SERVER-9406 treat ObjectId type as Date in aggregation date expressions

Closes #1154

Signed-off-by: Charlie Swanson <charlie.swanson@mongodb.com>

1 files changed, 98 insertions, 0 deletions

diff --git a/jstests/aggregation/expressions/object_ids_for_date_expressions.js b/jstests/aggregation/expressions/object_ids_for_date_expressions.js
new file mode 100644
index 00000000000..dae3ce0d280
--- /dev/null
+++ b/jstests/aggregation/expressions/object_ids_for_date_expressions.js
@@ -0,0 +1,98 @@
+// SERVER-9406: Allow ObjectId type to be treated as a date in date related expressions
+
+(function() {
+    "use strict";
+
+    load('jstests/libs/dateutil.js');
+
+    const coll = db.server9406;
+    let testOpCount = 0;
+
+    coll.drop();
+
+    // Seed collection so that the pipeline will execute.
+    assert.writeOK(coll.insert({}));
+
+    function makeObjectIdFromDate(dt) {
+        try {
+            return new ObjectId((dt.getTime() / 1000).toString(16) + "f000000000000000");
+        } catch (e) {
+            assert("Invalid date for conversion to Object Id: " + dt);
+        }
+    }
+
+    /**
+     *  Helper for testing that 'op' on 'value' is the same for dates as equivalent ObjectIds
+     *  'value' is either a date value, or an object containing field 'date'.
+     */
+    function testOp(op, value) {
+        testOpCount++;
+
+        let pipeline = [{$project: {_id: 0, result: {}}}];
+        pipeline[0].$project.result[op] = value;
+        let res1 = coll.aggregate(pipeline).toArray()[0];
+        if (value.date) {
+            value.date = makeObjectIdFromDate(value.date);
+        } else {
+            value = makeObjectIdFromDate(value);
+        }
+        pipeline[0].$project.result[op] = value;
+        let res2 = coll.aggregate(pipeline).toArray()[0];
+
+        assert.eq(res2.result, res1.result, tojson(pipeline));
+    }
+
+    testOp('$dateToString', {date: new Date("1980-12-31T23:59:59Z"), format: "%V-%G"});
+    testOp('$dateToString', {date: new Date("1980-12-31T23:59:59Z"), format: "%G-%V"});
+
+    const years = [
+        2002,  // Starting and ending on Tuesday.
+        2014,  // Starting and ending on Wednesday.
+        2015,  // Starting and ending on Thursday.
+        2010,  // Starting and ending on Friday.
+        2011,  // Starting and ending on Saturday.
+        2006,  // Starting and ending on Sunday.
+        1996,  // Starting on Monday, ending on Tuesday.
+        2008,  // Starting on Tuesday, ending on Wednesday.
+        1992,  // Starting on Wednesday, ending on Thursday.
+        2004,  // Starting on Thursday, ending on Friday.
+        2016,  // Starting on Friday, ending on Saturday.
+        2000,  // Starting on Saturday, ending on Sunday (special).
+        2012   // Starting on Sunday, ending on Monday.
+    ];
+
+    const day = 1;
+    years.forEach(function(year) {
+        // forEach starts indexing at zero but weekdays start with Monday on 1 so we add +1.
+        let newYear = DateUtil.getNewYear(year);
+        let endOfFirstWeekInYear = DateUtil.getEndOfFirstWeekInYear(year, day);
+        let startOfSecondWeekInYear = DateUtil.getStartOfSecondWeekInYear(year, day);
+        let birthday = DateUtil.getBirthday(year);
+        let newYearsEve = DateUtil.getNewYearsEve(year);
+        let now = new Date();
+        now.setYear(year);
+        now.setMilliseconds(0);
+
+        testOp('$isoDayOfWeek', newYear);
+        testOp('$isoDayOfWeek', endOfFirstWeekInYear);
+        testOp('$isoDayOfWeek', startOfSecondWeekInYear);
+        testOp('$isoWeekYear', birthday);
+
+        testOp('$isoWeek', newYear);
+        testOp('$isoWeek', now);
+        testOp('$isoWeekYear', newYear);
+        testOp('$isoWeek', endOfFirstWeekInYear);
+        testOp('$dateToString', {format: '%G-W%V-%u', date: newYear});
+        testOp('$isoWeek', endOfFirstWeekInYear);
+        testOp('$year', endOfFirstWeekInYear);
+        testOp('$month', endOfFirstWeekInYear);
+        testOp('$dayOfMonth', endOfFirstWeekInYear);
+        testOp('$dayOfWeek', birthday);
+        testOp('$dayOfWeek', newYearsEve);
+        testOp('$minute', newYearsEve);
+        testOp('$second', now);
+        testOp('$millisecond', newYear);
+
+    });
+    assert.eq(testOpCount, 236, 'Expected 236 tests to run');
+})();