[10.x] Database Expressions that are conditions (#47210)

* expressions that form a complete condition

* style-ci

* formatting

---------

Co-authored-by: Taylor Otwell <taylor@laravel.com>

src/Illuminate/Contracts/Database/Query/ConditionExpression.php

@@ -0,0 +1,7 @@
+<?php
+
+namespace Illuminate\Contracts\Database\Query;
+
+interface ConditionExpression extends Expression
+{
+}

src/Illuminate/Database/Query/Builder.php

@@ -7,6 +7,7 @@
 use Closure;
 use DateTimeInterface;
 use Illuminate\Contracts\Database\Query\Builder as BuilderContract;
+use Illuminate\Contracts\Database\Query\ConditionExpression;
 use Illuminate\Contracts\Database\Query\Expression as ExpressionContract;
 use Illuminate\Contracts\Support\Arrayable;
 use Illuminate\Database\Concerns\BuildsQueries;
@@ -753,6 +754,14 @@ public function mergeWheres($wheres, $bindings)
      */
     public function where($column, $operator = null, $value = null, $boolean = 'and')
     {
+        if ($column instanceof ConditionExpression) {
+            $type = 'Expression';
+
+            $this->wheres[] = compact('type', 'column', 'boolean');
+
+            return $this;
+        }
+
         // If the column is an array, we will assume it is an array of key-value pairs
         // and can add them each as a where clause. We will maintain the boolean we
         // received when the method was called and pass it into the nested where.
@@ -2083,6 +2092,14 @@ public function having($column, $operator = null, $value = null, $boolean = 'and
     {
         $type = 'Basic';
 
+        if ($column instanceof ConditionExpression) {
+            $type = 'Expression';
+
+            $this->havings[] = compact('type', 'column', 'boolean');
+
+            return $this;
+        }
+
         // Here we will make some assumptions about the operator. If only 2 values are
         // passed to the method, we will assume that the operator is an equals sign
         // and keep going. Otherwise, we'll require the operator to be passed in.

src/Illuminate/Database/Query/Grammars/Grammar.php

@@ -706,6 +706,18 @@ public function whereFullText(Builder $query, $where)
         throw new RuntimeException('This database engine does not support fulltext search operations.');
     }
 
+    /**
+     * Compile a clause based on an expression.
+     *
+     * @param  \Illuminate\Database\Query\Builder  $query
+     * @param  array  $where
+     * @return string
+     */
+    public function whereExpression(Builder $query, $where)
+    {
+        return $where['column']->getValue($this);
+    }
+
     /**
      * Compile the "group by" portions of the query.
      *
@@ -752,6 +764,8 @@ protected function compileHaving(array $having)
             return $this->compileHavingNotNull($having);
         } elseif ($having['type'] === 'bit') {
             return $this->compileHavingBit($having);
+        } elseif ($having['type'] === 'Expression') {
+            return $this->compileHavingExpression($having);
         } elseif ($having['type'] === 'Nested') {
             return $this->compileNestedHavings($having);
         }
@@ -834,6 +848,17 @@ protected function compileHavingBit($having)
         return '('.$column.' '.$having['operator'].' '.$parameter.') != 0';
     }
 
+    /**
+     * Compile a having clause involving an expression.
+     *
+     * @param  array  $having
+     * @return string
+     */
+    protected function compileHavingExpression($having)
+    {
+        return $having['column']->getValue($this);
+    }
+
     /**
      * Compile a nested having clause.
      *

tests/Database/DatabaseQueryBuilderTest.php

@@ -5,6 +5,7 @@
 use BadMethodCallException;
 use Closure;
 use DateTime;
+use Illuminate\Contracts\Database\Query\ConditionExpression;
 use Illuminate\Database\ConnectionInterface;
 use Illuminate\Database\Eloquent\Builder as EloquentBuilder;
 use Illuminate\Database\Query\Builder;
@@ -1833,6 +1834,22 @@ public function testHavingNotNull()
         $this->assertSame('select "category", count(*) as "total" from "item" where "department" = ? group by "category" having "total" is not null', $builder->toSql());
     }
 
+    public function testHavingExpression()
+    {
+        $builder = $this->getBuilder();
+        $builder->select('*')->from('users')->having(
+            new class() implements ConditionExpression
+            {
+                public function getValue(\Illuminate\Database\Grammar $grammar)
+                {
+                    return '1 = 1';
+                }
+            }
+        );
+        $this->assertSame('select * from "users" having 1 = 1', $builder->toSql());
+        $this->assertSame([], $builder->getBindings());
+    }
+
     public function testHavingShortcut()
     {
         $builder = $this->getBuilder();
@@ -5076,6 +5093,22 @@ public function testCursorPaginateWithUnionWheresMultipleOrders()
         ]), $result);
     }
 
+    public function testWhereExpression()
+    {
+        $builder = $this->getBuilder();
+        $builder->select('*')->from('orders')->where(
+            new class() implements ConditionExpression
+            {
+                public function getValue(\Illuminate\Database\Grammar $grammar)
+                {
+                    return '1 = 1';
+                }
+            }
+        );
+        $this->assertSame('select * from "orders" where 1 = 1', $builder->toSql());
+        $this->assertSame([], $builder->getBindings());
+    }
+
     public function testWhereRowValues()
     {
         $builder = $this->getBuilder();