Introduce date histogram time base configuration to EditorConfig (#22344)

* Add `default` and `baseInterval` configuration ability to date histogram EditorConfig
* Change EditorConfig `warning` to `help`, show `help` below date histogram and histogram interval inputs

packages/kbn-datemath/package.json

@@ -5,8 +5,9 @@
   "license": "Apache-2.0",
   "private": true,
   "main": "target/index.js",
+  "typings": "target/index.d.ts",
   "scripts": {
-    "build": "babel src --out-dir target",
+    "build": "babel src --out-dir target --copy-files",
     "kbn:bootstrap": "yarn build",
     "kbn:watch": "yarn build --watch"
   },

packages/kbn-datemath/src/index.d.ts

@@ -0,0 +1,29 @@
+/*
+ * Licensed to Elasticsearch B.V. under one or more contributor
+ * license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright
+ * ownership. Elasticsearch B.V. licenses this file to you 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.
+ */
+
+declare module '@kbn/datemath' {
+  const dateMath: {
+    parse: any;
+    unitsMap: any;
+    units: string[];
+    unitsAsc: string[];
+    unitsDesc: string[];
+  };
+  export default dateMath;
+}

packages/kbn-datemath/src/index.js

@@ -19,9 +19,20 @@
 
 import moment from 'moment';
 
-const units = ['y', 'M', 'w', 'd', 'h', 'm', 's', 'ms'];
-const unitsDesc = units;
-const unitsAsc = [...unitsDesc].reverse();
+const unitsMap = {
+  ms: { weight: 1, type: 'fixed', base: 1 },
+  s: { weight: 2, type: 'fixed', base: 1000 },
+  m: { weight: 3, type: 'mixed', base: 1000 * 60 },
+  h: { weight: 4, type: 'mixed', base: 1000 * 60 * 60 },
+  d: { weight: 5, type: 'mixed', base: 1000 * 60 * 60 * 24 },
+  w: { weight: 6, type: 'calendar' },
+  M: { weight: 7, type: 'calendar' },
+  // q: { weight: 8, type: 'calendar' }, // TODO: moment duration does not support quarter
+  y: { weight: 9, type: 'calendar' },
+};
+const units = Object.keys(unitsMap).sort((a, b) => unitsMap[b].weight - unitsMap[a].weight);
+const unitsDesc = [...units];
+const unitsAsc = [...units].reverse();
 
 const isDate = d => Object.prototype.toString.call(d) === '[object Date]';
 
@@ -142,6 +153,7 @@ function parseDateMath(mathString, time, roundUp) {
 
 export default {
   parse: parse,
+  unitsMap: Object.freeze(unitsMap),
   units: Object.freeze(units),
   unitsAsc: Object.freeze(unitsAsc),
   unitsDesc: Object.freeze(unitsDesc),

packages/kbn-datemath/tsconfig.json

@@ -0,0 +1,10 @@
+{
+  "extends": "../../tsconfig.json",
+  "compilerOptions": {
+    "declaration": true,
+    "outDir": "./target"
+  },
+  "include": [
+    "./src/**/*.ts"
+  ]
+}