Using slice of runes for calculating lengths

cui/cui.go

@@ -7,7 +7,6 @@ import (
 	"os"
 	"os/exec"
 	"strings"
-	"unicode/utf8"
 )
 
 var shapes = map[string]string{
@@ -82,10 +81,14 @@ func Clear(dir string) {
 
 }
 
-// takes the document content (as a slice) and modifies any lines that are longer
+// Takes the document content (as a slice of strings) and wraps any lines that
-// than the specified console width, splitting them over two lines. returns the
+// are longer than the specified console width. returns the amended document
-// amended document content as a slice.
+// content as a slice of strings.
-// word wrapping uses a "greedy" algorithm
+// Word wrapping uses a "greedy" algorithm, where long lines are split in to
+// words, and then rebuilt word by word to fill the available space. any
+// leftover words overflow to the next line.
+// To offer some support for unicode, some lengths are calculated using a slice
+// of runes in the following way: len([]rune(string))
 func wrapLines(s []string, consolewidth int) []string {
 	out := []string{}
 	for _, ln := range s {
@@ -172,65 +175,3 @@ func HandleAlternateScreen(opt string) {
 	// to run
 	_ = cmd.Run()
 }
-
-func wrapLines2(s []string, consolewidth int) []string {
-	out := []string{}
-	for _, ln := range s {
-		if utf8.RuneCountInString(ln) <= consolewidth {
-			out = append(out, ln)
-		} else {
-			words := strings.SplitAfter(ln, " ")
-			var subout bytes.Buffer
-			for i, wd := range words {
-				sublen := subout.Len()
-				wdlen := utf8.RuneCountInString(wd)
-				if sublen+wdlen <= consolewidth {
-					subout.WriteString(wd)
-					if i == len(words)-1 {
-						out = append(out, subout.String())
-					}
-				} else {
-					out = append(out, subout.String())
-					subout.Reset()
-					subout.WriteString(wd)
-					if i == len(words)-1 {
-						out = append(out, subout.String())
-						subout.Reset()
-					}
-				}
-			}
-		}
-	}
-	return out
-}
-
-func wrapLines3(s []string, consolewidth int) []string {
-	out := []string{}
-	for _, ln := range s {
-		if len(ln) <= consolewidth {
-			out = append(out, ln)
-		} else {
-			words := strings.SplitAfter(ln, " ")
-			var subout bytes.Buffer
-			for i, wd := range words {
-				sublen := subout.Len()
-				wdlen := len(wd)
-				if sublen+wdlen <= consolewidth {
-					subout.WriteString(wd)
-					if i == len(words)-1 {
-						out = append(out, subout.String())
-					}
-				} else {
-					out = append(out, subout.String())
-					subout.Reset()
-					subout.WriteString(wd)
-					if i == len(words)-1 {
-						out = append(out, subout.String())
-						subout.Reset()
-					}
-				}
-			}
-		}
-	}
-	return out
-}

cui/cui_test.go

@@ -69,6 +69,7 @@ func Test_wrapLines_incorrect_wrapping_endash(t *testing.T) {
 		}
 	}
 }
+
 func Benchmark_wrapLines(b *testing.B) {
 	teststring := []string{
 		"0123456789",
@@ -81,27 +82,3 @@ func Benchmark_wrapLines(b *testing.B) {
 		wrapLines(teststring, 20)
 	}
 }
-func Benchmark_wrapLines2(b *testing.B) {
-	teststring := []string{
-		"0123456789",
-		"a really long line that will prolly be wrapped",
-		"a l i n e w i t h a l o t o f w o r d s",
-		"onehugelongwordaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",
-	}
-	b.ResetTimer()
-	for n := 0; n < b.N; n++ {
-		wrapLines2(teststring, 20)
-	}
-}
-func Benchmark_wrapLines3(b *testing.B) {
-	teststring := []string{
-		"0123456789",
-		"a really long line that will prolly be wrapped",
-		"a l i n e w i t h a l o t o f w o r d s",
-		"onehugelongwordaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",
-	}
-	b.ResetTimer()
-	for n := 0; n < b.N; n++ {
-		wrapLines3(teststring, 20)
-	}
-}