From 845d09f37ed78902e4495ff3b609b2ff8e08e1fa Mon Sep 17 00:00:00 2001
From: Mat Fish <matanya@daneltech.com>
Date: Mon, 21 Nov 2022 16:39:47 +0200
Subject: [PATCH] add existence filters :tada:

---
 CHANGELOG.md                          |  4 ++++
 README.md                             | 18 ++++++++++++++++++
 src/behaviors/ActiveQueryBehavior.php | 19 ++++++++++++++++++-
 3 files changed, 40 insertions(+), 1 deletion(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index e9f44cc..4554e2c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,9 @@
 # Release Notes for Entry Meta
 
+## 3.1.0 - 2022-11-21
+### Added
+- Added existence filters
+
 ## 3.0.2 - 2022-08-31
 ### Fixed
 - Fixed validation message
diff --git a/README.md b/README.md
index 357d7f4..e5919c2 100644
--- a/README.md
+++ b/README.md
@@ -104,6 +104,7 @@ Or using Twig:
 You can query by metadata on the active record class (e.g `craft\records\Entry`) using the following methods:
 
 #### Filter by metadata
+##### Value
 ```php
 Entry::find()->whereMetadata('foo','bar');
 ```
@@ -113,6 +114,23 @@ The method defaults to the `=` operand, which you can override on the third argu
 ```php
 Entry::find()->whereMetadata('views',0,'>');
 ```
+##### Existence
+You can also check for existence of metadata **keys**:
+```php
+Entry::find()->hasMetadata('foo');
+```
+Or, conversely:
+```php
+Entry::find()->doesntHaveMetadata('foo');
+```
+To filter down by the existence of metadata itself, simply omit the key argument:
+```php
+Entry::find()->hasMetadata(); 
+```
+or
+```php
+Entry::find()->doesntHaveMetadata(); 
+```
 #### Sort by metadata
 ```php
 Entry::find()->whereMetadata('views',0,'>')->orderByMetadata('views',false, true);
diff --git a/src/behaviors/ActiveQueryBehavior.php b/src/behaviors/ActiveQueryBehavior.php
index f9351ae..b1bd617 100644
--- a/src/behaviors/ActiveQueryBehavior.php
+++ b/src/behaviors/ActiveQueryBehavior.php
@@ -45,6 +45,14 @@ public function orderByMetadata($key, $asc = true, $numeric = false)
         return $this->owner->orderBy([$keyExpression => $dir]);
     }
 
+    public function hasMetadata($key = null) {
+        return $this->_whereMetadata($key,null,' IS NOT ','where');
+    }
+
+    public function doesntHaveMetadata($key = null) {
+        return $this->_whereMetadata($key,null,' IS ','where');
+    }
+
     private function _whereMetadata($key, $value, $operand, $method)
     {
         return $this->owner->{$method}($this->_getCondition($key, $value, $operand));
@@ -75,9 +83,14 @@ private function _getCondition($key, $value, $operand): string
         }
     }
 
-    private function _getKeyExpression($key, $cast = null)
+    private function _getKeyExpression($key, $cast = null): string
     {
         $column = EntryMeta::COLUMN_NAME;
+
+        if (is_null($key)) {
+            return $column;
+        }
+
         $Key = $this->_transformKey($key);
 
         if ($this->dbDriver === self::MYSQL) {
@@ -99,6 +112,10 @@ private function _getKeyExpression($key, $cast = null)
 
     private function _transformValue($value)
     {
+        if (is_null($value)) {
+            return 'NULL';
+        }
+
         if (is_bool($value)) {
             return $value ? 'true' : 'false';
         }