoNumbering {
+		_, set := os.LookupEnv("T_NO_HEADER_NUMBERING")
+		if set {
+			c.NoNumbering = true
+		}
+	}
+
+	if len(c.Columns) == 0 {
+		cols := os.Getenv("T_COLUMNS")
+		if len(cols) > 1 {
+			c.Columns = cols
+		}
+	}
+}
+
+func (c *Config) ApplyDefaults() {
+	// mode specific defaults
+	if c.OutputMode == Yaml || c.OutputMode == CSV {
+		c.NoNumbering = true
+	}
+}
+
+func (c *Config) PreparePattern(pattern string) error {
+	PatternR, err := regexp.Compile(pattern)
+
+	if err != nil {
+		return errors.Unwrap(fmt.Errorf("Regexp pattern %s is invalid: %w", c.Pattern, err))
+	}
+
+	c.PatternR = PatternR
+	c.Pattern = pattern
+
+	return nil
+}

cfg/config_test.go

@@ -26,46 +26,26 @@ import (
 func TestPrepareModeFlags(t *testing.T) {
 	var tests = []struct {
 		flag   Modeflag
-		mode   string // input, if any
+		expect int // output (constant enum)
-		expect string // output
-		want   bool
 	}{
 		// short commandline flags like -M
-		{Modeflag{X: true}, "", "extended", false},
+		{Modeflag{X: true}, Extended},
-		{Modeflag{S: true}, "", "shell", false},
+		{Modeflag{S: true}, Shell},
-		{Modeflag{O: true}, "", "orgtbl", false},
+		{Modeflag{O: true}, Orgtbl},
-		{Modeflag{Y: true}, "", "yaml", false},
+		{Modeflag{Y: true}, Yaml},
-		{Modeflag{M: true}, "", "markdown", false},
+		{Modeflag{M: true}, Markdown},
-		{Modeflag{}, "", "ascii", false},
+		{Modeflag{}, Ascii},
-
-		// long flags like -o yaml
-		{Modeflag{}, "extended", "extended", false},
-		{Modeflag{}, "shell", "shell", false},
-		{Modeflag{}, "orgtbl", "orgtbl", false},
-		{Modeflag{}, "yaml", "yaml", false},
-		{Modeflag{}, "markdown", "markdown", false},
-
-		// failing
-		{Modeflag{}, "blah", "", true},
 	}
 
+	// FIXME: use a map for easier printing
 	for _, tt := range tests {
-		testname := fmt.Sprintf("PrepareModeFlags-flags-mode-%s-expect-%s-want-%t",
+		testname := fmt.Sprintf("PrepareModeFlags-expect-%d", tt.expect)
-			tt.mode, tt.expect, tt.want)
 		t.Run(testname, func(t *testing.T) {
-			c := Config{OutputMode: tt.mode}
+			c := Config{}
 
-			// check either flag or pre filled mode, whatever is defined in tt
+			c.PrepareModeFlags(tt.flag)
-			err := c.PrepareModeFlags(tt.flag, tt.mode)
-			if err != nil {
-				if !tt.want {
-					// expect to fail
-					t.Fatalf("PrepareModeFlags returned unexpected error: %s", err)
-				}
-			} else {
 			if c.OutputMode != tt.expect {
-					t.Errorf("got: %s, expect: %s", c.OutputMode, tt.expect)
+				t.Errorf("got: %d, expect: %d", c.OutputMode, tt.expect)
-				}
 			}
 		})
 	}
@@ -96,3 +76,28 @@ func TestPrepareSortFlags(t *testing.T) {
 		})
 	}
 }
+
+func TestPreparePattern(t *testing.T) {
+	var tests = []struct {
+		pattern string
+		wanterr bool
+	}{
+		{"[A-Z]+", false},
+		{"[a-z", true},
+	}
+
+	for _, tt := range tests {
+		testname := fmt.Sprintf("PreparePattern-pattern-%s-wanterr-%t", tt.pattern, tt.wanterr)
+		t.Run(testname, func(t *testing.T) {
+			c := Config{}
+
+			err := c.PreparePattern(tt.pattern)
+
+			if err != nil {
+				if !tt.wanterr {
+					t.Errorf("PreparePattern returned error: %s", err)
+				}
+			}
+		})
+	}
+}

cmd/root.go

@@ -25,6 +25,7 @@ import (
 	"log"
 	"os"
 	"os/exec"
+	"strings"
 )
 
 func man() {
@@ -48,7 +49,6 @@ func Execute() {
 	var (
 		conf        cfg.Config
 		ShowManual  bool
-		Outputmode  string
 		ShowVersion bool
 		modeflag    cfg.Modeflag
 		sortmode    cfg.Sortmode
@@ -69,16 +69,15 @@ func Execute() {
 				return nil
 			}
 
-			// prepare flags
+			// Setup
-			err := conf.PrepareModeFlags(modeflag, Outputmode)
+			conf.CheckEnv()
-			if err != nil {
+			conf.PrepareModeFlags(modeflag)
-				return err
-			}
-
 			conf.PrepareSortFlags(sortmode)
+			conf.DetermineColormode()
+			conf.ApplyDefaults()
 
 			// actual execution starts here
-			return lib.ProcessFiles(conf, args)
+			return lib.ProcessFiles(&conf, args)
 		},
 	}
 
@@ -94,26 +93,24 @@ func Execute() {
 
 	// sort options
 	rootCmd.PersistentFlags().IntVarP(&conf.SortByColumn, "sort-by", "k", 0, "Sort by column (default: 1)")
+
+	// sort mode, only 1 allowed
 	rootCmd.PersistentFlags().BoolVarP(&conf.SortDescending, "sort-desc", "D", false, "Sort in descending order (default: ascending)")
 	rootCmd.PersistentFlags().BoolVarP(&sortmode.Numeric, "sort-numeric", "i", false, "sort according to string numerical value")
 	rootCmd.PersistentFlags().BoolVarP(&sortmode.Time, "sort-time", "t", false, "sort according to time string")
 	rootCmd.PersistentFlags().BoolVarP(&sortmode.Age, "sort-age", "a", false, "sort according to age (duration) string")
+	rootCmd.MarkFlagsMutuallyExclusive("sort-desc", "sort-numeric", "sort-time", "sort-age")
 
-	// output flags, only 1 allowed, hidden, since just short cuts
+	// output flags, only 1 allowed
 	rootCmd.PersistentFlags().BoolVarP(&modeflag.X, "extended", "X", false, "Enable extended output")
 	rootCmd.PersistentFlags().BoolVarP(&modeflag.M, "markdown", "M", false, "Enable markdown table output")
 	rootCmd.PersistentFlags().BoolVarP(&modeflag.O, "orgtbl", "O", false, "Enable org-mode table output")
 	rootCmd.PersistentFlags().BoolVarP(&modeflag.S, "shell", "S", false, "Enable shell mode output")
 	rootCmd.PersistentFlags().BoolVarP(&modeflag.Y, "yaml", "Y", false, "Enable yaml output")
-	rootCmd.MarkFlagsMutuallyExclusive("extended", "markdown", "orgtbl", "shell", "yaml")
+	rootCmd.PersistentFlags().BoolVarP(&modeflag.C, "csv", "C", false, "Enable CSV output")
-	_ = rootCmd.Flags().MarkHidden("extended")
+	rootCmd.MarkFlagsMutuallyExclusive("extended", "markdown", "orgtbl", "shell", "yaml", "csv")
-	_ = rootCmd.Flags().MarkHidden("orgtbl")
-	_ = rootCmd.Flags().MarkHidden("markdown")
-	_ = rootCmd.Flags().MarkHidden("shell")
-	_ = rootCmd.Flags().MarkHidden("yaml")
 
-	// same thing but more common, takes precedence over above group
+	rootCmd.SetUsageTemplate(strings.TrimSpace(usage) + "\n")
-	rootCmd.PersistentFlags().StringVarP(&Outputmode, "output", "o", "", "Output mode - one of: orgtbl, markdown, extended, shell, ascii(default)")
 
 	err := rootCmd.Execute()
 	if err != nil {

cmd/tablizer.go

@@ -8,24 +8,33 @@ SYNOPSIS
         Usage:
           tablizer [regex] [file, ...] [flags]
     
-        Flags:
+        Operational Flags:
           -c, --columns string     Only show the speficied columns (separated by ,)
-          -d, --debug              Enable debugging
-          -h, --help               help for tablizer
           -v, --invert-match       select non-matching rows
-          -m, --man                Display manual page
           -n, --no-numbering       Disable header numbering
           -N, --no-color           Disable pattern highlighting
-          -o, --output string      Output mode - one of: orgtbl, markdown, extended, yaml, ascii(default)
+          -s, --separator string   Custom field separator
+          -k, --sort-by int        Sort by column (default: 1)
+
+        Output Flags (mutually exclusive):
           -X, --extended           Enable extended output
           -M, --markdown           Enable markdown table output
           -O, --orgtbl             Enable org-mode table output
-          -s, --separator string   Custom field separator
+          -S, --shell              Enable shell evaluable ouput
+          -Y, --yaml               Enable yaml output
+          -C, --csv                Enable CSV output
+          -A, --ascii              Default output mode, ascii tabular
+
+        Sort Mode Flags (mutually exclusive):
           -a, --sort-age           sort according to age (duration) string
-          -k, --sort-by int        Sort by column (default: 1)
           -D, --sort-desc          Sort in descending order (default: ascending)
           -i, --sort-numeric       sort according to string numerical value
           -t, --sort-time          sort according to time string
+
+        Other Flags:
+          -d, --debug              Enable debugging
+          -h, --help               help for tablizer
+          -m, --man                Display manual page
           -v, --version            Print program version
 
 DESCRIPTION
@@ -178,8 +187,17 @@ DESCRIPTION
 
     Beside normal ascii mode (the default) and extended mode there are more
     output modes available: orgtbl which prints an Emacs org-mode table and
-    markdown which prints a Markdown table and yaml, which prints yaml
+    markdown which prints a Markdown table, yaml, which prints yaml encoding
-    encoding.
+    and CSV mode, which prints a comma separated value file.
+
+  ENVIRONMENT VARIABLES
+    tablizer supports certain environment variables which use can use to
+    influence program behavior. Commandline flags have always precedence
+    over environment variables.
+
+    <T_NO_HEADER_NUMBERING> - disable numbering of header fields, like -n.
+    <T_COLUMNS> - comma separated list of columns to output, like -c
+    <NO_COLORS> - disable colorization of matches, like -N
 
 BUGS
     In order to report a bug, unexpected behavior, feature requests or to
@@ -205,3 +223,39 @@ AUTHORS
     Thomas von Dein tom AT vondein DOT org
 
 `
+var usage = `
+
+Usage:
+  tablizer [regex] [file, ...] [flags]
+
+Operational Flags:
+  -c, --columns string     Only show the speficied columns (separated by ,)
+  -v, --invert-match       select non-matching rows
+  -n, --no-numbering       Disable header numbering
+  -N, --no-color           Disable pattern highlighting
+  -s, --separator string   Custom field separator
+  -k, --sort-by int        Sort by column (default: 1)
+
+Output Flags (mutually exclusive):
+  -X, --extended           Enable extended output
+  -M, --markdown           Enable markdown table output
+  -O, --orgtbl             Enable org-mode table output
+  -S, --shell              Enable shell evaluable ouput
+  -Y, --yaml               Enable yaml output
+  -C, --csv                Enable CSV output
+  -A, --ascii              Default output mode, ascii tabular
+
+Sort Mode Flags (mutually exclusive):
+  -a, --sort-age           sort according to age (duration) string
+  -D, --sort-desc          Sort in descending order (default: ascending)
+  -i, --sort-numeric       sort according to string numerical value
+  -t, --sort-time          sort according to time string
+
+Other Flags:
+  -d, --debug              Enable debugging
+  -h, --help               help for tablizer
+  -m, --man                Display manual page
+  -v, --version            Print program version
+
+
+`

lib/common.go

@@ -20,7 +20,6 @@ package lib
 // contains a whole parsed table
 type Tabdata struct {
 	maxwidthHeader int      // longest header
-	maxwidthPerCol []int    // max width per column
 	columns        int      // count
 	headers        []string // [ "ID", "NAME", ...]
 	entries        [][]string

lib/helpers.go

@@ -155,17 +155,10 @@ func trimRow(row []string) []string {
 func colorizeData(c cfg.Config, output string) string {
 	if len(c.Pattern) > 0 && !c.NoColor && color.IsConsole(os.Stdout) {
 		r := regexp.MustCompile("(" + c.Pattern + ")")
-		return r.ReplaceAllString(output, "<bg="+c.MatchBG+";fg="+c.MatchFG+">$1</>")
+		return r.ReplaceAllStringFunc(output, func(in string) string {
+			return c.ColorStyle.Sprint(in)
+		})
 	} else {
 		return output
 	}
 }
-
-func isTerminal(f *os.File) bool {
-	o, _ := f.Stat()
-	if (o.Mode() & os.ModeCharDevice) == os.ModeCharDevice {
-		return true
-	} else {
-		return false
-	}
-}

lib/helpers_test.go

@@ -48,11 +48,6 @@ func TestContains(t *testing.T) {
 func TestPrepareColumns(t *testing.T) {
 	data := Tabdata{
 		maxwidthHeader: 5,
-		maxwidthPerCol: []int{
-			5,
-			5,
-			8,
-		},
 		columns:        3,
 		headers: []string{
 			"ONE", "TWO", "THREE",

lib/io.go

@@ -19,50 +19,39 @@ package lib
 
 import (
 	"errors"
-	"github.com/gookit/color"
 	"github.com/tlinden/tablizer/cfg"
 	"io"
 	"os"
 )
 
-func ProcessFiles(c cfg.Config, args []string) error {
+func ProcessFiles(c *cfg.Config, args []string) error {
-	fds, pattern, err := determineIO(&c, args)
+	fds, pattern, err := determineIO(c, args)
 
 	if err != nil {
 		return err
 	}
 
-	determineColormode(&c)
+	if err := c.PreparePattern(pattern); err != nil {
+		return err
+	}
 
 	for _, fd := range fds {
-		data, err := parseFile(c, fd, pattern)
+		data, err := Parse(*c, fd)
 		if err != nil {
 			return err
 		}
 
-		err = PrepareColumns(&c, &data)
+		err = PrepareColumns(c, &data)
 		if err != nil {
 			return err
 		}
 
-		printData(os.Stdout, c, &data)
+		printData(os.Stdout, *c, &data)
 	}
 
 	return nil
 }
 
-// find supported color mode, modifies config based on constants
-func determineColormode(c *cfg.Config) {
-	if !isTerminal(os.Stdout) {
-		color.Disable()
-	} else {
-		level := color.TermColorLevel()
-		colors := cfg.Colors()
-		c.MatchFG = colors[level]["fg"]
-		c.MatchBG = colors[level]["bg"]
-	}
-}
-
 func determineIO(c *cfg.Config, args []string) ([]io.Reader, string, error) {
 	var pattern string
 	var fds []io.Reader

lib/parser.go

@@ -19,6 +19,7 @@ package lib
 
 import (
 	"bufio"
+	"encoding/csv"
 	"errors"
 	"fmt"
 	"github.com/alecthomas/repr"
@@ -28,20 +29,84 @@ import (
 	"strings"
 )
 
+/*
+   Parser switch
+*/
+func Parse(c cfg.Config, input io.Reader) (Tabdata, error) {
+	if len(c.Separator) == 1 {
+		return parseCSV(c, input)
+	}
+
+	return parseTabular(c, input)
+}
+
+/*
+   Parse CSV input.
+*/
+func parseCSV(c cfg.Config, input io.Reader) (Tabdata, error) {
+	var content io.Reader = input
+	data := Tabdata{}
+
+	if len(c.Pattern) > 0 {
+		scanner := bufio.NewScanner(input)
+		lines := []string{}
+		hadFirst := false
+		for scanner.Scan() {
+			line := strings.TrimSpace(scanner.Text())
+			if hadFirst {
+				// don't match 1st line, it's the header
+				if c.PatternR.MatchString(line) == c.InvertMatch {
+					// by default  -v is false, so if a  line does NOT
+					// match the pattern, we will ignore it. However,
+					// if the user specified -v, the matching is inverted,
+					// so we ignore all lines, which DO match.
+					continue
+				}
+			}
+			lines = append(lines, line)
+			hadFirst = true
+		}
+		content = strings.NewReader(strings.Join(lines, "\n"))
+	}
+
+	csvreader := csv.NewReader(content)
+	csvreader.Comma = rune(c.Separator[0])
+
+	records, err := csvreader.ReadAll()
+	if err != nil {
+		return data, errors.Unwrap(fmt.Errorf("Could not parse CSV input: %w", err))
+	}
+
+	if len(records) >= 1 {
+		data.headers = records[0]
+		data.columns = len(records)
+
+		for _, head := range data.headers {
+			// register widest header field
+			headerlen := len(head)
+			if headerlen > data.maxwidthHeader {
+				data.maxwidthHeader = headerlen
+			}
+		}
+
+		if len(records) > 1 {
+			data.entries = records[1:]
+		}
+	}
+
+	return data, nil
+}
+
 /*
    Parse tabular input.
 */
-func parseFile(c cfg.Config, input io.Reader, pattern string) (Tabdata, error) {
+func parseTabular(c cfg.Config, input io.Reader) (Tabdata, error) {
 	data := Tabdata{}
 
 	var scanner *bufio.Scanner
 
 	hadFirst := false
 	separate := regexp.MustCompile(c.Separator)
-	patternR, err := regexp.Compile(pattern)
-	if err != nil {
-		return data, errors.Unwrap(fmt.Errorf("Regexp pattern %s is invalid: %w", pattern, err))
-	}
 
 	scanner = bufio.NewScanner(input)
 
@@ -76,8 +141,8 @@ func parseFile(c cfg.Config, input io.Reader, pattern string) (Tabdata, error) {
 			}
 		} else {
 			// data processing
-			if len(pattern) > 0 {
+			if len(c.Pattern) > 0 {
-				if patternR.MatchString(line) == c.InvertMatch {
+				if c.PatternR.MatchString(line) == c.InvertMatch {
 					// by default  -v is false, so if a  line does NOT
 					// match the pattern, we will ignore it. However,
 					// if the user specified -v, the matching is inverted,
@@ -89,16 +154,6 @@ func parseFile(c cfg.Config, input io.Reader, pattern string) (Tabdata, error) {
 			idx := 0 // we cannot use the header index, because we could exclude columns
 			values := []string{}
 			for _, part := range parts {
-				width := len(strings.TrimSpace(part))
-
-				if len(data.maxwidthPerCol)-1 < idx {
-					data.maxwidthPerCol = append(data.maxwidthPerCol, width)
-				} else {
-					if width > data.maxwidthPerCol[idx] {
-						data.maxwidthPerCol[idx] = width
-					}
-				}
-
 				// if Debug {
 				// 	fmt.Printf("<%s> ", value)
 				// }

lib/parser_test.go

@@ -25,40 +25,58 @@ import (
 	"testing"
 )
 
+var input = []struct {
+	name      string
+	text      string
+	separator string
+}{
+	{
+		name:      "tabular-data",
+		separator: cfg.DefaultSeparator,
+		text: `
+ONE    TWO    THREE  
+asd    igig   cxxxncnc  
+19191  EDD 1  X`,
+	},
+	{
+		name:      "csv-data",
+		separator: ",",
+		text: `
+ONE,TWO,THREE
+asd,igig,cxxxncnc
+19191,"EDD 1",X`,
+	},
+}
+
 func TestParser(t *testing.T) {
 	data := Tabdata{
 		maxwidthHeader: 5,
-		maxwidthPerCol: []int{
-			5, 5, 8,
-		},
 		columns:        3,
 		headers: []string{
 			"ONE", "TWO", "THREE",
 		},
 		entries: [][]string{
-			{
+			{"asd", "igig", "cxxxncnc"},
-				"asd", "igig", "cxxxncnc",
+			{"19191", "EDD 1", "X"},
-			},
-			{
-				"19191", "EDD 1", "X",
-			},
 		},
 	}
 
-	table := `ONE    TWO    THREE  
+	for _, in := range input {
-asd    igig   cxxxncnc  
+		testname := fmt.Sprintf("parse-%s", in.name)
-19191  EDD 1  X`
+		t.Run(testname, func(t *testing.T) {
-
+			readFd := strings.NewReader(strings.TrimSpace(in.text))
-	readFd := strings.NewReader(table)
+			c := cfg.Config{Separator: in.separator}
-	c := cfg.Config{Separator: cfg.DefaultSeparator}
+			gotdata, err := Parse(c, readFd)
-	gotdata, err := parseFile(c, readFd, "")
 
 			if err != nil {
 				t.Errorf("Parser returned error: %s\nData processed so far: %+v", err, gotdata)
 			}
 
 			if !reflect.DeepEqual(data, gotdata) {
-		t.Errorf("Parser returned invalid data, Regex: %s\nExp: %+v\nGot: %+v\n", c.Separator, data, gotdata)
+				t.Errorf("Parser returned invalid data\nExp: %+v\nGot: %+v\n",
+					data, gotdata)
+			}
+		})
 	}
 }
 
@@ -71,48 +89,37 @@ func TestParserPatternmatching(t *testing.T) {
 	}{
 		{
 			entries: [][]string{
-				{
+				{"asd", "igig", "cxxxncnc"},
-					"asd", "igig", "cxxxncnc",
-				},
 			},
 			pattern: "ig",
 			invert:  false,
 		},
 		{
 			entries: [][]string{
-				{
+				{"19191", "EDD 1", "X"},
-					"19191", "EDD 1", "X",
-				},
 			},
 			pattern: "ig",
 			invert:  true,
 		},
-		{
-			entries: [][]string{
-				{
-					"asd", "igig", "cxxxncnc",
-				},
-			},
-			pattern: "[a-z",
-			want:    true,
-		},
 	}
 
-	table := `ONE    TWO    THREE  
+	for _, in := range input {
-asd    igig   cxxxncnc  
-19191  EDD 1  X`
-
 		for _, tt := range tests {
-		testname := fmt.Sprintf("parse-with-pattern-%s-inverted-%t", tt.pattern, tt.invert)
+			testname := fmt.Sprintf("parse-%s-with-pattern-%s-inverted-%t",
+				in.name, tt.pattern, tt.invert)
 			t.Run(testname, func(t *testing.T) {
-			c := cfg.Config{InvertMatch: tt.invert, Pattern: tt.pattern, Separator: cfg.DefaultSeparator}
+				c := cfg.Config{InvertMatch: tt.invert, Pattern: tt.pattern,
+					Separator: in.separator}
 
-			readFd := strings.NewReader(table)
+				_ = c.PreparePattern(tt.pattern)
-			gotdata, err := parseFile(c, readFd, tt.pattern)
+
+				readFd := strings.NewReader(strings.TrimSpace(in.text))
+				gotdata, err := Parse(c, readFd)
 
 				if err != nil {
 					if !tt.want {
-					t.Errorf("Parser returned error: %s\nData processed so far: %+v", err, gotdata)
+						t.Errorf("Parser returned error: %s\nData processed so far: %+v",
+							err, gotdata)
 					}
 				} else {
 					if !reflect.DeepEqual(tt.entries, gotdata.entries) {
@@ -123,34 +130,29 @@ asd    igig   cxxxncnc
 			})
 		}
 	}
+}
 
 func TestParserIncompleteRows(t *testing.T) {
 	data := Tabdata{
 		maxwidthHeader: 5,
-		maxwidthPerCol: []int{
-			5, 5, 1,
-		},
 		columns:        3,
 		headers: []string{
 			"ONE", "TWO", "THREE",
 		},
 		entries: [][]string{
-			{
+			{"asd", "igig", ""},
-				"asd", "igig", "",
+			{"19191", "EDD 1", "X"},
-			},
-			{
-				"19191", "EDD 1", "X",
-			},
 		},
 	}
 
-	table := `ONE    TWO    THREE  
+	table := `
+ONE    TWO    THREE  
 asd    igig
 19191  EDD 1  X`
 
-	readFd := strings.NewReader(table)
+	readFd := strings.NewReader(strings.TrimSpace(table))
 	c := cfg.Config{Separator: cfg.DefaultSeparator}
-	gotdata, err := parseFile(c, readFd, "")
+	gotdata, err := Parse(c, readFd)
 
 	if err != nil {
 		t.Errorf("Parser returned error: %s\nData processed so far: %+v", err, gotdata)

lib/printer.go

@@ -18,6 +18,7 @@ along with this program. If not, see <http://www.gnu.org/licenses/>.
 package lib
 
 import (
+	"encoding/csv"
 	"fmt"
 	"github.com/gookit/color"
 	"github.com/olekukonko/tablewriter"
@@ -43,21 +44,24 @@ func printData(w io.Writer, c cfg.Config, data *Tabdata) {
 	sortTable(c, data)
 
 	switch c.OutputMode {
-	case "extended":
+	case cfg.Extended:
 		printExtendedData(w, c, data)
-	case "ascii":
+	case cfg.Ascii:
 		printAsciiData(w, c, data)
-	case "orgtbl":
+	case cfg.Orgtbl:
 		printOrgmodeData(w, c, data)
-	case "markdown":
+	case cfg.Markdown:
 		printMarkdownData(w, c, data)
-	case "shell":
+	case cfg.Shell:
 		printShellData(w, c, data)
-	case "yaml":
+	case cfg.Yaml:
 		printYamlData(w, c, data)
+	case cfg.CSV:
+		printCSVData(w, c, data)
 	default:
 		printAsciiData(w, c, data)
 	}
+
 }
 
 func output(w io.Writer, str string) {
@@ -185,7 +189,7 @@ func printShellData(w io.Writer, c cfg.Config, data *Tabdata) {
 		}
 	}
 
-	// no colrization here
+	// no colorization here
 	output(w, out)
 }
 
@@ -224,3 +228,23 @@ func printYamlData(w io.Writer, c cfg.Config, data *Tabdata) {
 
 	output(w, string(yamlstr))
 }
+
+func printCSVData(w io.Writer, c cfg.Config, data *Tabdata) {
+	csvout := csv.NewWriter(w)
+
+	if err := csvout.Write(data.headers); err != nil {
+		log.Fatalln("error writing record to csv:", err)
+	}
+
+	for _, entry := range data.entries {
+		if err := csvout.Write(entry); err != nil {
+			log.Fatalln("error writing record to csv:", err)
+		}
+	}
+
+	csvout.Flush()
+
+	if err := csvout.Error(); err != nil {
+		log.Fatal(err)
+	}
+}

lib/printer_test.go

@@ -29,12 +29,6 @@ import (
 func newData() Tabdata {
 	return Tabdata{
 		maxwidthHeader: 8,
-		maxwidthPerCol: []int{
-			5,
-			9,
-			3,
-			26,
-		},
 		columns:        4,
 		headers: []string{
 			"NAME",
@@ -72,24 +66,33 @@ var tests = []struct {
 	column    int    // sort by this column, 0 == default first or NO Sort
 	desc      bool   // sort in descending order, default == ascending
 	nonum     bool   // hide numbering
-	mode      string // shell, orgtbl, etc. empty == default: ascii
+	mode      int    // shell, orgtbl, etc. empty == default: ascii
 	usecol    []int  // columns to display, empty == display all
 	usecolstr string // for testname, must match usecol
 	expect    string // rendered output we expect
 }{
 	// --------------------- Default settings mode tests ``
 	{
-		mode: "ascii",
+		mode: cfg.Ascii,
 		name: "default",
 		expect: `
 NAME(1)	DURATION(2)	COUNT(3)	WHEN(4)                    
 beta   	1d10h5m1s  	33      	3/1/2014                  	
 alpha  	4h35m      	170     	2013-Feb-03               	
 ceta   	33d12h     	9       	06/Jan/2008 15:04:05 -0700`,
+	},
+	{
+		mode: cfg.CSV,
+		name: "csv",
+		expect: `
+NAME,DURATION,COUNT,WHEN
+beta,1d10h5m1s,33,3/1/2014
+alpha,4h35m,170,2013-Feb-03
+ceta,33d12h,9,06/Jan/2008 15:04:05 -0700`,
 	},
 	{
 		name: "default",
-		mode: "orgtbl",
+		mode: cfg.Orgtbl,
 		expect: `
 +---------+-------------+----------+----------------------------+
 | NAME(1) | DURATION(2) | COUNT(3) |          WHEN(4)           |
@@ -101,7 +104,7 @@ ceta   	33d12h     	9       	06/Jan/2008 15:04:05 -0700`,
 	},
 	{
 		name: "default",
-		mode: "markdown",
+		mode: cfg.Markdown,
 		expect: `
 | NAME(1) | DURATION(2) | COUNT(3) |          WHEN(4)           |
 |---------|-------------|----------|----------------------------|
@@ -111,7 +114,7 @@ ceta   	33d12h     	9       	06/Jan/2008 15:04:05 -0700`,
 	},
 	{
 		name:  "default",
-		mode:  "shell",
+		mode:  cfg.Shell,
 		nonum: true,
 		expect: `
 NAME="beta" DURATION="1d10h5m1s" COUNT="33" WHEN="3/1/2014"
@@ -120,7 +123,7 @@ NAME="ceta" DURATION="33d12h" COUNT="9" WHEN="06/Jan/2008 15:04:05 -0700"`,
 	},
 	{
 		name:  "default",
-		mode:  "yaml",
+		mode:  cfg.Yaml,
 		nonum: true,
 		expect: `
 entries:
@@ -139,7 +142,7 @@ entries:
 	},
 	{
 		name: "default",
-		mode: "extended",
+		mode: cfg.Extended,
 		expect: `
     NAME(1): beta
 DURATION(2): 1d10h5m1s
@@ -248,7 +251,7 @@ DURATION(2)	WHEN(4)
 
 func TestPrinter(t *testing.T) {
 	for _, tt := range tests {
-		testname := fmt.Sprintf("print-sortcol-%d-desc-%t-sortby-%s-mode-%s-usecolumns-%s",
+		testname := fmt.Sprintf("print-sortcol-%d-desc-%t-sortby-%s-mode-%d-usecolumns-%s",
 			tt.column, tt.desc, tt.sortby, tt.mode, tt.usecolstr)
 		t.Run(testname, func(t *testing.T) {
 			// replaces os.Stdout, but we ignore it
@@ -265,6 +268,8 @@ func TestPrinter(t *testing.T) {
 				NoColor:        true,
 			}
 
+			c.ApplyDefaults()
+
 			// the test checks the len!
 			if len(tt.usecol) > 0 {
 				c.Columns = "yes"

tablizer.1

@@ -133,7 +133,7 @@
 .\" ========================================================================
 .\"
 .IX Title "TABLIZER 1"
-.TH TABLIZER 1 "2022-10-16" "1" "User Commands"
+.TH TABLIZER 1 "2022-10-23" "1" "User Commands"
 .\" For nroff, turn off justification.  Always turn off hyphenation; it makes
 .\" way too many mistakes in technical documents.
 .if n .ad l
@@ -146,24 +146,33 @@ tablizer \- Manipulate tabular output of other programs
 \&    Usage:
 \&      tablizer [regex] [file, ...] [flags]
 \&    
-\&    Flags:
+\&    Operational Flags:
 \&      \-c, \-\-columns string     Only show the speficied columns (separated by ,)
-\&      \-d, \-\-debug              Enable debugging
-\&      \-h, \-\-help               help for tablizer
 \&      \-v, \-\-invert\-match       select non\-matching rows
-\&      \-m, \-\-man                Display manual page
 \&      \-n, \-\-no\-numbering       Disable header numbering
 \&      \-N, \-\-no\-color           Disable pattern highlighting
-\&      \-o, \-\-output string      Output mode \- one of: orgtbl, markdown, extended, yaml, ascii(default)
+\&      \-s, \-\-separator string   Custom field separator
+\&      \-k, \-\-sort\-by int        Sort by column (default: 1)
+\&
+\&    Output Flags (mutually exclusive):
 \&      \-X, \-\-extended           Enable extended output
 \&      \-M, \-\-markdown           Enable markdown table output
 \&      \-O, \-\-orgtbl             Enable org\-mode table output
-\&      \-s, \-\-separator string   Custom field separator
+\&      \-S, \-\-shell              Enable shell evaluable ouput
+\&      \-Y, \-\-yaml               Enable yaml output
+\&      \-C, \-\-csv                Enable CSV output
+\&      \-A, \-\-ascii              Default output mode, ascii tabular
+\&
+\&    Sort Mode Flags (mutually exclusive):
 \&      \-a, \-\-sort\-age           sort according to age (duration) string
-\&      \-k, \-\-sort\-by int        Sort by column (default: 1)
 \&      \-D, \-\-sort\-desc          Sort in descending order (default: ascending)
 \&      \-i, \-\-sort\-numeric       sort according to string numerical value
 \&      \-t, \-\-sort\-time          sort according to time string
+\&
+\&    Other Flags:
+\&      \-d, \-\-debug              Enable debugging
+\&      \-h, \-\-help               help for tablizer
+\&      \-m, \-\-man                Display manual page
 \&      \-v, \-\-version            Print program version
 .Ve
 .SH "DESCRIPTION"
@@ -345,8 +354,22 @@ You can use this in an eval loop.
 .PP
 Beside normal  ascii mode  (the default) and  extended mode  there are
 more output modes available: \fBorgtbl\fR  which prints an Emacs org-mode
-table and \fBmarkdown\fR which prints a Markdown table and \fByaml\fR, which
+table and  \fBmarkdown\fR which prints  a Markdown table,  \fByaml\fR, which
-prints yaml encoding.
+prints  yaml encoding  and \s-1CSV\s0  mode, which  prints a  comma separated
+value file.
+.SS "\s-1ENVIRONMENT VARIABLES\s0"
+.IX Subsection "ENVIRONMENT VARIABLES"
+\&\fBtablizer\fR supports  certain environment variables which  use can use
+to  influence   program  behavior.   Commandline  flags   have  always
+precedence over environment variables.
+.IP "<T_NO_HEADER_NUMBERING> \- disable numbering of header fields, like \fB\-n\fR." 4
+.IX Item "<T_NO_HEADER_NUMBERING> - disable numbering of header fields, like -n."
+.PD 0
+.IP "<T_COLUMNS> \- comma separated list of columns to output, like \fB\-c\fR" 4
+.IX Item "<T_COLUMNS> - comma separated list of columns to output, like -c"
+.IP "<\s-1NO_COLORS\s0> \- disable colorization of matches, like \fB\-N\fR" 4
+.IX Item "<NO_COLORS> - disable colorization of matches, like -N"
+.PD
 .SH "BUGS"
 .IX Header "BUGS"
 In order to report a bug, unexpected behavior, feature requests

tablizer.pod

@@ -7,24 +7,33 @@ tablizer - Manipulate tabular output of other programs
     Usage:
       tablizer [regex] [file, ...] [flags]
     
-    Flags:
+    Operational Flags:
       -c, --columns string     Only show the speficied columns (separated by ,)
-      -d, --debug              Enable debugging
-      -h, --help               help for tablizer
       -v, --invert-match       select non-matching rows
-      -m, --man                Display manual page
       -n, --no-numbering       Disable header numbering
       -N, --no-color           Disable pattern highlighting
-      -o, --output string      Output mode - one of: orgtbl, markdown, extended, yaml, ascii(default)
+      -s, --separator string   Custom field separator
+      -k, --sort-by int        Sort by column (default: 1)
+
+    Output Flags (mutually exclusive):
       -X, --extended           Enable extended output
       -M, --markdown           Enable markdown table output
       -O, --orgtbl             Enable org-mode table output
-      -s, --separator string   Custom field separator
+      -S, --shell              Enable shell evaluable ouput
+      -Y, --yaml               Enable yaml output
+      -C, --csv                Enable CSV output
+      -A, --ascii              Default output mode, ascii tabular
+
+    Sort Mode Flags (mutually exclusive):
       -a, --sort-age           sort according to age (duration) string
-      -k, --sort-by int        Sort by column (default: 1)
       -D, --sort-desc          Sort in descending order (default: ascending)
       -i, --sort-numeric       sort according to string numerical value
       -t, --sort-time          sort according to time string
+
+    Other Flags:
+      -d, --debug              Enable debugging
+      -h, --help               help for tablizer
+      -m, --man                Display manual page
       -v, --version            Print program version
 
 
@@ -198,8 +207,26 @@ You can use this in an eval loop.
 
 Beside normal  ascii mode  (the default) and  extended mode  there are
 more output modes available: B<orgtbl>  which prints an Emacs org-mode
-table and B<markdown> which prints a Markdown table and B<yaml>, which
+table and  B<markdown> which prints  a Markdown table,  B<yaml>, which
-prints yaml encoding.
+prints  yaml encoding  and CSV  mode, which  prints a  comma separated
+value file.
+
+=head2 ENVIRONMENT VARIABLES
+
+B<tablizer> supports  certain environment variables which  use can use
+to  influence   program  behavior.   Commandline  flags   have  always
+precedence over environment variables.
+
+=over
+
+=item <T_NO_HEADER_NUMBERING> - disable numbering of header fields, like B<-n>.
+
+=item <T_COLUMNS> - comma separated list of columns to output, like B<-c>
+
+=item <NO_COLORS> - disable colorization of matches, like B<-N>
+
+=back
+
 
 =head1 BUGS