Merge pull request #4 from noborus/positions-public

Made Positions public
noborus · Mar 20, 2023 · 231c7c5 · 231c7c5
2 parents c9340fd + 9ce2c63
commit 231c7c5
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Showing 2 changed files with 41 additions and 13 deletions.
diff --git a/guesswidth.go b/guesswidth.go
@@ -32,6 +32,9 @@ type GuessWidth struct {
 	Header int
 	// limitSplit is the maximum number of columns to split.
 	LimitSplit int
+	// MinLines is the minimum number of lines to recognize as a separator.
+	// 1 if only the header, 2 or more if there is a blank in the body.
+	MinLines int
 	// TrimSpace is whether to trim the space in the value.
 	TrimSpace bool
 }
@@ -45,6 +48,7 @@ func NewReader(r io.Reader) *GuessWidth {
 		preCount:   0,
 		Header:     0,
 		LimitSplit: 0,
+		MinLines:   2,
 		TrimSpace:  true,
 	}
 	return g
@@ -78,7 +82,7 @@ func (g *GuessWidth) Scan(num int) {
 		g.preLines = append(g.preLines, string(buf))
 	}
 
-	g.pos = widthPositions(g.preLines, g.Header)
+	g.pos = Positions(g.preLines, g.Header, g.MinLines)
 
 	if g.LimitSplit > 0 {
 		if len(g.pos) > g.LimitSplit {
@@ -109,24 +113,27 @@ func (g *GuessWidth) Read() ([]string, error) {
 	return split(line, g.pos, g.TrimSpace), nil
 }
 
-// ToTable parses a slice of rows and returns a table.
+// ToTable parses a slice of lines and returns a table.
 func ToTable(lines []string, header int, trimSpace bool) [][]string {
-	pos := widthPositions(lines, header)
+	pos := Positions(lines, header, 2)
 	return toRows(lines, pos, trimSpace)
 }
 
-// ToTableN parses a slice of rows and returns a table, but limits the number of splits.
+// ToTableN parses a slice of lines and returns a table, but limits the number of splits.
 func ToTableN(lines []string, header int, numSplit int, trimSpace bool) [][]string {
-	pos := widthPositions(lines, header)
+	pos := Positions(lines, header, 2)
 	if len(pos) > numSplit {
 		pos = pos[:numSplit]
 	}
 	return toRows(lines, pos, trimSpace)
 }
 
-func widthPositions(lines []string, header int) []int {
+// Positions returns separator positions
+// from multiple lines and header line number.
+// Lines before the header line are ignored.
+func Positions(lines []string, header int, minLines int) []int {
 	var blanks []int
-	limit := 2
+
 	if header < 0 {
 		header = 0
 	}
@@ -140,7 +147,7 @@ func widthPositions(lines []string, header int) []int {
 		}
 		blanks = countBlanks(blanks, strings.TrimSuffix(line, " "))
 	}
-	return positions(blanks, limit)
+	return positions(blanks, minLines)
 }
 
 func separatorPosition(lr []rune, p int, pos []int, n int) int {
@@ -216,6 +223,7 @@ func split(line string, pos []int, trimSpace bool) []string {
 	return columns
 }
 
+// roRows returns rows separated by columns.
 func toRows(lines []string, pos []int, trimSpace bool) [][]string {
 	rows := make([][]string, 0, len(lines))
 	for _, line := range lines {
@@ -269,8 +277,8 @@ func countBlanks(blanks []int, line string) []int {
 }
 
 // Generates a list of separator positions from a blank slice.
-func positions(blanks []int, limit int) []int {
-	max := limit
+func positions(blanks []int, minLines int) []int {
+	max := minLines
 	p := 0
 	var pos []int
 	for n, v := range blanks {
@@ -279,7 +287,7 @@ func positions(blanks []int, limit int) []int {
 			p = n
 		}
 		if v == 0 {
-			max = limit
+			max = minLines
 			if p > 0 {
 				pos = append(pos, p)
 				p = 0

diff --git a/guesswidth_test.go b/guesswidth_test.go
@@ -16,6 +16,7 @@ func TestGuessWidth_ReadAll(t *testing.T) {
 		ScanNum    int
 		Header     int
 		LimitSplit int
+		MinLines   int
 		TrimSpace  bool
 	}
 	tests := []struct {
@@ -29,7 +30,8 @@ func TestGuessWidth_ReadAll(t *testing.T) {
 				reader: bufio.NewReader(strings.NewReader(`   PID TTY          TIME CMD
 302965 pts/3    00:00:11 zsh
 709737 pts/3    00:00:00 ps`)),
-				ScanNum: 100,
+				ScanNum:  100,
+				MinLines: 2,
 			},
 			want: [][]string{
 				{"   PID", " TTY     ", "     TIME", "CMD"},
@@ -44,7 +46,8 @@ func TestGuessWidth_ReadAll(t *testing.T) {
 root           1  0.0  0.0 168576 13788 ?        Ss   Mar11   0:49 /sbin/init splash
 noborus   703052  2.1  0.7 1184814400 230920 ?   Sl   10:03   0:45 /opt/google/chrome/chrome
 noborus   721971  0.0  0.0  13716  3524 pts/3    R+   10:39   0:00 ps aux`)),
-				ScanNum: 100,
+				ScanNum:  100,
+				MinLines: 2,
 			},
 			want: [][]string{
 				{"USER     ", "    PID", " %CPU", " %MEM", "    VSZ", "   RSS", " TTY     ", " STAT", " START  ", " TIME", "COMMAND"},
@@ -53,6 +56,22 @@ noborus   721971  0.0  0.0  13716  3524 pts/3    R+   10:39   0:00 ps aux`)),
 				{"noborus  ", " 721971", "  0.0", "  0.0", "  13716", "  3524", " pts/3   ", " R+  ", " 10:39  ", " 0:00", "ps aux"},
 			},
 		},
+		{
+			name: "ps limit",
+			fields: fields{
+				reader: bufio.NewReader(strings.NewReader(`   PID TTY          TIME CMD
+302965 pts/3    00:00:11 zsh
+709737 pts/3    00:00:00 ps`)),
+				ScanNum:    100,
+				MinLines:   2,
+				LimitSplit: 2,
+			},
+			want: [][]string{
+				{"   PID", " TTY     ", "    TIME CMD"},
+				{"302965", " pts/3   ", "00:00:11 zsh"},
+				{"709737", " pts/3   ", "00:00:00 ps"},
+			},
+		},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
@@ -64,6 +83,7 @@ noborus   721971  0.0  0.0  13716  3524 pts/3    R+   10:39   0:00 ps aux`)),
 				ScanNum:    tt.fields.ScanNum,
 				Header:     tt.fields.Header,
 				LimitSplit: tt.fields.LimitSplit,
+				MinLines:   tt.fields.MinLines,
 				TrimSpace:  tt.fields.TrimSpace,
 			}
 			if got := g.ReadAll(); !reflect.DeepEqual(got, tt.want) {