fix crash on invalid cref

Author: saucecontrol

src/InheritDoc/InheritDoc.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
 	<PropertyGroup>
-		<VersionPrefix>2.0.1</VersionPrefix>
+		<VersionPrefix>2.0.2</VersionPrefix>
 		<TargetFrameworks>netstandard2.0</TargetFrameworks>
 	</PropertyGroup>
 
@@ -21,14 +21,14 @@
 
 	<ItemGroup>
 		<PackageReference Include="Microsoft.Build.Utilities.Core" Version="16.0.461" />
-		<PackageReference Include="Mono.Cecil" Version="0.11.5" PrivateAssets="all" />
+		<PackageReference Include="Mono.Cecil" Version="0.11.6" PrivateAssets="all" />
 		<!-- these are for use in the test project, downloaded here to avoid version conflicts when building tests -->
 		<PackageDownload Include="Microsoft.NETCore.App.Ref" Version="[7.0.0]" />
 		<PackageDownload Include="Microsoft.NETFramework.ReferenceAssemblies.net48" Version="[1.0.0]" />
 	</ItemGroup>
 
 	<Target Name="VerifyPackDependencies" BeforeTargets="GenerateNuspec">
-		<Error Condition="@(None->WithMetadataValue('Pack', 'true')->WithMetadataValue('Filename', 'Mono.Cecil')->Count()) != 1" Text="Dependencies were not present for pack. Start build again." />
+		<Error Condition="@(None-&gt;WithMetadataValue('Pack', 'true')-&gt;WithMetadataValue('Filename', 'Mono.Cecil')-&gt;Count()) != 1" Text="Dependencies were not present for pack. Start build again." />
 	</Target>
 
 </Project>

src/InheritDoc/InheritDocProcessor.cs

@@ -94,7 +94,7 @@ static XDocument loadDoc(string path)
 		;
 
 		var docMap = generateDocMap(types, docMembers, trimLevel, logger);
-		var docCref = docMembers.Elements(DocElementNames.Member).Where(m => !m.HasAttribute(DocAttributeNames._trimmed)).Descendants(DocElementNames.InheritDoc).Select(i => (string)i.Attribute(DocAttributeNames.Cref)).Where(c => !string.IsNullOrWhiteSpace(c));
+		var docCref = docMembers.Elements(DocElementNames.Member).Where(m => !m.HasAttribute(DocAttributeNames._trimmed)).Descendants(DocElementNames.InheritDoc).Select(i => (string)i.Attribute(DocAttributeNames.Cref)).Where(isValidCref);
 		var asmTypes = types.Select(t => t.GetDocID()).ToHashSet();
 
 		var refCref = docMap.Values.SelectMany(v => v.Select(l => l.Cref)).Concat(docCref).Where(c => !asmTypes.Contains(getTypeIDFromDocID(c))).ToHashSet();
@@ -171,7 +171,7 @@ private static IDictionary<string, IEnumerable<DocMatch>> generateDocMap(IList<T
 			{
 				logger.Write(ILogger.Severity.Diag, "Processing DocID: " + typeID);
 
-				var crefs = typeDocs.Descendants(DocElementNames.InheritDoc).Select(i => (string)i.Attribute(DocAttributeNames.Cref)).Where(c => !string.IsNullOrWhiteSpace(c)).ToList();
+				var crefs = typeDocs.Descendants(DocElementNames.InheritDoc).Select(i => (string)i.Attribute(DocAttributeNames.Cref)).Where(isValidCref).ToList();
 				var dml = new List<DocMatch>();
 				docMap.Add(typeID, dml);
 
@@ -267,7 +267,7 @@ private static IDictionary<string, IEnumerable<DocMatch>> generateDocMap(IList<T
 						logger.Write(ILogger.Severity.Diag, "Processing DocID: " + memID);
 
 						var bases = (om is not null ? (new[] { om }) : []).Concat(m.GetBaseCandidates()).ToList();
-						var crefs = methDocs.Descendants(DocElementNames.InheritDoc).Select(i => (string)i.Attribute(DocAttributeNames.Cref)).Where(c => !string.IsNullOrWhiteSpace(c)).ToHashSet();
+						var crefs = methDocs.Descendants(DocElementNames.InheritDoc).Select(i => (string)i.Attribute(DocAttributeNames.Cref)).Where(isValidCref).ToHashSet();
 						var dml = new List<DocMatch>();
 
 						foreach (var (bm, cref) in bases.SelectMany(bm => bm.GetDocID().Select(d => (bm, d))))
@@ -555,6 +555,8 @@ static XDocument getRefDocs(IReadOnlyCollection<string> refAssemblies, IReadOnly
 		}
 	}
 
+	private static bool isValidCref(string cref) => cref is { Length: > 2 } && cref[0] is not '!' && (cref[0] is 'T' || cref.IndexOf('.', 2) > 0);
+
 	private static string getTypeIDFromDocID(string docID)
 	{
 		if (docID[0] == 'T')

tests/InheritDoc.Test/InheritDoc.Test.csproj

@@ -7,9 +7,9 @@
 	</PropertyGroup>
 
 	<ItemGroup>
-		<PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.8.0" />
-		<PackageReference Include="MSTest.TestAdapter" Version="3.2.0" />
-		<PackageReference Include="MSTest.TestFramework" Version="3.2.0" />
+		<PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.11.1" />
+		<PackageReference Include="MSTest.TestAdapter" Version="3.6.1" />
+		<PackageReference Include="MSTest.TestFramework" Version="3.6.1" />
 	</ItemGroup>
 
 	<ItemGroup>