From 738bd5f6712b1c76cb3ac8d0d9a6ba3951ad7b78 Mon Sep 17 00:00:00 2001
From: mysticmnd <babu.annamalai@gmail.com>
Date: Sat, 29 Jun 2024 06:12:31 +0530
Subject: [PATCH] Fix GH-393 regression with mixed new line characters

---
 ...Tests.Bug393_RegressionWithVaryingNewLines.verified.md | 7 +++++++
 src/ReverseMarkdown.Test/ConverterTests.cs                | 8 ++++++++
 src/ReverseMarkdown.Test/ReverseMarkdown.Test.csproj      | 3 +++
 src/ReverseMarkdown/StringUtils.cs                        | 4 ++--
 4 files changed, 20 insertions(+), 2 deletions(-)
 create mode 100644 src/ReverseMarkdown.Test/ConverterTests.Bug393_RegressionWithVaryingNewLines.verified.md

diff --git a/src/ReverseMarkdown.Test/ConverterTests.Bug393_RegressionWithVaryingNewLines.verified.md b/src/ReverseMarkdown.Test/ConverterTests.Bug393_RegressionWithVaryingNewLines.verified.md
new file mode 100644
index 0000000..fa57f5f
--- /dev/null
+++ b/src/ReverseMarkdown.Test/ConverterTests.Bug393_RegressionWithVaryingNewLines.verified.md
@@ -0,0 +1,7 @@
+This is regular text
+
+This is HTML: 
+
+* Line 1
+* Line 2
+* Line 3 has an unknown tag
\ No newline at end of file
diff --git a/src/ReverseMarkdown.Test/ConverterTests.cs b/src/ReverseMarkdown.Test/ConverterTests.cs
index ba5c600..1099cff 100644
--- a/src/ReverseMarkdown.Test/ConverterTests.cs
+++ b/src/ReverseMarkdown.Test/ConverterTests.cs
@@ -1376,5 +1376,13 @@ public Task Bug391_AnchorTagUnnecessarilyIndented()
             
             return CheckConversion(html, config);
         }
+
+        [Fact]
+        public Task Bug393_RegressionWithVaryingNewLines()
+        {
+            const string html = "This is regular text\r\n<p class=\"c1\">This is HTML: <ul><li>Line 1</li><li>Line 2</li><li><mark>Line 3 has an unknown tag</mark></li></ul></p>";
+            var config = new Config { UnknownTags = Config.UnknownTagsOption.Bypass, ListBulletChar = '*' };
+            return CheckConversion(html, config);
+        }
     }
 }
diff --git a/src/ReverseMarkdown.Test/ReverseMarkdown.Test.csproj b/src/ReverseMarkdown.Test/ReverseMarkdown.Test.csproj
index 74df7f3..7270403 100644
--- a/src/ReverseMarkdown.Test/ReverseMarkdown.Test.csproj
+++ b/src/ReverseMarkdown.Test/ReverseMarkdown.Test.csproj
@@ -50,6 +50,9 @@
     </None>
     <None Update="ConverterTests.Bug391_AnchorTagUnnecessarilyIndented.verified.md">
       <DependentUpon>ConverterTests.WhenThereIsSingleAsteriskInText_ThenConvertToMarkdownEscapedAsterisk.verified.md</DependentUpon>
+    </None>
+    <None Update="ConverterTests.Bug393_RegressionWithVaryingNewLines.verified.md">
+      <DependentUpon>ConverterTests.WhenThereIsPreTag_ThenConvertToMarkdownPre.verified.md</DependentUpon>
     </None> 
   </ItemGroup>
 </Project>
diff --git a/src/ReverseMarkdown/StringUtils.cs b/src/ReverseMarkdown/StringUtils.cs
index cc54a24..9f434b1 100644
--- a/src/ReverseMarkdown/StringUtils.cs
+++ b/src/ReverseMarkdown/StringUtils.cs
@@ -123,8 +123,8 @@ public static string EmphasizeContentWhitespaceGuard(this string content, string
         
         public static string FixMultipleNewlines(this string markdown)
         {
-            var normalizedMarkdown = Regex.Replace(markdown, @"\r\n|\r|\n", "\n");
-            var pattern = @"\n{2,}";
+            var normalizedMarkdown = Regex.Replace(markdown, @"\r\n|\r|\n", Environment.NewLine);
+            var pattern = $"{Environment.NewLine}{{2,}}";
             return Regex.Replace(normalizedMarkdown, pattern, Environment.NewLine + Environment.NewLine);
         }