Merge pull request #276 from olekukonko/runewidth

Improve EastAsianWidth Handling with Custom Condition

Author: olekukonko

MIGRATION.md

@@ -1914,7 +1914,7 @@ func main() {
     - **Direct ANSI Codes**: Embed codes (e.g., `\033[32m` for green) in strings for manual control (`zoo.go:convertCellsToStrings`).
     - **tw.Formatter**: Implement `Format() string` on custom types to control cell output, including colors (`tw/types.go:Formatter`).
     - **tw.CellFilter**: Use `Config.<Section>.Filter.Global` or `PerColumn` to apply transformations like coloring dynamically (`tw/cell.go:CellFilter`).
-- **Width Handling**: `tw.DisplayWidth()` correctly calculates display width of ANSI-coded strings, ignoring escape sequences (`tw/fn.go:DisplayWidth`).
+- **Width Handling**: `twdw.Width()` correctly calculates display width of ANSI-coded strings, ignoring escape sequences (`tw/fn.go:DisplayWidth`).
 - **No Built-In Color Presets**: Unlike v0.0.5’s potential `tablewriter.Colors`, v1.0.x requires manual ANSI code management or external libraries for color constants.
 
 **Migration Tips**:
@@ -1928,7 +1928,7 @@ func main() {
 **Potential Pitfalls**:
 - **Terminal Support**: Some terminals may not support ANSI codes, causing artifacts; test in your environment or provide a non-colored fallback.
 - **Filter Overlap**: Combining `tw.CellFilter` with `AutoFormat` or other transformations can lead to unexpected results; prioritize filters for coloring (`zoo.go`).
-- **Width Miscalculation**: Incorrect ANSI code handling (e.g., missing `Reset`) can skew width calculations; use `tw.DisplayWidth` (`tw/fn.go`).
+- **Width Miscalculation**: Incorrect ANSI code handling (e.g., missing `Reset`) can skew width calculations; use `twdw.Width` (`tw/fn.go`).
 - **Streaming Consistency**: In streaming mode, ensure color codes are applied consistently across rows to avoid visual discrepancies (`stream.go`).
 - **Performance**: Applying filters to large datasets may add overhead; optimize filter logic for efficiency (`zoo.go`).
 
@@ -2818,7 +2818,7 @@ func main() {
 **Notes**:
 - **Configuration**: Uses `tw.CellFilter` for per-column coloring, embedding ANSI codes (`tw/cell.go`).
 - **Migration from v0.0.5**: Replaces `SetColumnColor` with dynamic filters (`tablewriter.go`).
-- **Key Features**: Flexible color application; `tw.DisplayWidth` handles ANSI codes correctly (`tw/fn.go`).
+- **Key Features**: Flexible color application; `twdw.Width` handles ANSI codes correctly (`tw/fn.go`).
 - **Best Practices**: Test in ANSI-compatible terminals; use constants for code clarity.
 - **Potential Issues**: Non-ANSI terminals may show artifacts; provide fallbacks (`tw/fn.go`).
 
@@ -3005,7 +3005,7 @@ This section addresses common migration issues with detailed solutions, covering
 | Merging not working                       | **Cause**: Streaming mode or mismatched data. **Solution**: Use batch mode for vertical/hierarchical merging; ensure identical content (`zoo.go`). |
 | Alignment ignored                         | **Cause**: `PerColumn` overrides `Global`. **Solution**: Check `Config.Section.Alignment.PerColumn` settings or `ConfigBuilder` calls (`tw/cell.go`). |
 | Padding affects widths                    | **Cause**: Padding included in `Config.Widths`. **Solution**: Adjust `Config.Widths` to account for `tw.CellPadding` (`zoo.go`). |
-| Colors not rendering                      | **Cause**: Non-ANSI terminal or incorrect codes. **Solution**: Test in ANSI-compatible terminal; use `tw.DisplayWidth` (`tw/fn.go`). |
+| Colors not rendering                      | **Cause**: Non-ANSI terminal or incorrect codes. **Solution**: Test in ANSI-compatible terminal; use `twdw.Width` (`tw/fn.go`). |
 | Caption missing                           | **Cause**: `Close()` not called in streaming or incorrect `Spot`. **Solution**: Ensure `Close()`; verify `tw.Caption.Spot` (`tablewriter.go`). |
 | Filters not applied                       | **Cause**: Incorrect `PerColumn` indexing or nil filters. **Solution**: Set filters correctly; test with sample data (`tw/cell.go`). |
 | Stringer cache overhead                   | **Cause**: Large datasets with diverse types. **Solution**: Disable `WithStringerCache` for small tables if not using `WithStringer` or if types vary greatly (`tablewriter.go`). |

deprecated.go

@@ -1,6 +1,8 @@
 package tablewriter
 
-import "github.com/olekukonko/tablewriter/tw"
+import (
+	"github.com/olekukonko/tablewriter/tw"
+)
 
 // WithBorders configures the table's border settings by updating the renderer's border configuration.
 // This function is deprecated and will be removed in a future version.

option.go

@@ -1,7 +1,9 @@
 package tablewriter
 
 import (
+	"github.com/mattn/go-runewidth"
 	"github.com/olekukonko/ll"
+	"github.com/olekukonko/tablewriter/pkg/twwidth"
 	"github.com/olekukonko/tablewriter/tw"
 	"reflect"
 )
@@ -613,6 +615,31 @@ func WithRendition(rendition tw.Rendition) Option {
 	}
 }
 
+// WithEastAsian configures the global East Asian width calculation setting.
+//   - enable=true: Enables East Asian width calculations. CJK and ambiguous characters
+//     are typically measured as double width.
+//   - enable=false: Disables East Asian width calculations. Characters are generally
+//     measured as single width, subject to Unicode standards.
+//
+// This setting affects all subsequent display width calculations using the twdw package.
+func WithEastAsian(enable bool) Option {
+	return func(target *Table) {
+		twwidth.SetEastAsian(enable)
+	}
+}
+
+// WithCondition provides a way to set a custom global runewidth.Condition
+// that will be used for all subsequent display width calculations by the twwidth (twdw) package.
+//
+// The runewidth.Condition object allows for more fine-grained control over how rune widths
+// are determined, beyond just toggling EastAsianWidth. This could include settings for
+// ambiguous width characters or other future properties of runewidth.Condition.
+func WithCondition(condition *runewidth.Condition) Option {
+	return func(target *Table) {
+		twwidth.SetCondition(condition)
+	}
+}
+
 // WithSymbols sets the symbols used for drawing table borders and separators.
 // The symbols are applied to the table's renderer configuration, if a renderer is set.
 // If no renderer is set (target.renderer is nil), this option has no effect. .

pkg/twwarp/wrap.go

@@ -8,12 +8,13 @@
 package twwarp
 
 import (
-	"github.com/rivo/uniseg"
 	"math"
 	"strings"
 	"unicode"
 
-	"github.com/mattn/go-runewidth"
+	"github.com/olekukonko/tablewriter/pkg/twwidth" // IMPORT YOUR NEW PACKAGE
+	"github.com/rivo/uniseg"
+	// "github.com/mattn/go-runewidth" // This can be removed if all direct uses are gone
 )
 
 const (
@@ -59,7 +60,8 @@ func WrapString(s string, lim int) ([]string, int) {
 	var lines []string
 	max := 0
 	for _, v := range words {
-		max = runewidth.StringWidth(v)
+		// max = runewidth.StringWidth(v) // OLD
+		max = twwidth.Width(v) // NEW: Use twdw.Width
 		if max > lim {
 			lim = max
 		}
@@ -82,12 +84,13 @@ func WrapStringWithSpaces(s string, lim int) ([]string, int) {
 		return []string{""}, lim
 	}
 	if strings.TrimSpace(s) == "" { // All spaces
-		if runewidth.StringWidth(s) <= lim {
-			return []string{s}, runewidth.StringWidth(s)
+		// if runewidth.StringWidth(s) <= lim { // OLD
+		if twwidth.Width(s) <= lim { // NEW: Use twdw.Width
+			// return []string{s}, runewidth.StringWidth(s) // OLD
+			return []string{s}, twwidth.Width(s) // NEW: Use twdw.Width
 		}
 		// For very long all-space strings, "wrap" by truncating to the limit.
 		if lim > 0 {
-			// Use our new helper function to get a substring of the correct display width
 			substring, _ := stringToDisplayWidth(s, lim)
 			return []string{substring}, lim
 		}
@@ -96,7 +99,6 @@ func WrapStringWithSpaces(s string, lim int) ([]string, int) {
 
 	var leadingSpaces, trailingSpaces, coreContent string
 	firstNonSpace := strings.IndexFunc(s, func(r rune) bool { return !unicode.IsSpace(r) })
-	// firstNonSpace will not be -1 due to TrimSpace check above.
 	leadingSpaces = s[:firstNonSpace]
 	lastNonSpace := strings.LastIndexFunc(s, func(r rune) bool { return !unicode.IsSpace(r) })
 	trailingSpaces = s[lastNonSpace+1:]
@@ -116,7 +118,8 @@ func WrapStringWithSpaces(s string, lim int) ([]string, int) {
 
 	maxCoreWordWidth := 0
 	for _, v := range words {
-		w := runewidth.StringWidth(v)
+		// w := runewidth.StringWidth(v) // OLD
+		w := twwidth.Width(v) // NEW: Use twdw.Width
 		if w > maxCoreWordWidth {
 			maxCoreWordWidth = w
 		}
@@ -153,15 +156,14 @@ func stringToDisplayWidth(s string, targetWidth int) (substring string, actualWi
 	g := uniseg.NewGraphemes(s)
 	for g.Next() {
 		grapheme := g.Str()
-		graphemeWidth := runewidth.StringWidth(grapheme) // Get width of the current grapheme cluster
+		// graphemeWidth := runewidth.StringWidth(grapheme) // OLD
+		graphemeWidth := twwidth.Width(grapheme) // NEW: Use twdw.Width
 
 		if currentWidth+graphemeWidth > targetWidth {
-			// Adding this grapheme would exceed the target width
 			break
 		}
 
 		currentWidth += graphemeWidth
-		// Get the end byte position of the current grapheme cluster
 		_, e := g.Positions()
 		endIndex = e
 	}
@@ -186,14 +188,15 @@ func WrapWords(words []string, spc, lim, pen int) [][]string {
 	}
 	lengths := make([]int, n)
 	for i := 0; i < n; i++ {
-		lengths[i] = runewidth.StringWidth(words[i])
+		// lengths[i] = runewidth.StringWidth(words[i]) // OLD
+		lengths[i] = twwidth.Width(words[i]) // NEW: Use twdw.Width
 	}
 	nbrk := make([]int, n)
 	cost := make([]int, n)
 	for i := range cost {
 		cost[i] = math.MaxInt32
 	}
-	remainderLen := lengths[n-1]
+	remainderLen := lengths[n-1] // Uses updated lengths
 	for i := n - 1; i >= 0; i-- {
 		if i < n-1 {
 			remainderLen += spc + lengths[i]

pkg/twwarp/wrap_test.go

@@ -10,6 +10,7 @@ package twwarp
 import (
 	"bytes"
 	"fmt"
+	"github.com/olekukonko/tablewriter/pkg/twwidth"
 	"github.com/olekukonko/tablewriter/tw"
 	"os"
 	"reflect"
@@ -72,14 +73,14 @@ func TestDisplayWidth(t *testing.T) {
 	if runewidth.IsEastAsian() {
 		want = 14
 	}
-	if n := tw.DisplayWidth(input); n != want {
+	if n := twwidth.Width(input); n != want {
 		t.Errorf("Wants: %d Got: %d", want, n)
 	}
 	input = "\033[43;30m" + input + "\033[00m"
-	checkEqual(t, tw.DisplayWidth(input), want)
+	checkEqual(t, twwidth.Width(input), want)
 
 	input = "\033]8;;idea://open/?file=/path/somefile.php&line=12\033\\some URL\033]8;;\033\\"
-	checkEqual(t, tw.DisplayWidth(input), 8)
+	checkEqual(t, twwidth.Width(input), 8)
 
 }