feat: add warning when int value is too large during upload

src/entity.ts

@@ -579,7 +579,16 @@ export namespace entity {
     }
 
     if (typeof value === 'number') {
-      if (value % 1 === 0) {
+      if (Number.isInteger(value)) {
+        if (!Number.isSafeInteger(value)) {
+          process.emitWarning(
+            'Integer value ' +
+              value +
+              ' is outside of bounds of a JavaScript Number\n' +
+              "Use 'Datastore.int(<integer_value_as_string>)' to preserve accuracy during the upload.",
+            'IntegerOutOfBoundsWarning'
+          );
+        }
         value = new entity.Int(value);
       } else {
         value = new entity.Double(value);

system-test/datastore.ts

@@ -246,6 +246,17 @@ describe('Datastore', () => {
       await datastore.delete(postKey);
     });
 
+    it('should accurately save/get a large int value via Datastore.int()', async () => {
+      const postKey = datastore.key('Team');
+      const largeIntValueAsString = '9223372036854775807';
+      const points = Datastore.int(largeIntValueAsString);
+      await datastore.save({key: postKey, data: {points}});
+      const [entity] = await datastore.get(postKey, {wrapNumbers: true});
+      assert.strictEqual(entity.points.value, largeIntValueAsString);
+      assert.throws(() => entity.points.valueOf());
+      await datastore.delete(postKey);
+    });
+
     it('should save/get/delete with a key name', async () => {
       const postKey = datastore.key(['Post', 'post1']);
       await datastore.save({key: postKey, data: post});

test/entity.ts

@@ -777,6 +777,22 @@ describe('entity', () => {
       assert.deepStrictEqual(entity.encodeValue(value), expectedValueProto);
     });
 
+    it('should emit warning on out of bounce int', done => {
+      const largeIntValue = 9223372036854775807;
+      const expectedWarning =
+        'Integer value ' +
+        largeIntValue +
+        ' is outside of bounds of a JavaScript Number\n' +
+        "Use 'Datastore.int(<integer_value_as_string>)' to preserve accuracy during the upload.";
+
+      process.on('warning', warning => {
+        assert.strictEqual(warning.name, 'IntegerOutOfBoundsWarning');
+        assert.strictEqual(warning.message, expectedWarning);
+        done();
+      });
+      entity.encodeValue(largeIntValue);
+    });
+
     it('should encode an Int object', () => {
       const value = new entity.Int(3);