tests: add tests for hidden variables

internal/orchestrator/app/validator_test.go

@@ -33,6 +33,21 @@ func TestValidateAppDescriptorBricks(t *testing.T) {
 					},
 				},
 			},
+			{
+				ID:   "arduino:brick-with-hidden-variable",
+				Name: "Hidden variable brick",
+				Variables: []bricksindex.BrickVariable{
+					{
+						Name:   "I_AM_HIDDEN_WITHOUT_DEFAULT",
+						Hidden: true,
+					},
+					{
+						Name:         "I_AM_HIDDEN_WITH_DEFAULT",
+						Hidden:       true,
+						DefaultValue: "default-value",
+					},
+				},
+			},
 		},
 	}
 
@@ -134,6 +149,26 @@ bricks:
         NOT_EXISTING_VARIABLE: "this-is-a-not-existing-variable-for-the-brick"
         ARDUINO_DEVICE_ID: "my-device-id"
         ARDUINO_SECRET: "my-secret"
+`,
+			expectedError: nil,
+		},
+		{
+			name: "is required works also for hidden variables",
+			yamlContent: `
+name: App with
+bricks:
+  - arduino:brick-with-hidden-variable:
+`,
+			expectedError: errors.New("variable \"I_AM_HIDDEN_WITHOUT_DEFAULT\" is required by brick \"arduino:brick-with-hidden-variable\""),
+		},
+		{
+			name: "an hiddden variable with default value is not required",
+			yamlContent: `
+name: App with
+bricks:
+  - arduino:brick-with-hidden-variable:
+  	  variables:
+        I_AM_HIDDEN_WITHOUT_DEFAULT: "some-value"
 `,
 			expectedError: nil,
 		},