diff --git a/packages/google-cloud-ndb/.coveragerc b/packages/google-cloud-ndb/.coveragerc
index 7d18616a6f3f..f3d727c18756 100644
--- a/packages/google-cloud-ndb/.coveragerc
+++ b/packages/google-cloud-ndb/.coveragerc
@@ -2,13 +2,20 @@
 branch = True
 
 [report]
-fail_under = 99
+fail_under = 100
 show_missing = True
 exclude_lines =
     # Re-enable the standard pragma
     pragma: NO COVER
+    # Ignore debug-only repr
+    def __repr__
+    # Ignore abstract methods
+    raise NotImplementedError
+    # Ignore defensive assertions
+    raise TypeError
 omit =
   .nox/*
   */gapic/*.py
   */proto/*.py
-  tests/*/*.py
+  tests/*
+  */tests/*
diff --git a/packages/google-cloud-ndb/tests/unit/test__gql.py b/packages/google-cloud-ndb/tests/unit/test__gql.py
index 430ca5ea10e5..71b51636411f 100644
--- a/packages/google-cloud-ndb/tests/unit/test__gql.py
+++ b/packages/google-cloud-ndb/tests/unit/test__gql.py
@@ -715,3 +715,17 @@ def test_user():
     def test_nop():
         with pytest.raises(NotImplementedError):
             gql_module.FUNCTIONS["nop"]("any arg")
+
+    @staticmethod
+    def test_time_2_args_and_invalid():
+        import datetime
+
+        assert gql_module._time_function([10, 30]) == datetime.time(10, 30)
+        with pytest.raises(exceptions.BadQueryError):
+            gql_module._time_function([])
+
+    @staticmethod
+    def test_ancestor_condition_not_is():
+        gql = gql_module.GQL("SELECT * FROM Kind")
+        with pytest.raises(ValueError, match="condition must be 'is'"):
+            gql._AddProcessedParameterFilter("ancestor", "!=", "nop", ["param"])
diff --git a/packages/google-cloud-ndb/tests/unit/test_model.py b/packages/google-cloud-ndb/tests/unit/test_model.py
index cb6af3f042d7..6b5e3fbbc059 100644
--- a/packages/google-cloud-ndb/tests/unit/test_model.py
+++ b/packages/google-cloud-ndb/tests/unit/test_model.py
@@ -6658,3 +6658,17 @@ class ManyFields(model.Model):
         unused = model.FloatProperty()
 
     return ManyFields
+
+
+def test_model_set_projection_branches():
+    class Child(model.Model):
+        val = model.StringProperty()
+
+    class Parent(model.Model):
+        child = model.StructuredProperty(Child)
+        children = model.StructuredProperty(Child, repeated=True)
+
+    parent = Parent(child=Child(val="a"), children=[Child(val="b")])
+    parent._set_projection(["child.val", "children.val", "nonexistent.subprop"])
+    parent._properties = None
+    parent._set_projection(["child.val"])