From aaa46b5372b748da982aa7f77635d0be772847ae Mon Sep 17 00:00:00 2001
From: Richard Hull <rm_hull@yahoo.co.uk>
Date: Sat, 8 Nov 2025 00:48:27 +0000
Subject: [PATCH 1/2] test: Test empty string input handling

Adds a test case to `TestStringWrap` to verify that an empty
string input correctly yields an empty string output.
---
 stringwrap_test.go | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/stringwrap_test.go b/stringwrap_test.go
index 0231184..44c03fa 100644
--- a/stringwrap_test.go
+++ b/stringwrap_test.go
@@ -129,6 +129,13 @@ func TestStringWrap(t *testing.T) {
 			trimWhitespace: true,
 			splitWord:      true,
 		},
+		{
+			input:          "",
+			wrapped:        "",
+			limit:          5,
+			trimWhitespace: true,
+			splitWord:      true,
+		},
 	}
 
 	for idx, tt := range tests {

From 4b4b23fbd981a53184c757b04b61313fedcb9292 Mon Sep 17 00:00:00 2001
From: Richard Hull <rm_hull@yahoo.co.uk>
Date: Sat, 8 Nov 2025 10:21:19 +0000
Subject: [PATCH 2/2] fix: sidestep panic accessing last wrapped line of empty
 sequence

The function `lastWrappedLine` is updated to safely return `nil`
if the internal sequence of wrapped lines is empty, avoiding
a runtime panic (index out of bounds).

The main wrapping logic now checks for a `nil` return before
accessing the line properties.

Testing logic for zero-length wrapped strings was also fixed
to correctly assert line counts for empty output.
---
 stringwrap.go      | 8 ++++++--
 stringwrap_test.go | 6 +++++-
 2 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/stringwrap.go b/stringwrap.go
index bedf92e..ab9c8d8 100644
--- a/stringwrap.go
+++ b/stringwrap.go
@@ -89,7 +89,11 @@ type WrappedStringSeq struct {
 
 // lastWrappedLine pulls the last wrapped line that has been parsed
 func (s *WrappedStringSeq) lastWrappedLine() *WrappedString {
-	return &s.WrappedLines[len(s.WrappedLines)-1]
+	n := len(s.WrappedLines)
+	if n == 0 {
+		return nil
+	}
+	return &s.WrappedLines[n-1]
 }
 
 // appendWrappedSeq adds a new WrappedString to the existing slice
@@ -489,7 +493,7 @@ func stringWrap(
 	// remove the last new line from the wrapped buffer
 	// if the last line is not a hard break.
 	lastWrappedLine := wrappedStringSeq.lastWrappedLine()
-	if !lastWrappedLine.IsHardBreak {
+	if lastWrappedLine != nil && !lastWrappedLine.IsHardBreak {
 		stateMachine.buffer.Truncate(stateMachine.buffer.Len() - 1)
 		lastWrappedLine.LastSegmentInOrig = true
 	}
diff --git a/stringwrap_test.go b/stringwrap_test.go
index 44c03fa..e400575 100644
--- a/stringwrap_test.go
+++ b/stringwrap_test.go
@@ -141,8 +141,12 @@ func TestStringWrap(t *testing.T) {
 	for idx, tt := range tests {
 		t.Run(fmt.Sprintf("Wrapped String Test %d", idx+1), func(t *testing.T) {
 			wrapped, seq, err := wrapString(tt)
+			expectedLines := 0
+			if wrapped != "" {
+				expectedLines = len(strings.Split(wrapped, "\n"))
+			}
 			assert.Nil(t, err)
-			assert.Equal(t, len(seq.WrappedLines), len(strings.Split(wrapped, "\n")))
+			assert.Equal(t, expectedLines, len(seq.WrappedLines))
 			assert.Equal(t, tt.wrapped, wrapped)
 		})
 	}