From f55c1de20cd674ced7dc9a9cd4c218bc8cedaa64 Mon Sep 17 00:00:00 2001
From: Konstantin Dudkov <kdudkov@ya.ru>
Date: Thu, 21 Nov 2019 15:48:15 +0300
Subject: [PATCH] add relative key link for ConflictsWith field

---
 helper/schema/schema.go      | 12 +++++-
 helper/schema/schema_test.go | 77 ++++++++++++++++++++++++++++++++++++
 2 files changed, 87 insertions(+), 2 deletions(-)

diff --git a/helper/schema/schema.go b/helper/schema/schema.go
index c6061da9ee0..8d39f143fa1 100644
--- a/helper/schema/schema.go
+++ b/helper/schema/schema.go
@@ -1466,20 +1466,28 @@ func validateConflictingAttributes(
 	}
 
 	for _, conflictingKey := range schema.ConflictsWith {
-		if raw, ok := c.Get(conflictingKey); ok {
+		resolvedKey := resolveKey(k, conflictingKey)
+		if raw, ok := c.Get(resolvedKey); ok {
 			if raw == hcl2shim.UnknownVariableValue {
 				// An unknown value might become unset (null) once known, so
 				// we must defer validation until it's known.
 				continue
 			}
 			return fmt.Errorf(
-				"%q: conflicts with %s", k, conflictingKey)
+				"%q: conflicts with %s", k, resolvedKey)
 		}
 	}
 
 	return nil
 }
 
+func resolveKey(rootKey string, key string) string {
+	if strings.HasPrefix(key, "..") && strings.Contains(rootKey, ".") {
+		return rootKey[:strings.LastIndex(rootKey, ".")+1] + key[2:]
+	}
+	return key
+}
+
 func removeDuplicates(elements []string) []string {
 	encountered := make(map[string]struct{}, 0)
 	result := []string{}
diff --git a/helper/schema/schema_test.go b/helper/schema/schema_test.go
index b14e61d218e..b808c401d14 100644
--- a/helper/schema/schema_test.go
+++ b/helper/schema/schema_test.go
@@ -4907,6 +4907,83 @@ func TestSchemaMap_Validate(t *testing.T) {
 			},
 		},
 
+		"Conflicting subelements": {
+			Schema: map[string]*Schema{
+				"items": &Schema{
+					Type:     TypeList,
+					Required: true,
+					Elem: &Resource{
+						Schema: map[string]*Schema{
+							"blacklist": &Schema{
+								Type:          TypeString,
+								Optional:      true,
+								ConflictsWith: []string{"..greenlist"},
+							},
+							"greenlist": &Schema{
+								Type:          TypeString,
+								Optional:      true,
+								ConflictsWith: []string{"..blacklist"},
+							},
+						},
+					},
+				},
+			},
+
+			Config: map[string]interface{}{
+				"items": []interface{}{
+					map[string]interface{}{
+						"blacklist": "black-val",
+						"greenlist": "green-val",
+					},
+					map[string]interface{}{
+						"blacklist": "black-val",
+					},
+				},
+			},
+
+			Err: true,
+			Errors: []error{
+				fmt.Errorf("\"items.0.blacklist\": conflicts with items.0.greenlist"),
+				fmt.Errorf("\"items.0.greenlist\": conflicts with items.0.blacklist"),
+			},
+		},
+
+		"Non-conflicting subelements": {
+			Schema: map[string]*Schema{
+				"items": &Schema{
+					Type:     TypeList,
+					Required: true,
+					Elem: &Resource{
+						Schema: map[string]*Schema{
+							"blacklist": &Schema{
+								Type:          TypeString,
+								Optional:      true,
+								ConflictsWith: []string{"..greenlist"},
+							},
+							"greenlist": &Schema{
+								Type:          TypeString,
+								Optional:      true,
+								ConflictsWith: []string{"..blacklist"},
+							},
+						},
+					},
+				},
+			},
+
+			Config: map[string]interface{}{
+				"items": []interface{}{
+					map[string]interface{}{
+						"greenlist": "green-val",
+					},
+					map[string]interface{}{
+						"blacklist": "black-val",
+					},
+				},
+			},
+
+			Err: false,
+		},
+
 		"Required attribute & undefined conflicting optional are good": {
 			Schema: map[string]*Schema{
 				"required_att": &Schema{