From 99225b8d76c0df3faf063618b4600ce7aacec0eb Mon Sep 17 00:00:00 2001
From: Kristin Laemmert <mildwonkey@users.noreply.github.com>
Date: Mon, 25 Nov 2019 15:01:38 -0500
Subject: [PATCH] command/jsonstate,plan: fix panic with null values (#23492)

The code responsible for marshalling attribute values was checking for
nil values, but not null.

Fixes #23485, #23274
---
 command/jsonplan/values.go      |  2 +-
 command/jsonplan/values_test.go | 12 ++++++++++++
 command/jsonstate/state.go      |  3 ++-
 command/jsonstate/state_test.go | 12 ++++++++++++
 4 files changed, 27 insertions(+), 2 deletions(-)

diff --git a/command/jsonplan/values.go b/command/jsonplan/values.go
index 498b0f6f7..caa8babf4 100644
--- a/command/jsonplan/values.go
+++ b/command/jsonplan/values.go
@@ -26,7 +26,7 @@ type stateValues struct {
 type attributeValues map[string]interface{}
 
 func marshalAttributeValues(value cty.Value, schema *configschema.Block) attributeValues {
-	if value == cty.NilVal {
+	if value == cty.NilVal || value.IsNull() {
 		return nil
 	}
 	ret := make(attributeValues)
diff --git a/command/jsonplan/values_test.go b/command/jsonplan/values_test.go
index 6b04dba02..8395ee0aa 100644
--- a/command/jsonplan/values_test.go
+++ b/command/jsonplan/values_test.go
@@ -30,6 +30,18 @@ func TestMarshalAttributeValues(t *testing.T) {
 			},
 			nil,
 		},
+		{
+			cty.NullVal(cty.String),
+			&configschema.Block{
+				Attributes: map[string]*configschema.Attribute{
+					"foo": {
+						Type:     cty.String,
+						Optional: true,
+					},
+				},
+			},
+			nil,
+		},
 		{
 			cty.ObjectVal(map[string]cty.Value{
 				"foo": cty.StringVal("bar"),
diff --git a/command/jsonstate/state.go b/command/jsonstate/state.go
index 1923c6468..2fac8fbba 100644
--- a/command/jsonstate/state.go
+++ b/command/jsonstate/state.go
@@ -101,9 +101,10 @@ type resource struct {
 type attributeValues map[string]interface{}
 
 func marshalAttributeValues(value cty.Value, schema *configschema.Block) attributeValues {
-	if value == cty.NilVal {
+	if value == cty.NilVal || value.IsNull() {
 		return nil
 	}
+
 	ret := make(attributeValues)
 
 	it := value.ElementIterator()
diff --git a/command/jsonstate/state_test.go b/command/jsonstate/state_test.go
index f03dd2d45..e40c123c6 100644
--- a/command/jsonstate/state_test.go
+++ b/command/jsonstate/state_test.go
@@ -91,6 +91,18 @@ func TestMarshalAttributeValues(t *testing.T) {
 			},
 			nil,
 		},
+		{
+			cty.NullVal(cty.String),
+			&configschema.Block{
+				Attributes: map[string]*configschema.Attribute{
+					"foo": {
+						Type:     cty.String,
+						Optional: true,
+					},
+				},
+			},
+			nil,
+		},
 		{
 			cty.ObjectVal(map[string]cty.Value{
 				"foo": cty.StringVal("bar"),