From b02e1c7bc6baeea04bf43c6ec1a586c37ba47c99 Mon Sep 17 00:00:00 2001
From: Danis Kirasirov <dbgbbu@gmail.com>
Date: Mon, 29 Jan 2024 15:05:23 +0300
Subject: [PATCH] =?UTF-8?q?=D0=A0=D0=B5=D1=84=D0=B0=D0=BA=D1=82=D0=BE?=
=?UTF-8?q?=D1=80=D0=B8=D0=BD=D0=B3=20=D0=BE=D0=B1=D1=80=D0=B0=D0=B1=D0=BE?=
=?UTF-8?q?=D1=82=D0=BA=D0=B8=20=D1=84=D1=83=D0=BD=D0=BA=D1=86=D0=B8=D0=B8?=
=?UTF-8?q?=20len?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
---
pkg/expr/mongo.go | 96 +++++++++++++++++++++++++-----------------
pkg/expr/mongo_test.go | 2 +-
2 files changed, 59 insertions(+), 39 deletions(-)
diff --git a/pkg/expr/mongo.go b/pkg/expr/mongo.go
index 3cdbf045..de14bb57 100644
--- a/pkg/expr/mongo.go
+++ b/pkg/expr/mongo.go
@@ -231,19 +231,12 @@ func (c *compiler) identifier(node ast.Node) string {
}
func (c *compiler) BinaryNode(node *ast.BinaryNode) interface{} {
+ if result, ok := c.handleLenNode(node); ok {
+ return result
+ }
+
switch node.Operator {
case "==":
- op := c.eval(node.Right)
- lenNode, ok := node.Left.(*ast.BuiltinNode)
- if ok && lenNode.Name == "len" && len(lenNode.Arguments) == 1 {
- // Оптимизация для случая len(arr) == 0, т.к. $size не использует индекс
- if op == 0 {
- return bson.M{c.identifier(lenNode.Arguments[0]): bson.M{"$eq": bson.A{}}}
- }
-
- return bson.M{c.identifier(lenNode.Arguments[0]): bson.M{"$size": op}}
- }
-
return bson.M{c.identifier(node.Left): c.eval(node.Right)}
case "!=":
@@ -262,36 +255,10 @@ func (c *compiler) BinaryNode(node *ast.BinaryNode) interface{} {
return bson.M{c.identifier(node.Left): bson.M{"$nin": c.eval(node.Right)}}
case "<":
- op := c.eval(node.Right)
- lenNode, ok := node.Left.(*ast.BuiltinNode)
- if ok && lenNode.Name == "len" && len(lenNode.Arguments) == 1 {
- length, ok := op.(int)
- if !ok {
- panic("len must be compared with an integer")
- }
- return bson.M{c.identifier(lenNode.Arguments[0]) + "." + strconv.Itoa(length): bson.M{"$exists": false}}
- }
-
return bson.M{c.identifier(node.Left): bson.M{"$lt": c.eval(node.Right)}}
case ">":
- op := c.eval(node.Right)
- lenNode, ok := node.Left.(*ast.BuiltinNode)
- if ok && lenNode.Name == "len" && len(lenNode.Arguments) == 1 {
- length, ok := op.(int)
- if !ok {
- panic("len must be compared with an integer")
- }
-
- // Оптимизация для случая len(arr) > 0
- if length == 0 {
- return bson.M{c.identifier(lenNode.Arguments[0]): bson.M{"$exists": true, "$type": "array", "$ne": bson.A{}}}
- }
-
- return bson.M{c.identifier(lenNode.Arguments[0]) + "." + strconv.Itoa(length): bson.M{"$exists": true}}
- }
-
- return bson.M{c.identifier(node.Left): bson.M{"$gt": op}}
+ return bson.M{c.identifier(node.Left): bson.M{"$gt": c.eval(node.Right)}}
case "<=":
return bson.M{c.identifier(node.Left): bson.M{"$lte": c.eval(node.Right)}}
@@ -688,3 +655,56 @@ func (c *compiler) PairNode(node *ast.PairNode) interface{} {
//c.compile(node.Key)
//c.compile(node.Value)
}
+
+func (c *compiler) handleLenNode(node *ast.BinaryNode) (result bson.M, ok bool) {
+ lenNode, ok := node.Left.(*ast.BuiltinNode)
+ if !ok || lenNode.Name != "len" {
+ return nil, false
+ }
+
+ if len(lenNode.Arguments) != 1 {
+ panic("len() expects exactly 1 argument")
+ }
+
+ length, ok := c.eval(node.Right).(int)
+ if !ok || length < 0 {
+ panic("len() can only be compared with non-negative number")
+ }
+
+ switch node.Operator {
+ case "==": // +
+ if length == 0 {
+ return bson.M{c.identifier(lenNode.Arguments[0]): bson.M{"$eq": bson.A{}}}, true
+ }
+ return bson.M{c.identifier(lenNode.Arguments[0]): bson.M{"$size": length}}, true
+
+ case "!=": // +
+ if length == 0 {
+ return bson.M{c.identifier(lenNode.Arguments[0]): bson.M{"$exists": true, "$type": "array", "$ne": bson.A{}}}, true
+ }
+ return bson.M{c.identifier(lenNode.Arguments[0]): bson.M{"$not": bson.M{"$size": length}}}, true
+
+ case ">": // +
+ if length == 0 {
+ return bson.M{c.identifier(lenNode.Arguments[0]): bson.M{"$exists": true, "$type": "array", "$ne": bson.A{}}}, true
+ }
+ return bson.M{c.identifier(lenNode.Arguments[0]) + "." + strconv.Itoa(length): bson.M{"$exists": true}}, true
+
+ case ">=":
+ if length == 0 {
+ return bson.M{c.identifier(lenNode.Arguments[0]): bson.M{"$exists": true, "$type": "array"}}, true
+ }
+ return bson.M{c.identifier(lenNode.Arguments[0]) + "." + strconv.Itoa(length-1): bson.M{"$exists": true}}, true
+
+ case "<":
+ if length == 0 {
+ panic("invalid comparison: len() cannot be less than 0")
+ }
+ return bson.M{c.identifier(lenNode.Arguments[0]) + "." + strconv.Itoa(length-1): bson.M{"$exists": false}}, true
+
+ case "<=":
+ return bson.M{c.identifier(lenNode.Arguments[0]) + "." + strconv.Itoa(length): bson.M{"$exists": false}}, true
+ }
+
+ panic("invalid comparison operator with len()")
+}
diff --git a/pkg/expr/mongo_test.go b/pkg/expr/mongo_test.go
index c8f8d4ba..ae6bee16 100644
--- a/pkg/expr/mongo_test.go
+++ b/pkg/expr/mongo_test.go
@@ -35,7 +35,7 @@ func TestConvertToMongo(t *testing.T) {
{"len equal empty", "len(s) == 0", nil, bson.M{"s": bson.M{"$eq": bson.A{}}}, false},
{"len gt", "len(s) > 1", nil, bson.M{"s.1": bson.M{"$exists": true}}, false},
{"len gt 0", "len(s) > 0", nil, bson.M{"s": bson.M{"$exists": true, "$type": "array", "$ne": bson.A{}}}, false},
- {"len lt", "len(s) < 1", nil, bson.M{"s.1": bson.M{"$exists": false}}, false},
+ {"len lt", "len(s) < 1", nil, bson.M{"s.0": bson.M{"$exists": false}}, false},
{"field#1", "s.test > 3", nil, bson.M{"s.test": bson.M{"$gt": 3}}, false},
{"field#2", "s['test'] > 3", nil, bson.M{"s.test": bson.M{"$gt": 3}}, false},
{"field#3", "s[test] > 3", nil, bson.M{"s.test": bson.M{"$gt": 3}}, false},
--
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