entc/predicate: add isnull/notnull predicates for codegen

Reviewed By: idoshveki

Differential Revision: D16687226

fbshipit-source-id: 14a39e066447dbf77413e5c7f7318a2d61bddd32

dialect/gremlin/graph/dsl/__/dsl.go

@@ -14,6 +14,9 @@ func Not(args ...interface{}) *dsl.Traversal { return New().Not(args...) }
 // Has is the api for calling __.Has().
 func Has(args ...interface{}) *dsl.Traversal { return New().Has(args...) }
 
+// HasNot is the api for calling __.HasNot().
+func HasNot(args ...interface{}) *dsl.Traversal { return New().HasNot(args...) }
+
 // Or is the api for calling __.Or().
 func Or(args ...interface{}) *dsl.Traversal { return New().Or(args...) }
 

dialect/gremlin/graph/dsl/dsl_test.go

@@ -130,6 +130,11 @@ func TestTraverse(t *testing.T) {
 			wantQuery: "g.V().count()",
 			wantBinds: dsl.Bindings{},
 		},
+		{
+			input:     g.V().HasNot("age"),
+			wantQuery: "g.V().hasNot($0)",
+			wantBinds: dsl.Bindings{"$0": "age"},
+		},
 		{
 			input: func() *dsl.Traversal {
 				v := g.V().HasID(1)

dialect/gremlin/graph/dsl/traversal.go

@@ -112,6 +112,12 @@ func (t *Traversal) Has(args ...interface{}) *Traversal {
 	return t.Add(Dot, NewFunc("has", args...))
 }
 
+// HasNot filters vertices, edges and vertex properties based on the non-existence of properties.
+// See: http://tinkerpop.apache.org/docs/current/reference/#has-step.
+func (t *Traversal) HasNot(args ...interface{}) *Traversal {
+	return t.Add(Dot, NewFunc("hasNot", args...))
+}
+
 // HasID filters vertices, edges and vertex properties based on their identifier.
 func (t *Traversal) HasID(args ...interface{}) *Traversal {
 	return t.Add(Dot, NewFunc("hasId", args...))

dialect/sql/builder_test.go

@@ -191,6 +191,17 @@ func TestBuilder(t *testing.T) {
 				Where(NotNull("parent_id")),
 			wantQuery: "DELETE FROM `users` WHERE `parent_id` IS NOT NULL",
 		},
+		{
+			input: Delete("users").
+				Where(IsNull("parent_id")),
+			wantQuery: "DELETE FROM `users` WHERE `parent_id` IS NULL",
+		},
+		{
+			input: Delete("users").
+				Where(IsNull("parent_id").And().NotIn("name", "foo", "bar")),
+			wantQuery: "DELETE FROM `users` WHERE `parent_id` IS NULL AND `name` NOT IN (?, ?)",
+			wantArgs:  []interface{}{"foo", "bar"},
+		},
 		{
 			input: Delete("users").
 				Where(False().And().False()),