Initial QSfera import

Server/vendor/github.com/open-policy-agent/opa/internal/merge/merge.go

@@ -0,0 +1,64 @@
+// Copyright 2017 The OPA Authors.  All rights reserved.
+// Use of this source code is governed by an Apache2
+// license that can be found in the LICENSE file.
+
+// Package merge contains helpers to merge data structures
+// frequently encountered in OPA.
+package merge
+
+// InterfaceMaps returns the result of merging a and b. If a and b cannot be
+// merged because of conflicting key-value pairs, ok is false.
+func InterfaceMaps(a map[string]any, b map[string]any) (map[string]any, bool) {
+
+	if a == nil {
+		return b, true
+	}
+
+	if hasConflicts(a, b) {
+		return nil, false
+	}
+
+	return merge(a, b), true
+}
+
+func merge(a, b map[string]any) map[string]any {
+
+	for k := range b {
+
+		add := b[k]
+		exist, ok := a[k]
+		if !ok {
+			a[k] = add
+			continue
+		}
+
+		existObj := exist.(map[string]any)
+		addObj := add.(map[string]any)
+
+		a[k] = merge(existObj, addObj)
+	}
+
+	return a
+}
+
+func hasConflicts(a, b map[string]any) bool {
+	for k := range b {
+
+		add := b[k]
+		exist, ok := a[k]
+		if !ok {
+			continue
+		}
+
+		existObj, existOk := exist.(map[string]any)
+		addObj, addOk := add.(map[string]any)
+		if !existOk || !addOk {
+			return true
+		}
+
+		if hasConflicts(existObj, addObj) {
+			return true
+		}
+	}
+	return false
+}