Working on keeping the closing tag of an element clean. (#1789)

closes #1785

Author: belav

Src/CSharpier.Core/Xml/RawNode.cs

@@ -31,4 +31,29 @@ public RawNode GetLastDescendant()
     {
         return this.NodeType is XmlNodeType.Element ? this.Nodes.LastOrDefault() ?? this : this;
     }
+
+    public override string? ToString()
+    {
+        if (this.IsTextLike())
+        {
+            return this.Value;
+        }
+
+        if (this.NodeType is XmlNodeType.Element)
+        {
+            if (this.IsEmpty)
+            {
+                return "<" + this.Name + " />";
+            }
+
+            return "<" + this.Name;
+        }
+
+        if (this.NodeType is XmlNodeType.EndElement)
+        {
+            return "</" + this.Name + ">";
+        }
+
+        return base.ToString();
+    }
 }

Src/CSharpier.Core/Xml/XNodePrinters/Element.cs

@@ -66,6 +66,15 @@ Doc PrintLineAfterChildren()
             {
                 return Doc.Null;
             }
+
+            if (
+                rawNode.Nodes is [{ NodeType: XmlNodeType.Text }]
+                && rawNode.Nodes[0].Value.TrimEnd(' ')[^1] is 'r' or '\n'
+            )
+            {
+                return Doc.Null;
+            }
+
             return Doc.SoftLine;
         }
 

Src/CSharpier.Core/Xml/XNodePrinters/Tag.cs

@@ -53,7 +53,7 @@ public static Doc PrintClosingTagStart(RawNode rawNode, PrintingContext context)
     {
         var lastChild = rawNode.Nodes.LastOrDefault();
 
-        return lastChild is not null && NeedsToBorrowParentClosingTagStartMarker(lastChild)
+        return lastChild is not null && PrintParentClosingTagStartWithContent(lastChild)
             ? Doc.Null
             : PrintClosingTagStartMarker(rawNode, context);
     }
@@ -78,7 +78,7 @@ public static Doc PrintClosingTagEndMarker(RawNode rawNode)
 
     public static Doc PrintClosingTagSuffix(RawNode rawNode, PrintingContext context)
     {
-        return NeedsToBorrowParentClosingTagStartMarker(rawNode)
+        return PrintParentClosingTagStartWithContent(rawNode)
                 ? PrintClosingTagStartMarker(rawNode.Parent!, context)
             : NeedsToBorrowNextOpeningTagStartMarker(rawNode)
                 ? PrintOpeningTagStartMarker(rawNode.NextNode!, context)
@@ -113,7 +113,7 @@ private static bool NeedsToBorrowNextOpeningTagStartMarker(RawNode rawNode)
         ;
     }
 
-    private static bool NeedsToBorrowParentClosingTagStartMarker(RawNode rawNode)
+    private static bool PrintParentClosingTagStartWithContent(RawNode rawNode)
     {
         /*
          *     <p>
@@ -126,9 +126,35 @@ private static bool NeedsToBorrowParentClosingTagStartMarker(RawNode rawNode)
          *        ^^^
          *     >
          */
+        // TODO #1790 we really want this last condition only if the indentation of the last line of the text value matches
+        // the indentation of the start element. Bleh.
+        /*
+may have to handle one of these vs the second
+<Root>
+  <Element Attribute="TheSign">
+    Life is demanding.
+    </Element>
+</Root>
+<Root>
+  <Element Attribute="TheSign">
+    Life is demanding.
+  </Element>
+</Root>
+there is also this case
+<Root>
+       <Element >
+    Life is demanding.
+         </Element>
+</Root>
+         */
         return rawNode.NextNode is null
             && rawNode.IsTextLike()
-            && rawNode.GetLastDescendant().NodeType is XmlNodeType.Text;
+            && rawNode.GetLastDescendant() is { NodeType: XmlNodeType.Text } textNode
+            && (
+                textNode.Value[^1] is not (' ' or '\r' or '\n')
+                || !textNode.Value.Contains('\n')
+                || rawNode.Parent!.Nodes.Any(o => !o.IsTextLike())
+            );
     }
 
     public static bool NeedsToBorrowParentOpeningTagEndMarker(RawNode rawNode)

Src/CSharpier.Tests/FormattingTests/TestFiles/xml/Attributes.test

@@ -11,4 +11,7 @@
             AND '$(MSBuildProjectName)' != 'System.Net.Http.Formatting.NetCore.Test'
             AND '$(MSBuildProjectName)' != 'System.Net.Http.Formatting.NetStandard.Test' "
   />
+  <Element Attribute="TheSign">
+    Life is demanding.
+  </Element>
 </Root>

Src/CSharpier.Tests/FormattingTests/TestFiles/xml/StrictWhitespace.test

@@ -3,9 +3,34 @@
 
     Because whitespace is strict
     The indentation of the closing element can't change
-      </Element
-  >
+      </Element>
   <Element>
     Shorter Text with indentation that can't change
     </Element>
+  <returns>
+    <para
+      >A <see cref="T:System.Int32" /> containing a value that reflects the sort order of
+  <paramref name="x" /> as compared to <paramref name="y" />. The following table defines the conditions
+  under which the returned value is a negative number, zero, or a positive
+  number.</para
+    >
+  </returns>
+  <para>Some text that ends with a space. </para>
+  <para
+    >Some loooooooooooooooooooooooooooooooooong text with this <br /> and a space after this. </para
+  >
+  <exception cref="T:System.InvalidOperationException"
+    >The current instance is read-only and a set operation was attempted. </exception
+  >
+  <example>
+    <code>public void MethodName() {
+}
+        </code>
+  </example>
+  <Root>
+    <Element />
+    <!--
+    SomeText
+    -->
+  </Root>
 </Root>