Conditionals feature (#2830)

Introduces conditional styling feature.

src/plugins/condition/utils/evaluator.js

@@ -0,0 +1,54 @@
+/*****************************************************************************
+ * Open MCT, Copyright (c) 2014-2020, United States Government
+ * as represented by the Administrator of the National Aeronautics and Space
+ * Administration. All rights reserved.
+ *
+ * Open MCT is licensed under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * http://www.apache.org/licenses/LICENSE-2.0.
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ * Open MCT includes source code licensed under additional open source
+ * licenses. See the Open Source Licenses file (LICENSES.md) included with
+ * this source code distribution or the Licensing information page available
+ * at runtime from the About dialog for additional information.
+ *****************************************************************************/
+
+export const computeCondition = (resultMap, allMustBeTrue) => {
+    let result = false;
+    for (let key in resultMap) {
+        if (resultMap.hasOwnProperty(key)) {
+            result = resultMap[key];
+            if (allMustBeTrue && !result) {
+                //If we want all conditions to be true, then even one negative result should break.
+                break;
+            } else if (!allMustBeTrue && result) {
+                //If we want at least one condition to be true, then even one positive result should break.
+                break;
+            }
+        }
+    }
+    return result;
+};
+
+//Returns true only if limit number of results are satisfied
+export const computeConditionByLimit = (resultMap, limit) => {
+    let trueCount = 0;
+    for (let key in resultMap) {
+        if (resultMap.hasOwnProperty(key)) {
+            if (resultMap[key]) {
+                trueCount++;
+            }
+            if (trueCount > limit) {
+                break;
+            }
+        }
+    }
+    return trueCount === limit;
+};