Merge pull request #399 from KrisVandermotten/StringLineGroup

Some optimizations in StringLineGroup
xoofx · Feb 18, 2020 · ef5b958 · ef5b958
2 parents 51f9da1 + 7d61df2
commit ef5b958
Showing 1 changed file with 17 additions and 29 deletions.
diff --git a/src/Markdig/Helpers/StringLineGroup.cs b/src/Markdig/Helpers/StringLineGroup.cs
@@ -69,16 +69,13 @@ public void Clear()
         /// <param name="index">The index.</param>
         public void RemoveAt(int index)
         {
-            if (Count - 1 == index)
-            {
-                Count--;
-            }
-            else
+            if (index != Count - 1)
             {
                 Array.Copy(Lines, index + 1, Lines, index, Count - index - 1);
-                Lines[Count - 1] = new StringLine();
-                Count--;
             }
+
+            Lines[Count - 1] = new StringLine();
+            Count--;
         }
 
         /// <summary>
@@ -115,22 +112,19 @@ public readonly override string ToString()
         /// <returns>A single slice concatenating the lines of this instance</returns>
         public readonly StringSlice ToSlice(List<LineOffset> lineOffsets = null)
         {
-            // Optimization case when no lines
-            if (Count == 0)
-            {
-                return new StringSlice(string.Empty);
-            }
-
             // Optimization case for a single line.
             if (Count == 1)
             {
-                if (lineOffsets != null)
-                {
-                    lineOffsets.Add(new LineOffset(Lines[0].Position, Lines[0].Column, Lines[0].Slice.Start - Lines[0].Position, Lines[0].Slice.Start, Lines[0].Slice.End + 1));
-                }
+                lineOffsets?.Add(new LineOffset(Lines[0].Position, Lines[0].Column, Lines[0].Slice.Start - Lines[0].Position, Lines[0].Slice.Start, Lines[0].Slice.End + 1));
                 return Lines[0];
             }
 
+            // Optimization case when no lines
+            if (Count == 0)
+            {
+                return new StringSlice(string.Empty);
+            }
+
             if (lineOffsets != null && lineOffsets.Capacity < lineOffsets.Count + Count)
             {
                 lineOffsets.Capacity = Math.Max(lineOffsets.Count + Count, lineOffsets.Capacity * 2);
@@ -143,21 +137,16 @@ public readonly StringSlice ToSlice(List<LineOffset> lineOffsets = null)
             {
                 if (i > 0)
                 {
-                    if (lineOffsets != null)
-                    {
-                        lineOffsets.Add(new LineOffset(Lines[i - 1].Position, Lines[i - 1].Column, Lines[i - 1].Slice.Start - Lines[i - 1].Position, previousStartOfLine, builder.Length));
-                    }
                     builder.Append('\n');
                     previousStartOfLine = builder.Length;
                 }
-                if (!Lines[i].Slice.IsEmpty)
+                ref var line = ref Lines[i];
+                if (!line.Slice.IsEmpty)
                 {
-                    builder.Append(Lines[i].Slice.Text, Lines[i].Slice.Start, Lines[i].Slice.Length);
+                    builder.Append(line.Slice.Text, line.Slice.Start, line.Slice.Length);
                 }
-            }
-            if (lineOffsets != null)
-            {
-                lineOffsets.Add(new LineOffset(Lines[Count - 1].Position, Lines[Count - 1].Column, Lines[Count - 1].Slice.Start - Lines[Count - 1].Position, previousStartOfLine, builder.Length));
+
+                lineOffsets?.Add(new LineOffset(line.Position, line.Column, line.Slice.Start - line.Position, previousStartOfLine, builder.Length));
             }
             return new StringSlice(builder.GetStringAndReset());
         }
@@ -268,10 +257,10 @@ public StringLineGroup Remaining()
             public char NextChar()
             {
                 Start++;
-                _offset++;
                 if (Start <= End)
                 {
                     var slice = _lines.Lines[SliceIndex].Slice;
+                    _offset++;
                     if (_offset < slice.Length)
                     {
                         CurrentChar = slice[slice.Start + _offset];
@@ -288,7 +277,6 @@ public char NextChar()
                     CurrentChar = '\0';
                     Start = End + 1;
                     SliceIndex = _lines.Count;
-                    _offset--;
                 }
                 return CurrentChar;
             }