SERVER-69408 Add randomized testing for the mixed-type timeseries bug

.eslintignore

@@ -1,2 +1,3 @@
 src/mongo/gotools/*
 *.tpl.js
+jstests/third_party/**/*.js

jstests/noPassthroughWithMongod/randomized_mixed_type_bug.js

@@ -0,0 +1,79 @@
+/**
+ * Tests that randomly generated documents can be queried from timeseries collections in the same
+ * manner as a tradional collection.
+ */
+(function() {
+"use strict";
+
+load('jstests/third_party/fast_check/fc-3.1.0.js');  // For fast-check (fc).
+
+const scalars = [fc.string(), fc.double(), fc.boolean(), fc.date(), fc.constant(null)];
+const pathComponents = fc.constant("a", "b");
+// Define our grammar for documents.
+let documentModel = fc.letrec(
+    tie => ({
+        // Our Terminals.
+        scalar: fc.oneof(...scalars),
+        value: fc.oneof(
+            {maxDepth: 3},
+            // It may be surprising that we don't have to reweight this. Oneof handles ensuring the
+            // termination happens (on sequential runs it weights the first option heavier). The
+            // maxDepth parameter also ensures that termination happens by the time the depth is
+            // reached.
+            // Moreover fast-check prefers simpler object to more complex objects on some runs so we
+            // needn't upweight scalars in order to ensure that scalar cases occur more frequently.
+            // For more information about the biases fast-check applies see:
+            // https://github.com/dubzzz/fast-check/blob/main/packages/fast-check/documentation/HowItWorks.md#bias
+            tie('scalar'),
+            tie('object'),
+            fc.array(tie('value'))),
+        object: fc.object({key: pathComponents, maxDepth: 0, maxKeys: 2, values: [tie('value')]}),
+    }));
+
+// Define our test arbitraries
+const onePath = fc.array(pathComponents, {minLength: 1, maxLength: 2});
+const oneComparator = fc.oneof(fc.constant("$lte"), fc.constant("$gte"));
+const atLeastThreeDocs = fc.array(documentModel.object, {minLength: 3});
+
+// Our test case
+let testMixedTypeQuerying = () => {
+    // Assert that query results for ts pushdowns are the same as query results for non-ts
+    // collections.
+    fc.assert(fc.property(
+        // The arbitrary.
+        fc.tuple(atLeastThreeDocs, documentModel.scalar, onePath, oneComparator),
+        // The scenario to test.
+        ([docs, val, pathArray, compare]) => {
+            db.test.drop();
+            db.control.drop();
+            db.createCollection("test", {timeseries: {timeField: "t"}});
+
+            // Insert documents
+            docs.forEach(doc => {
+                let date = new ISODate();
+                db.test.insert(Object.assign({t: date}, doc));
+                db.control.insert(Object.assign({t: date}, doc));
+            });
+
+            // Construct the path to query on.
+            let path = pathArray.join('.');
+
+            // Query on pathArray w/ {[compare]: val} on test and control.
+            // Compare the results.
+            try {
+                assert.docEq(
+                    // Is timeseries.
+                    db.test.find({[path]: {[compare]: val}}, {_id: 0}).toArray(),
+                    // Isn't timeseries.
+                    db.control.find({[path]: {[compare]: val}}, {_id: 0}).toArray());
+                return true;
+            } catch (e) {
+                printjson(
+                    {info: "test failed", error: e, scenario: [docs, val, pathArray, compare]});
+                return false;
+            }
+        }));
+};  // testMixedTypeQuerying
+
+testMixedTypeQuerying();
+})();

jstests/third_party/fast_check/LICENSE

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2017 Nicolas DUBIEN
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

jstests/third_party/fast_check/README.md

@@ -0,0 +1,2 @@
+This directory contains [fast-check](https://github.com/dubzzz/fast-check) version 3.1.0.
+It is provided under the LICENSE provided in the file [LICENSE](LICENSE).