Improves null handling in doc importer.

Resolves https://ceapex.visualstudio.com/Engineering/_workitems/edit/183262

1 files changed, 4 insertions, 2 deletions

diff --git a/mdoc/Mono.Documentation/Updater/DocUtils.cs b/mdoc/Mono.Documentation/Updater/DocUtils.cs
index 4e47a3f4..8af7befd 100644
--- a/mdoc/Mono.Documentation/Updater/DocUtils.cs
+++ b/mdoc/Mono.Documentation/Updater/DocUtils.cs
@@ -270,12 +270,14 @@ namespace Mono.Documentation.Updater
                 bool removed = true;

                 foreach (var nchild in n.ChildNodes.Cast<XmlNode>().ToArray())

                 {

+                    if (nchild == null) continue;

+

                     if (depth == 0)

                     {

                         // check the first level children to see if there's an incoming node that matches

-                        var avalues = nchild.Attributes.Cast<XmlAttribute>().Select(a => $"@{a.Name}='{a.Value}'").ToArray();

+                        var avalues = nchild.Attributes?.Cast<XmlAttribute>().Select(a => $"@{a.Name}='{a.Value}'").ToArray();

                         var nodexpath = $"./{nchild.Name}";

-                        if (avalues.Length > 0)

+                        if (avalues?.Length > 0)

                             nodexpath += $"[{ string.Join(" AND ", avalues) }]";

                         var incomingEquivalent = incoming.SelectSingleNode(nodexpath);

                         if (incomingEquivalent != null)