A few small bugfixes discovered from online users of openapi-changes

someone caused a panic, exposed an untested bug.

Signed-off-by: quobix <dave@quobix.com>

datamodel/low/extraction_functions.go

@@ -823,6 +823,9 @@ func AreEqual(l, r Hashable) bool {
 	if l == nil || r == nil {
 		return false
 	}
+	if reflect.ValueOf(l).IsNil() || reflect.ValueOf(r).IsNil() {
+		return false
+	}
 	return l.Hash() == r.Hash()
 }
 

datamodel/low/v3/paths.go

@@ -154,7 +154,7 @@ func (p *Paths) Build(ctx context.Context, _, root *yaml.Node, idx *index.SpecIn
 			err := path.Build(ctx, cNode, pNode, idx)
 
 			if err != nil {
-				if idx.GetLogger() != nil {
+				if idx != nil && idx.GetLogger() != nil {
 					idx.GetLogger().Error(fmt.Sprintf("error building path item '%s'", err.Error()))
 				}
 				//return buildResult{}, err

what-changed/model/paths.go

@@ -146,12 +146,17 @@ func ComparePaths(l, r any) *PathsChanges {
 
 		lKeys := make(map[string]low.ValueReference[*v3.PathItem])
 		rKeys := make(map[string]low.ValueReference[*v3.PathItem])
+
+		if lPath != nil {
 			for k := range lPath.PathItems {
 				lKeys[k.Value] = lPath.PathItems[k]
 			}
+		}
+		if rPath != nil {
 			for k := range rPath.PathItems {
 				rKeys[k.Value] = rPath.PathItems[k]
 			}
+		}
 
 		// run every comparison in a thread.
 		var mLock sync.Mutex
@@ -199,7 +204,15 @@ func ComparePaths(l, r any) *PathsChanges {
 			pc.PathItemsChanges = pathChanges
 		}
 
-		pc.ExtensionChanges = CompareExtensions(lPath.Extensions, rPath.Extensions)
+		var lExt, rExt map[low.KeyReference[string]]low.ValueReference[any]
+		if lPath != nil {
+			lExt = lPath.Extensions
+		}
+		if rPath != nil {
+			rExt = rPath.Extensions
+		}
+
+		pc.ExtensionChanges = CompareExtensions(lExt, rExt)
 	}
 	pc.PropertyChanges = NewPropertyChanges(changes)
 	return pc