terraform: interpolation failures on a destroy provisioner should error

terraform/context_apply_test.go

@@ -4771,6 +4771,61 @@ func TestContext2Apply_provisionerDestroyRef(t *testing.T) {
 	}
 }
 
+// Test that a destroy provisioner referencing an invalid key errors.
+func TestContext2Apply_provisionerDestroyRefInvalid(t *testing.T) {
+	m := testModule(t, "apply-provisioner-destroy-ref")
+	p := testProvider("aws")
+	pr := testProvisioner()
+	p.ApplyFn = testApplyFn
+	p.DiffFn = testDiffFn
+	pr.ApplyFn = func(rs *InstanceState, c *ResourceConfig) error {
+		return nil
+	}
+
+	state := &State{
+		Modules: []*ModuleState{
+			&ModuleState{
+				Path: rootModulePath,
+				Resources: map[string]*ResourceState{
+					"aws_instance.bar": &ResourceState{
+						Type: "aws_instance",
+						Primary: &InstanceState{
+							ID: "bar",
+						},
+					},
+
+					"aws_instance.foo": &ResourceState{
+						Type: "aws_instance",
+						Primary: &InstanceState{
+							ID: "bar",
+						},
+					},
+				},
+			},
+		},
+	}
+
+	ctx := testContext2(t, &ContextOpts{
+		Module:  m,
+		State:   state,
+		Destroy: true,
+		Providers: map[string]ResourceProviderFactory{
+			"aws": testProviderFuncFixed(p),
+		},
+		Provisioners: map[string]ResourceProvisionerFactory{
+			"shell": testProvisionerFuncFixed(pr),
+		},
+	})
+
+	if _, err := ctx.Plan(); err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	if _, err := ctx.Apply(); err == nil {
+		t.Fatal("expected error")
+	}
+}
+
 func TestContext2Apply_provisionerResourceRef(t *testing.T) {
 	m := testModule(t, "apply-provisioner-resource-ref")
 	p := testProvider("aws")

terraform/interpolate.go

@@ -498,7 +498,7 @@ MISSING:
 	//
 	// For an input walk, computed values are okay to return because we're only
 	// looking for missing variables to prompt the user for.
-	if i.Operation == walkRefresh || i.Operation == walkPlanDestroy || i.Operation == walkDestroy || i.Operation == walkInput {
+	if i.Operation == walkRefresh || i.Operation == walkPlanDestroy || i.Operation == walkInput {
 		return &unknownVariable, nil
 	}