Include root path in directory resolve index (#869)

syft/source/directory_resolver.go

@@ -147,7 +147,7 @@ func (r *directoryResolver) indexPath(path string, info os.FileInfo, err error)
 	}
 
 	// link cycles could cause a revisit --we should not allow this
-	if r.fileTree.HasPath(file.Path(path)) {
+	if r.hasBeenIndexed(path) {
 		return "", nil
 	}
 
@@ -193,6 +193,23 @@ func (r directoryResolver) addPathToIndex(p string, info os.FileInfo) (string, e
 	}
 }
 
+func (r directoryResolver) hasBeenIndexed(p string) bool {
+	filePath := file.Path(p)
+	if !r.fileTree.HasPath(filePath) {
+		return false
+	}
+
+	exists, ref, err := r.fileTree.File(filePath)
+	if err != nil || !exists || ref == nil {
+		return false
+	}
+
+	// cases like "/" will be in the tree, but not been indexed yet (a special case). We want to capture
+	// these cases as new paths to index.
+	_, exists = r.metadata[ref.ID()]
+	return exists
+}
+
 func (r directoryResolver) addDirectoryToIndex(p string, info os.FileInfo) error {
 	ref, err := r.fileTree.AddDir(file.Path(p))
 	if err != nil {

syft/source/directory_resolver_test.go

@@ -848,3 +848,20 @@ func testWithTimeout(t *testing.T, timeout time.Duration, test func(*testing.T))
 	case <-done:
 	}
 }
+
+func Test_IncludeRootPathInIndex(t *testing.T) {
+	filterFn := func(path string, _ os.FileInfo) bool {
+		return path != "/"
+	}
+
+	resolver, err := newDirectoryResolver("/", filterFn)
+	require.NoError(t, err)
+
+	exists, ref, err := resolver.fileTree.File(file.Path("/"))
+	require.NoError(t, err)
+	require.NotNil(t, ref)
+	assert.True(t, exists)
+
+	_, exists = resolver.metadata[ref.ID()]
+	require.True(t, exists)
+}