Terraform - schema_test.go - failing test for TestSchemaMap_Diff

test.txt

    "Complex structure with list of computed string should mark root set as computed": {
      Schema: map[string]*Schema{
        "outer": &Schema{
          Type:     TypeSet,
          Optional: true,
          Elem: &Resource{
            Schema: map[string]*Schema{
              "outer_str": &Schema{
                Type:     TypeString,
                Optional: true,
              },
              "inner": &Schema{
                Type:     TypeList,
                Optional: true,
                Elem:     &Schema{Type: TypeString},
              },
            },
          },
          Set: func(v interface{}) int {
            return 1
          },
        },
      },

      State: nil,

      Config: map[string]interface{}{
        "outer": []map[string]interface{}{
          map[string]interface{}{
            "outer_str": "foo",
            "inner":     []interface{}{"${var.bar}"},
          },
        },
      },

      ConfigVariables: map[string]ast.Variable{
        "var.bar": interfaceToVariableSwallowError(config.UnknownVariableValue),
      },

      Diff: &terraform.InstanceDiff{
        Attributes: map[string]*terraform.ResourceAttrDiff{
          "outer.#": &terraform.ResourceAttrDiff{
            Old: "0",
            New: "1",
          },
          "outer.~1.outer_str": &terraform.ResourceAttrDiff{
            Old: "",
            New: "foo",
          },
          "outer.~1.inner.#": &terraform.ResourceAttrDiff{
            Old: "0",
            New: "1",
          },
          "outer.~1.inner.0": &terraform.ResourceAttrDiff{
            Old: "",
            New: "${var.bar}",
          },
        },
      },

      Err: false,
    },