Fix ten bugs from a random sweep of libse/libuilogic

src/libse/Common/ActorConverter.cs

@@ -73,10 +73,12 @@ public string FixActorsFromActor(Paragraph p, int? changeCasing, SKColor? color)
         public string FixActorsFromBeforeColon(Paragraph p, char ch, int? changeCasing, SKColor? color)
         {
             var sb = new StringBuilder();
+            var lineIdx = 0;
             foreach (var line in p.Text.SplitToLines())
             {
+                // index into the trimmed line - leading whitespace used to shift every cut by its width
                 var s = line.Trim();
-                var startIdx = line.IndexOf(ch);
+                var startIdx = s.IndexOf(ch);
                 if (startIdx > 0)
                 {
                     var actor = s.Substring(0, startIdx).Trim(' ', '-', '"');
@@ -97,34 +99,29 @@ public string FixActorsFromBeforeColon(Paragraph p, char ch, int? changeCasing,
                     {
                         actor = actor + ":";
                     }
-                    else if (ToActor)
-                    {
-                    }
 
                     if (color.HasValue && !ToActor)
                     {
-                        SetColor(_subtitleFormat, color.Value, actor);
+                        actor = SetColor(_subtitleFormat, color.Value, actor);
                     }
 
-                    if (ToSquare)
-                    {
-                        s = actor + " " + s.Substring(startIdx + 1).TrimStart(' ');
-                    }
-                    else if (ToParentheses)
+                    if (ToActor)
                     {
-                        s = actor + " " + s.Substring(startIdx + 1).TrimStart(' ');
+                        if (lineIdx == 0)
+                        {
+                            p.Actor = actor;
+                        }
+
+                        s = s.Substring(startIdx + 1).TrimStart(' ');
                     }
-                    else if (ToColon)
+                    else
                     {
                         s = actor + " " + s.Substring(startIdx + 1).TrimStart(' ');
                     }
-                    else if (ToActor)
-                    {
-                        s = s.Substring(startIdx + 1);
-                    }
                 }
 
                 sb.AppendLine(s);
+                lineIdx++;
             }
 
             return sb.ToString().Trim();
@@ -269,6 +266,8 @@ private static string SetColor(SubtitleFormat format, SKColor color, string acto
             return actor;
         }
 
+        private static readonly string[] CommonTitles = { "Mr.", "Mrs.", "Dr." };
+
         private bool IsActor(string s)
         {
             if (string.IsNullOrWhiteSpace(s))
@@ -294,15 +293,14 @@ private bool IsActor(string s)
                     return false;
                 }
 
-                if (word.Any(c => char.IsDigit(c) || (!char.IsLetter(c) && c != '-' && c != '\'')))
+                if (CommonTitles.Contains(word))
                 {
-                    return false;
+                    continue;
                 }
 
-                var commonTitles = new[] { "Mr.", "Mrs.", "Dr.", };
-                if (commonTitles.Contains(word))
+                if (word.Any(c => char.IsDigit(c) || (!char.IsLetter(c) && c != '-' && c != '\'')))
                 {
-                    continue;
+                    return false;
                 }
 
                 if (!_nameListInclMulti.Contains(word, StringComparer.OrdinalIgnoreCase))

src/libse/Common/FixCasing.cs

@@ -95,7 +95,7 @@ private static string FixEnglishAloneILowerToUpper(string input)
 
             if (text.StartsWith("I-if ", StringComparison.Ordinal))
             {
-                text = text.Remove(0, 4).Insert(0, "I-If ");
+                text = text.Remove(0, 4).Insert(0, "I-If");
             }
 
             for (var indexOfI = text.IndexOf('i'); indexOfI >= 0; indexOfI = text.IndexOf('i', indexOfI + 1))
@@ -220,7 +220,7 @@ public static string FixStutter(string text)
                 }
                 else if (!tagOn && char.IsLetter(ch))
                 {
-                    if (firstLetter && index < text.Length - 6 && char.IsUpper(text[index]) &&
+                    if (firstLetter && index < text.Length - 5 && char.IsUpper(text[index]) &&
                         text[index + 1] == '-' && char.IsLower(text[index + 2]) && text[index] == char.ToUpperInvariant(text[index + 2]) &&
                         text[index + 3] == '-' && char.IsLower(text[index + 4]) && text[index] == char.ToUpperInvariant(text[index + 4]) &&
                         text[index + 5] != '-')
@@ -231,7 +231,7 @@ public static string FixStutter(string text)
                         sb.Append('-');
                         index += 4;
                     }
-                    else if (firstLetter && index < text.Length - 4 && char.IsUpper(text[index]) &&
+                    else if (firstLetter && index < text.Length - 3 && char.IsUpper(text[index]) &&
                              text[index + 1] == '-' && char.IsLower(text[index + 2]) && text[index] == char.ToUpperInvariant(text[index + 2]) &&
                              text[index + 3] != '-')
                     {

src/libse/Common/TextEffect/KaraokeWordTransform.cs

@@ -26,8 +26,9 @@ public override string[] Transform(string text)
                     var karaoke = text.Substring(0, i) + fontClose + text.Substring(i);
                     lastFontCloseIdx = i;
                     result.Add(karaoke);
-                    // skip only whitespace
-                    while (i < len && char.IsWhiteSpace(text[i]))
+                    // skip only whitespace - land on the last whitespace char so the loop's own
+                    // i++ moves onto the next word (or tag) instead of past it
+                    while (i + 1 < len && char.IsWhiteSpace(text[i + 1]))
                     {
                         i++;
                     }

src/libse/Common/Utilities.cs

@@ -3424,8 +3424,11 @@ public static Subtitle LoadMatroskaSSA(MatroskaTrackInfo matroskaSubtitleInfo, s
                 {
                     text = text.Remove(0, idx); // remove ReadOrder
                     idx = text.IndexOf(',');
-                    text = text.Insert(idx, "," + start + "," + end);
-                    lines.Add("Dialogue: " + text);
+                    if (idx >= 0)
+                    {
+                        text = text.Insert(idx, "," + start + "," + end);
+                        lines.Add("Dialogue: " + text);
+                    }
                 }
             }
             for (int commentIndex = 0; commentIndex < comments.Paragraphs.Count; commentIndex++)

src/libse/SubtitleFormats/UnknownSubtitle33.cs

@@ -65,8 +65,9 @@ public override string ToText(Subtitle subtitle, string title)
 
         private static string EncodeTimeCode(TimeCode timeCode)
         {
-            int seconds = (int)Math.Round(timeCode.Seconds + timeCode.Milliseconds / 1000.0);
-            return $"{timeCode.Hours:00}:{timeCode.Minutes:00}:{seconds:00}";
+            // round to whole seconds on the total so 59.6s carries into the minute instead of writing ":60"
+            var rounded = new TimeCode(Math.Round(timeCode.TotalMilliseconds / 1000.0) * 1000.0);
+            return $"{rounded.Hours:00}:{rounded.Minutes:00}:{rounded.Seconds:00}";
         }
 
         public override void LoadSubtitle(Subtitle subtitle, List<string> lines, string fileName)

src/libse/SubtitleFormats/UnknownSubtitle34.cs

@@ -41,8 +41,9 @@ public override string ToText(Subtitle subtitle, string title)
 
         private static string EncodeTimeCode(TimeCode timeCode)
         {
-            int seconds = (int)Math.Round(timeCode.Seconds + timeCode.Milliseconds / 1000.0);
-            return $"{timeCode.Hours:00}:{timeCode.Minutes:00}:{seconds:00}";
+            // round to whole seconds on the total so 59.6s carries into the minute instead of writing ":60"
+            var rounded = new TimeCode(Math.Round(timeCode.TotalMilliseconds / 1000.0) * 1000.0);
+            return $"{rounded.Hours:00}:{rounded.Minutes:00}:{rounded.Seconds:00}";
         }
 
         public override void LoadSubtitle(Subtitle subtitle, List<string> lines, string fileName)

src/libse/SubtitleFormats/UnknownSubtitle59.cs

@@ -41,8 +41,9 @@ public override string ToText(Subtitle subtitle, string title)
 
         private static string EncodeTimeCode(TimeCode timeCode)
         {
-            int seconds = (int)Math.Round(timeCode.Seconds + timeCode.Milliseconds / 1000.0);
-            return $"{timeCode.Hours:00}:{timeCode.Minutes:00}:{seconds:00}";
+            // round to whole seconds on the total so 59.6s carries into the minute instead of writing ":60"
+            var rounded = new TimeCode(Math.Round(timeCode.TotalMilliseconds / 1000.0) * 1000.0);
+            return $"{rounded.Hours:00}:{rounded.Minutes:00}:{rounded.Seconds:00}";
         }
 
         public override void LoadSubtitle(Subtitle subtitle, List<string> lines, string fileName)

src/libuilogic/Ocr/FixEngine/OcrFixReplaceList2.cs

@@ -759,7 +759,7 @@ public IEnumerable<string> CreateGuessesFromLetters(string word, string threeLet
 
                 foreach (var previousGuess in previousGuesses)
                 {
-                    for (var i = 0; i < previousGuess.Length - letter.Length; i++)
+                    for (var i = 0; i <= previousGuess.Length - letter.Length; i++)
                     {
                         if (previousGuess.AsSpan(i).StartsWith(letter, StringComparison.Ordinal))
                         {

src/ui/Features/Tools/ConvertActors/ConvertActorsViewModel.cs

@@ -154,6 +154,10 @@ private void UpdatePreview()
                 {
                     var updatedVm = new SubtitleLineViewModel(vm);
                     updatedVm.Text = newText;
+                    if (converter.ToActor)
+                    {
+                        updatedVm.Actor = p.Actor;
+                    }
                     items.Add(new ConvertActorsDisplayItem(vm) { NewText = newText, IsChecked = true, UpdatedViewModel = updatedVm });
                     count++;
                 }

tests/libse/Core/BugHunt20260823Test.cs

@@ -0,0 +1,102 @@
+using Nikse.SubtitleEdit.Core.Common;
+using Nikse.SubtitleEdit.Core.Common.TextEffect;
+using Nikse.SubtitleEdit.Core.SubtitleFormats;
+using SkiaSharp;
+
+namespace LibSETests.Core;
+
+public class BugHunt20260823Test
+{
+    [Fact]
+    public void ActorConverter_ColonSource_AppliesColor()
+    {
+        var c = new ActorConverter(new SubRip(), "en") { ToSquare = true };
+        var p = new Paragraph { Text = "Joe: How are you?" };
+        var result = c.FixActorsFromBeforeColon(p, ':', null, SKColors.Red);
+        Assert.StartsWith("<font color=\"#ff0000", result);
+        Assert.EndsWith("\">[Joe]</font> How are you?", result);
+    }
+
+    [Fact]
+    public void ActorConverter_ColonSource_LeadingWhitespace()
+    {
+        var c = new ActorConverter(new SubRip(), "en") { ToSquare = true };
+        var p = new Paragraph { Text = "   Joe: How are you?" };
+        var result = c.FixActorsFromBeforeColon(p, ':', null, null);
+        Assert.Equal("[Joe] How are you?", result);
+    }
+
+    [Fact]
+    public void ActorConverter_ColonSource_ToActor_SetsActor()
+    {
+        var c = new ActorConverter(new SubRip(), "en") { ToActor = true };
+        var p = new Paragraph { Text = "Joe: How are you?" };
+        var result = c.FixActorsFromBeforeColon(p, ':', null, null);
+        Assert.Equal("How are you?", result);
+        Assert.Equal("Joe", p.Actor);
+    }
+
+    [Fact]
+    public void ActorConverter_TitleIsAllowedInActorName()
+    {
+        var dataDir = Path.Combine(Path.GetTempPath(), "SeBugHunt20260823_" + Guid.NewGuid().ToString("N"));
+        Directory.CreateDirectory(Path.Combine(dataDir, "Dictionaries"));
+        File.WriteAllText(Path.Combine(dataDir, "Dictionaries", "names.xml"), "<names><name>John</name><blacklist></blacklist></names>");
+        var oldDataDir = Configuration.DataDirectory;
+        Configuration.DataDirectory = dataDir;
+        try
+        {
+            var c = new ActorConverter(new SubRip(), "en") { ToSquare = true };
+            Assert.True(c.FixActors(new Paragraph { Text = "[John] How are you?" }, '[', ']', null, null).Selected);
+            Assert.True(c.FixActors(new Paragraph { Text = "[Mr. John] How are you?" }, '[', ']', null, null).Selected);
+            Assert.False(c.FixActors(new Paragraph { Text = "[Mr. 3] How are you?" }, '[', ']', null, null).Selected);
+        }
+        finally
+        {
+            Configuration.DataDirectory = oldDataDir;
+            Directory.Delete(dataDir, true);
+        }
+    }
+
+    [Fact]
+    public void FixCasing_IIf_NoDoubleSpace()
+    {
+        var fc = new FixCasing("en") { FixNormal = true, Format = new SubRip() };
+        var s = new Subtitle(new List<Paragraph> { new Paragraph("I-if you say so.", 0, 2000) });
+        fc.Fix(s);
+        Assert.Equal("I-If you say so.", s.Paragraphs[0].Text);
+    }
+
+    [Fact]
+    public void FixStutter_AtEndOfText()
+    {
+        Assert.Equal("N-N-No", FixCasing.FixStutter("N-n-no"));
+        Assert.Equal("N-No", FixCasing.FixStutter("N-no"));
+    }
+
+    [Fact]
+    public void UnknownSubtitle33_SecondsRoundingCarries()
+    {
+        var sub = new Subtitle();
+        sub.Paragraphs.Add(new Paragraph("Hello", new TimeCode(0, 0, 59, 600).TotalMilliseconds, new TimeCode(0, 1, 2, 0).TotalMilliseconds));
+        Assert.StartsWith("00:01:00", new UnknownSubtitle33().ToText(sub, "t"));
+        Assert.StartsWith("00:01:00", new UnknownSubtitle34().ToText(sub, "t"));
+        Assert.StartsWith("00:01:00", new UnknownSubtitle59().ToText(sub, "t"));
+    }
+
+    [Fact]
+    public void KaraokeWordTransform_TagAfterSpaceIsKeptIntact()
+    {
+        var res = new KaraokeWordTransform().Transform("<font color=\"#ffffff\">Hello <font face=\"Arial\">world</font>");
+        Assert.Equal(2, res.Length);
+        Assert.Equal("<font color=\"#ffffff\">Hello</font> <font face=\"Arial\">world</font>", res[0]);
+        Assert.Equal("<font color=\"#ffffff\">Hello <font face=\"Arial\">world</font></font>", res[1]);
+    }
+
+    [Fact]
+    public void KaraokeWordTransform_MultipleSpaces()
+    {
+        var res = new KaraokeWordTransform().Transform("a  b c");
+        Assert.Equal(new[] { "a</font>  b c", "a  b</font> c", "a  b c</font>" }, res);
+    }
+}