text: 256-colors support (#388)

Author: jedib0t

Makefile

@@ -1,41 +1,84 @@
-.PHONY: all profile test
+# Declare all phony targets (targets that don't create files)
+.PHONY: all bench cyclo default demo-colors demo-list demo-progress demo-table fmt help profile test test-race tools vet
 
+# ============================================================================
+# Main targets
+# ============================================================================
+
+## default: Run tests (default target)
 default: test
 
+## all: Run all checks: tests and benchmarks
 all: test bench
 
-tools:
-	go install github.com/fzipp/gocyclo/cmd/[email protected]
-	go install github.com/rinchsan/gosimports/cmd/[email protected]
+# ============================================================================
+# Testing targets
+# ============================================================================
 
+## bench: Run benchmark tests with memory profiling
 bench:
 	go test -bench=. -benchmem
 
+## test: Run tests with coverage (runs fmt, vet, and cyclo first)
+test: fmt vet cyclo
+	go test -cover -coverprofile=.coverprofile ./...
+
+## test-race: Run progress demo with race detector
+test-race:
+	go run -race ./cmd/demo-progress/demo.go
+
+# ============================================================================
+# Code quality targets
+# ============================================================================
+
+## cyclo: Check cyclomatic complexity (warns if complexity > 13)
 cyclo:
 	gocyclo -over 13 ./*/*.go
 
+## fmt: Format code and organize imports
+fmt:
+	go fmt ./...
+	gosimports -w .
+
+## vet: Run go vet static analysis
+vet:
+	go vet ./...
+
+# ============================================================================
+# Demo targets
+# ============================================================================
+
+## demo-colors: Run the colors demo
+demo-colors:
+	go run cmd/demo-colors/demo.go
+
+## demo-list: Run the list demo
 demo-list:
 	go run cmd/demo-list/demo.go
 
+## demo-progress: Run the progress demo
 demo-progress:
 	go run cmd/demo-progress/demo.go
 
+## demo-table: Run the table demo
 demo-table:
 	go run cmd/demo-table/demo.go
 
-fmt:
-	go fmt ./...
-	gosimports -w .
+# ============================================================================
+# Utility targets
+# ============================================================================
 
+## help: Display help information for all available targets
+help:
+	@echo "\033[1mAvailable targets:\033[0m"
+	@awk '/^# [A-Z].*targets$$/ {gsub(/^# /, ""); print "\n\033[1;36m" $$0 "\033[0m"} /^##/ {gsub(/^##\s*/, ""); idx=match($$0, /: /); if(idx) {target=substr($$0,1,idx-1); desc=substr($$0,idx+2); printf "  \033[36mmake\033[0m \033[32m%-15s\033[0m \033[33m- %s\033[0m\n", target, desc}}' $(MAKEFILE_LIST)
+
+## profile: Run profiling script
 profile:
 	sh profile.sh
 
-test: fmt vet cyclo
-	go test -cover -coverprofile=.coverprofile ./...
-
-test-race:
-	go run -race ./cmd/demo-progress/demo.go
-
-vet:
-	go vet ./...
+## tools: Install required development tools
+tools:
+	go install github.com/fzipp/gocyclo/cmd/[email protected]
+	go install github.com/rinchsan/gosimports/cmd/[email protected]
 

cmd/demo-colors/README.md

@@ -0,0 +1,13 @@
+# 256-Color Palette Demo
+
+This demo showcases the 256-color ANSI palette support in go-pretty.
+
+## Usage
+
+```bash
+go run ./cmd/demo-colors
+```
+
+## Screenshot
+
+![256-Color Palette Demo](demo.png)

cmd/demo-colors/demo.go

@@ -0,0 +1,117 @@
+package main
+
+import (
+	"fmt"
+
+	"github.com/jedib0t/go-pretty/v6/table"
+	"github.com/jedib0t/go-pretty/v6/text"
+)
+
+func main() {
+	tw := table.NewWriter()
+	tw.AppendRows([]table.Row{
+		{renderGrid(false)},
+		{renderGrid(true)},
+	})
+	tw.SetTitle("256-Color Palette")
+	tw.SetStyle(table.StyleLight)
+	tw.Style().Options.SeparateRows = true
+	tw.Style().Title.Align = text.AlignCenter
+	fmt.Println(tw.Render())
+}
+
+func alignCode(code int) string {
+	return " " + text.AlignRight.Apply(fmt.Sprint(code), 3) + " "
+}
+
+func blankTable() table.Writer {
+	tw := table.NewWriter()
+	tw.SetStyle(table.StyleLight)
+	style := tw.Style()
+	style.Box.PaddingLeft = ""
+	style.Box.PaddingRight = ""
+	style.Options.DrawBorder = false
+	style.Options.SeparateRows = false
+	style.Options.SeparateColumns = false
+	return tw
+}
+
+func buildRow(start, end int, isBackground bool) table.Row {
+	row := make(table.Row, 0, end-start)
+	for i := start; i < end; i++ {
+		row = append(row, cellValue(i, isBackground))
+	}
+	return row
+}
+
+func cellValue(code int, isBackground bool) string {
+	if isBackground {
+		return text.Colors{text.Bg256Color(code), text.FgBlack}.Sprint(alignCode(code))
+	}
+	return text.Colors{text.BgBlack, text.Fg256Color(code)}.Sprint(alignCode(code))
+}
+
+func renderGrid(isBackground bool) string {
+	tw := table.NewWriter()
+	tw.SetIndexColumn(1)
+	title := "Foreground Colors"
+	if isBackground {
+		title = "Background Colors"
+	}
+	tw.SetTitle(text.Underline.Sprint(title) + "\n")
+	tw.SetStyle(table.StyleLight)
+	style := tw.Style()
+	style.Box.PaddingLeft = ""
+	style.Box.PaddingRight = ""
+	style.Options.DrawBorder = false
+	style.Options.SeparateRows = false
+	style.Options.SeparateColumns = false
+	style.Title.Align = text.AlignCenter
+	tw.SetColumnConfigs([]table.ColumnConfig{
+		{Number: 1, Align: text.AlignCenter},
+	})
+
+	// Standard 16 colors (0-15)
+	row16 := blankTable()
+	row16.AppendRow(buildRow(0, 16, isBackground))
+	tw.AppendRows([]table.Row{{row16.Render()}, {""}})
+
+	// RGB cube colors (16-231) - 216 colors in 6 blocks of 36
+	row216 := blankTable()
+	blockRow := make(table.Row, 0)
+	for block := 0; block < 6; block++ {
+		blockStart := 16 + 36*block
+		blockTable := blankTable()
+		colors := buildRow(blockStart, blockStart+36, isBackground)
+		for i := 0; i < len(colors); i += 6 {
+			end := i + 6
+			if end > len(colors) {
+				end = len(colors)
+			}
+			blockTable.AppendRow(colors[i:end])
+		}
+		blockRow = append(blockRow, blockTable.Render())
+		if len(blockRow) == 3 {
+			row216.AppendRow(blockRow)
+			blockRow = make(table.Row, 0)
+		}
+	}
+	if len(blockRow) > 0 {
+		row216.AppendRow(blockRow)
+	}
+	tw.AppendRows([]table.Row{{row216.Render()}, {""}})
+
+	// Grayscale colors (232-255) - 24 colors
+	rowGrayscale := blankTable()
+	colors := buildRow(232, 256, isBackground)
+	for i := 0; i < len(colors); i += 12 {
+		end := i + 12
+		if end > len(colors) {
+			end = len(colors)
+		}
+		rowGrayscale.AppendRow(colors[i:end])
+	}
+	tw.AppendRows([]table.Row{{rowGrayscale.Render()}})
+
+	return tw.Render()
+}

cmd/demo-colors/demo.png

@@ -15,6 +15,11 @@ Used heavily in the other packages in this repo ([list](../list),
     - Foreground colors (Black, Red, Green, Yellow, Blue, Magenta, Cyan, White)
     - Background colors (matching foreground set)
     - Hi-intensity variants for both foreground and background
+    - **256-color palette support** - Extended color support for terminals
+      - Standard 16 colors (0-15)
+      - RGB cube colors (16-231) - 216 colors organized in a 6x6x6 cube
+      - Grayscale colors (232-255) - 24 shades of gray
+      - Helper functions: `Fg256Color(index)`, `Bg256Color(index)`, `Fg256RGB(r, g, b)`, `Bg256RGB(r, g, b)`
     - Text attributes (Bold, Faint, Italic, Underline, Blink, Reverse, Concealed, CrossedOut)
     - Automatic color detection based on environment variables (`NO_COLOR`, `FORCE_COLOR`, `TERM`)
     - Global enable/disable functions for colors
@@ -76,6 +81,7 @@ Used heavily in the other packages in this repo ([list](../list),
     - `EscSeqParser` - Parser for advanced escape sequence parsing and tracking
       - Supports both CSI (Control Sequence Introducer) and OSI (Operating System Command) formats
       - Tracks active formatting codes and can generate consolidated escape sequences
+      - Full support for 256-color escape sequences (`\x1b[38;5;n`m` and `\x1b[48;5;n`m`)
 
 ### Cursor Control
 

text/README.md

@@ -3,6 +3,12 @@
 
 package text
 
+import "os"
+
 func areANSICodesSupported() bool {
-	return true
+	// On Unix systems, ANSI codes are generally supported unless TERM is "dumb"
+	// This is a basic check; 256-color sequences are ANSI sequences and will
+	// be handled by terminals that support them (or ignored by those that don't)
+	term := os.Getenv("TERM")
+	return term != "dumb"
 }