Add Parse.Query.and() to request that all queries must match (#367)

* Add Parse.Query.and() to request that all queries must match
* Add test for Parse.Query.and()
* Add integration tests for Parse.Query.and()

Author: gofabian

integration/test/ParseQueryTest.js

@@ -1310,6 +1310,60 @@ describe('Parse Query', () => {
     });
   });
 
+  it('can build AND queries', (done) => {
+    let objects = [];
+    for (let i = 0; i < 10; i++) {
+      let obj = new Parse.Object('BoxedNumber');
+      obj.set({ x: i, and: true });
+      objects.push(obj);
+    }
+    Parse.Object.saveAll(objects).then(() => {
+      let q1 = new Parse.Query('BoxedNumber');
+      q1.equalTo('and', true);
+      q1.greaterThan('x', 2);
+      let q2 = new Parse.Query('BoxedNumber');
+      q2.equalTo('and', true);
+      q2.lessThan('x', 5);
+      let andQuery = Parse.Query.and(q1, q2);
+      return andQuery.find();
+    }).then((results) => {
+      assert.equal(results.length, 2);
+      results.forEach((number) => {
+        assert(number.get('x') > 2 && number.get('x') < 5);
+      });
+      done();
+    }).fail(e => console.log(e));
+  });
+
+  it('can build complex AND queries', (done) => {
+    let objects = [];
+    for (let i = 0; i < 10; i++) {
+      let child = new Parse.Object('Child');
+      child.set('x', i);
+      child.set('and', true);
+      let parent = new Parse.Object('Parent');
+      parent.set('child', child);
+      parent.set('and', true);
+      parent.set('y', i);
+      objects.push(parent);
+    }
+    Parse.Object.saveAll(objects).then(() => {
+      let subQuery = new Parse.Query('Child');
+      subQuery.equalTo('x', 4);
+      subQuery.equalTo('and', true);
+      let q1 = new Parse.Query('Parent');
+      q1.matchesQuery('child', subQuery);
+      let q2 = new Parse.Query('Parent');
+      q2.equalTo('and', true);
+      q2.equalTo('y', 4);
+      let andQuery = new Parse.Query.and(q1, q2);
+      return andQuery.find();
+    }).then((results) => {
+      assert.equal(results.length, 1);
+      done();
+    }).fail(e => console.log(e));
+  });
+
   it('can iterate over results with each', (done) => {
     let items = [];
     for (let i = 0; i < 50; i++) {

src/ParseQuery.js

@@ -46,6 +46,24 @@ function quote(s: string) {
   return '\\Q' + s.replace('\\E', '\\E\\\\E\\Q') + '\\E';
 }
 
+/**
+ * Extracts the class name from queries. If not all queries have the same
+ * class name an error will be thrown.
+ */
+function _getClassNameFromQueries(queries: Array<ParseQuery>): string {
+  var className = null;
+  queries.forEach((q) => {
+    if (!className) {
+      className = q.className;
+    }
+
+    if (className !== q.className) {
+      throw new Error('All queries must be for the same class.');
+    }
+  });
+  return className;
+}
+
 /*
  * Handles pre-populating the result data of a query with select fields,
  * making sure that the data object contains keys for all objects that have
@@ -229,6 +247,21 @@ class ParseQuery {
     return this;
   }
 
+  /**
+   * Adds constraint that all of the passed in queries match.
+   * @method _andQuery
+   * @param {Array} queries
+   * @return {Parse.Query} Returns the query, so you can chain this call.
+   */
+  _andQuery(queries: Array<ParseQuery>): ParseQuery {
+    var queryJSON = queries.map((q) => {
+      return q.toJSON().where;
+    });
+
+    this._where.$and = queryJSON;
+    return this;
+  }
+
   /**
    * Helper for condition queries
    */
@@ -1288,21 +1321,30 @@ class ParseQuery {
    * @return {Parse.Query} The query that is the OR of the passed in queries.
    */
   static or(...queries: Array<ParseQuery>): ParseQuery {
-    var className = null;
-    queries.forEach((q) => {
-      if (!className) {
-        className = q.className;
-      }
-
-      if (className !== q.className) {
-        throw new Error('All queries must be for the same class.');
-      }
-    });
-
+    var className = _getClassNameFromQueries(queries);
     var query = new ParseQuery(className);
     query._orQuery(queries);
     return query;
   }
+
+  /**
+   * Constructs a Parse.Query that is the AND of the passed in queries.  For
+   * example:
+   * <pre>var compoundQuery = Parse.Query.and(query1, query2, query3);</pre>
+   *
+   * will create a compoundQuery that is an and of the query1, query2, and
+   * query3.
+   * @method and
+   * @param {...Parse.Query} var_args The list of queries to AND.
+   * @static
+   * @return {Parse.Query} The query that is the AND of the passed in queries.
+   */
+  static and(...queries: Array<ParseQuery>): ParseQuery {
+    var className = _getClassNameFromQueries(queries);
+    var query = new ParseQuery(className);
+    query._andQuery(queries);
+    return query;
+  }
 }
 
 var DefaultController = {

src/__tests__/ParseQuery-test.js

@@ -883,6 +883,40 @@ describe('ParseQuery', () => {
     });
   });
 
+  it('can combine queries with an AND clause', () => {
+    var q = new ParseQuery('Item');
+    var q2 = new ParseQuery('Purchase');
+    expect(ParseQuery.and.bind(null, q, q2)).toThrow(
+      'All queries must be for the same class.'
+    );
+
+    q2 = new ParseQuery('Item');
+    q.equalTo('size', 'medium');
+    q2.equalTo('size', 'large');
+
+    var mediumOrLarge = ParseQuery.and(q, q2);
+    expect(mediumOrLarge.toJSON()).toEqual({
+      where: {
+        $and: [
+          { size: 'medium' },
+          { size: 'large' }
+        ]
+      }
+    });
+
+    // It removes limits, skips, etc
+    q.limit(10);
+    mediumOrLarge = ParseQuery.and(q, q2);
+    expect(mediumOrLarge.toJSON()).toEqual({
+      where: {
+        $and: [
+          { size: 'medium' },
+          { size: 'large' }
+        ]
+      }
+    });
+  });
+
   it('can get the first object of a query', (done) => {
     CoreManager.setQueryController({
       aggregate() {},