Document that from subquery may be built using eloquent builders (#44705)

Author: axlon

src/Illuminate/Database/Query/Builder.php

@@ -439,7 +439,7 @@ public function distinct()
     /**
      * Set the table which the query is targeting.
      *
-     * @param  \Closure|\Illuminate\Database\Query\Builder|string  $table
+     * @param  \Closure|\Illuminate\Database\Query\Builder|\Illuminate\Database\Eloquent\Builder|string  $table
      * @param  string|null  $as
      * @return $this
      */

tests/Database/DatabaseQueryBuilderTest.php

@@ -5231,6 +5231,18 @@ public function testWhereJsonLengthSqlServer()
         $this->assertEquals([1], $builder->getBindings());
     }
 
+    public function testFrom()
+    {
+        $builder = $this->getBuilder();
+        $builder->from($this->getBuilder()->from('users'), 'u');
+        $this->assertSame('select * from (select * from "users") as "u"', $builder->toSql());
+
+        $builder = $this->getBuilder();
+        $eloquentBuilder = new EloquentBuilder($this->getBuilder());
+        $builder->from($eloquentBuilder->from('users'), 'u');
+        $this->assertSame('select * from (select * from "users") as "u"', $builder->toSql());
+    }
+
     public function testFromSub()
     {
         $builder = $this->getBuilder();