From c59df914c1f544889eafc4d8aa64132ae1337102 Mon Sep 17 00:00:00 2001
From: Nikolay <np25071984@gmail.com>
Date: Thu, 10 Jan 2019 17:17:37 +0300
Subject: [PATCH] Fixes #16253: Fixed empty checkboxlist validation

---
 framework/CHANGELOG.md             |  1 +
 framework/assets/yii.activeForm.js | 51 +++++++++++++++++++++++---------------
 2 files changed, 32 insertions(+), 20 deletions(-)

diff --git a/framework/CHANGELOG.md b/framework/CHANGELOG.md
index 4758b37..e13c657 100644
--- a/framework/CHANGELOG.md
+++ b/framework/CHANGELOG.md
@@ -4,6 +4,7 @@ Yii Framework 2 Change Log
 2.0.16 under development
 ------------------------
 
+- Bug #16253: Fixed empty checkboxlist validation (GHopperMSK)
 - Bug #15286: Fixed incorrect formatting of time with timezone information (rugabarbo)
 - Bug #17021: Fix to do not remove existing message category files in a subfolder (albertborsos)
 - Bug #16991: Removed usage of `utf8_encode()` from `Request::resolvePathInfo()` (GHopperMSK)
diff --git a/framework/assets/yii.activeForm.js b/framework/assets/yii.activeForm.js
index fbcece4..4f79b77 100644
--- a/framework/assets/yii.activeForm.js
+++ b/framework/assets/yii.activeForm.js
@@ -325,27 +325,39 @@
             // client-side validation
             $.each(data.attributes, function () {
                 this.$form = $form;
-                if (!findInput($form, this).is(":disabled")) {
-                    this.cancelled = false;
-                    // perform validation only if the form is being submitted or if an attribute is pending validation
-                    if (data.submitting || this.status === 2 || this.status === 3) {
-                        var msg = messages[this.id];
-                        if (msg === undefined) {
-                            msg = [];
-                            messages[this.id] = msg;
+                let $input = findInput($form, this);
+
+                if ($input.is(":disabled")) {
+                    return true;
+                }
+                // pass SELECT without options
+                if ($input.length && $input[0].tagName.toLowerCase() === 'select') {
+                    if (!$input[0].options.length) {
+                        return true;
+                    } else if (($input[0].options.length === 1) && ($input[0].options[0].value === '')) {
+                        return true;
+                    }
+                }
+                this.cancelled = false;
+                // perform validation only if the form is being submitted or if an attribute is pending validation
+                if (data.submitting || this.status === 2 || this.status === 3) {
+                    var msg = messages[this.id];
+                    if (msg === undefined) {
+                        msg = [];
+                        messages[this.id] = msg;
+                    }
+
+                    var event = $.Event(events.beforeValidateAttribute);
+                    $form.trigger(event, [this, msg, deferreds]);
+                    if (event.result !== false) {
+                        if (this.validate) {
+                            this.validate(this, getValue($form, this), msg, deferreds, $form);
                         }
-                        var event = $.Event(events.beforeValidateAttribute);
-                        $form.trigger(event, [this, msg, deferreds]);
-                        if (event.result !== false) {
-                            if (this.validate) {
-                                this.validate(this, getValue($form, this), msg, deferreds, $form);
-                            }
-                            if (this.enableAjaxValidation) {
-                                needAjaxValidation = true;
-                            }
-                        } else {
-                            this.cancelled = true;
+                        if (this.enableAjaxValidation) {
+                            needAjaxValidation = true;
                         }
+                    } else {
+                        this.cancelled = true;
                     }
                 }
             });
@@ -406,7 +418,6 @@
         submitForm: function () {
             var $form = $(this),
                 data = $form.data('yiiActiveForm');
-
             if (data.validated) {
                 // Second submit's call (from validate/updateInputs)
                 data.submitting = false;