Don't crash when tables have empty rows

Author: ian-craig

src/ReverseMarkdown.Test/ConverterTests.cs

@@ -889,6 +889,24 @@ public void WhenTable_CellContainsBr_PreserveBrAndConvertToGFMTable()
             });
         }
 
+        [Fact]
+        public void WhenTable_HasEmptyRow_DropsEmptyRow()
+        {
+            const string html =
+                @"<table><tr><td>abc</td></tr><tr></tr></table>";
+            var expected = $"{Environment.NewLine}{Environment.NewLine}";
+            expected += $"| <!----> |{Environment.NewLine}";
+            expected += $"| --- |{Environment.NewLine}";
+            expected += $"| abc |{Environment.NewLine}";
+            expected += Environment.NewLine;
+
+            CheckConversion(html, expected, new Config
+            {
+                GithubFlavored = true,
+                TableWithoutHeaderRowHandling = Config.TableWithoutHeaderRowHandlingOption.EmptyRow,
+            });
+        }
+
         [Fact]
         public void When_BR_With_GitHubFlavored_Config_ThenConvertToGFM_BR()
         {

src/ReverseMarkdown/Converters/Table.cs

@@ -51,8 +51,8 @@ private static string EmptyHeader(HtmlNode node)
                 underlineRowItems.Add("---");
             }
 
-            var headerRow = $"| {headerRowItems.Aggregate((item1, item2) => item1 + " | " + item2)} |{Environment.NewLine}";
-            var underlineRow = $"| {underlineRowItems.Aggregate((item1, item2) => item1 + " | " + item2)} |{Environment.NewLine}";
+            var headerRow = $"| {string.Join(" | ", headerRowItems)} |{Environment.NewLine}";
+            var underlineRow = $"| {string.Join(" | ", underlineRowItems)} |{Environment.NewLine}";
 
             return headerRow + underlineRow;
         }

src/ReverseMarkdown/Converters/Tr.cs

@@ -17,6 +17,11 @@ public override string Convert(HtmlNode node)
         {
             var content = TreatChildren(node).TrimEnd();
             var underline = "";
+
+            if (string.IsNullOrWhiteSpace(content))
+            {
+                return "";
+            }
 
             if (IsTableHeaderRow(node) || UseFirstRowAsHeaderRow(node))
             {
@@ -61,7 +66,7 @@ private string UnderlineFor(HtmlNode node)
                 cols.Add("---");
             }
 
-            var colsAggregated = cols.Aggregate((item1, item2) => item1 + " | " + item2);
+            var colsAggregated = string.Join(" | ", cols);
 
             return $"| {colsAggregated} |{Environment.NewLine}";
         }