Fix WordWrap bounds out of range

Resolves #27.

CHANGELOG

@@ -4,6 +4,7 @@ v1.5.1 (WIP)
 - Add TextView.SetBytes and TextView.GetBytes
 - Add TableCell.SetBytes, TableCell.GetBytes and TableCell.GetText
 - Fix List.Transform not calling handler set via SetChangedFunc
+- Fix WordWrap bounds out of range
 - Allow modification of scroll bar render text
 - Optimize TextView (writing is 90% faster, drawing is 50% faster)
 - Remove return values from methods which return their primitive (breaks chaining)

README.md

@@ -41,7 +41,7 @@ go get gitlab.com/tslocum/cview
 
 ## Hello World
 
-This basic example creates a box titled "Hello, World!" and displays it in your terminal:
+This basic example creates a TextView titled "Hello, World!" and displays it in your terminal:
 
 ```go
 package main

go.mod

@@ -8,5 +8,5 @@ require (
 	github.com/mattn/go-runewidth v0.0.9
 	github.com/rivo/uniseg v0.1.0
 	gitlab.com/tslocum/cbind v0.1.2
-	golang.org/x/sys v0.0.0-20200930185726-fdedc70b468f // indirect
+	golang.org/x/sys v0.0.0-20201009025420-dfb3f7c4e634 // indirect
 )

go.sum

@@ -15,8 +15,8 @@ gitlab.com/tslocum/cbind v0.1.2/go.mod h1:HfB7qAhHSZbn1rFK8M9SvSN5NG6ScAg/3h3iE6
 golang.org/x/sys v0.0.0-20190626150813-e07cf5db2756/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200826173525-f9321e4c35a6 h1:DvY3Zkh7KabQE/kfzMvYvKirSiguP9Q/veMtkYyf0o8=
 golang.org/x/sys v0.0.0-20200826173525-f9321e4c35a6/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20200930185726-fdedc70b468f h1:+Nyd8tzPX9R7BWHguqsrbFdRx3WQ/1ib8I44HXV5yTA=
-golang.org/x/sys v0.0.0-20200930185726-fdedc70b468f/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20201009025420-dfb3f7c4e634 h1:bNEHhJCnrwMKNMmOx3yAynp5vs5/gRy+XWFtZFu7NBM=
+golang.org/x/sys v0.0.0-20201009025420-dfb3f7c4e634/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.3 h1:cokOdA+Jmi5PJGXLlLllQSgYigAEfHXJAERHVMaCc2k=
 golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=

slider.go

@@ -153,10 +153,7 @@ func (s *Slider) GetFieldHeight() int {
 
 // GetFieldWidth returns this primitive's field width.
 func (s *Slider) GetFieldWidth() int {
-	s.RLock()
-	defer s.RUnlock()
-
-	return 7
+	return 0
 }
 
 // SetIncrement sets the amount the slider is incremented by when modified via

util.go

@@ -7,7 +7,7 @@ import (
 	"strconv"
 
 	"github.com/gdamore/tcell/v2"
-	runewidth "github.com/mattn/go-runewidth"
+	"github.com/mattn/go-runewidth"
 	"github.com/rivo/uniseg"
 )
 
@@ -490,6 +490,9 @@ func WordWrap(text string, width int) (lines []string) {
 		for index := escapePos; index >= 0; index-- {
 			if index < len(escapeIndices) && startIndex > escapeIndices[index][0] && startIndex < escapeIndices[index][1]-1 {
 				pos := escapeIndices[index][1] - 2 - startIndex
+				if pos < 0 || pos > len(substr) {
+					return substr
+				}
 				return substr[:pos] + substr[pos+1:]
 			}
 		}