[11.x] Add ability to create raw unique indexes for postgresql

src/Illuminate/Database/Schema/Blueprint.php

@@ -716,6 +716,18 @@ public function rawIndex($expression, $name)
         return $this->index([new Expression($expression)], $name);
     }
 
+    /**
+     * Specify a raw unique index for the table.
+     *
+     * @param  string  $expression
+     * @param  string  $name
+     * @return \Illuminate\Database\Schema\IndexDefinition
+     */
+    public function rawUnique($expression, $name)
+    {
+        return $this->unique([new Expression($expression)], $name);
+    }
+
     /**
      * Specify a foreign key for the table.
      *

src/Illuminate/Database/Schema/Grammars/PostgresGrammar.php

@@ -314,6 +314,14 @@ public function compilePrimary(Blueprint $blueprint, Fluent $command)
      */
     public function compileUnique(Blueprint $blueprint, Fluent $command)
     {
+        if ($command->useCreateIndex) {
+            return sprintf('create unique index %s on %s (%s)',
+                $this->wrap($command->index),
+                $this->wrapTable($blueprint),
+                $this->columnize($command->columns),
+            );
+        }
+
         $sql = sprintf('alter table %s add constraint %s unique (%s)',
             $this->wrapTable($blueprint),
             $this->wrap($command->index),

src/Illuminate/Database/Schema/IndexDefinition.php

@@ -9,6 +9,7 @@
  * @method $this language(string $language) Specify a language for the full text index (PostgreSQL)
  * @method $this deferrable(bool $value = true) Specify that the unique index is deferrable (PostgreSQL)
  * @method $this initiallyImmediate(bool $value = true) Specify the default time to check the unique index constraint (PostgreSQL)
+ * @method $this useCreateIndex(bool $value = true) Specify if the unique index will be created using CREATE UNIQUE INDEX (PostgreSQL)
  */
 class IndexDefinition extends Fluent
 {

tests/Database/DatabasePostgresSchemaGrammarTest.php

@@ -274,6 +274,16 @@ public function testAddingUniqueKey()
         $this->assertSame('alter table "users" add constraint "bar" unique ("foo")', $statements[0]);
     }
 
+    public function testAddingUniqueKeyViaUseCreateIndex()
+    {
+        $blueprint = new Blueprint('users');
+        $blueprint->unique('foo', 'bar')->useCreateIndex();
+        $statements = $blueprint->toSql($this->getConnection(), $this->getGrammar());
+
+        $this->assertCount(1, $statements);
+        $this->assertSame('create unique index "bar" on "users" ("foo")', $statements[0]);
+    }
+
     public function testAddingIndex()
     {
         $blueprint = new Blueprint('users');
@@ -364,6 +374,26 @@ public function testAddingRawIndex()
         $this->assertSame('create index "raw_index" on "users" ((function(column)))', $statements[0]);
     }
 
+    public function testAddingRawUniqueKey()
+    {
+        $blueprint = new Blueprint('users');
+        $blueprint->rawUnique('foo,bar', 'baz');
+        $statements = $blueprint->toSql($this->getConnection(), $this->getGrammar());
+
+        $this->assertCount(1, $statements);
+        $this->assertSame('alter table "users" add constraint "baz" unique (foo,bar)', $statements[0]);
+    }
+
+    public function testAddingRawUniqueKeyViaUseCreateIndex()
+    {
+        $blueprint = new Blueprint('users');
+        $blueprint->rawUnique('function(column)', 'baz')->useCreateIndex();
+        $statements = $blueprint->toSql($this->getConnection(), $this->getGrammar());
+
+        $this->assertCount(1, $statements);
+        $this->assertSame('create unique index "baz" on "users" (function(column))', $statements[0]);
+    }
+
     public function testAddingIncrementingID()
     {
         $blueprint = new Blueprint('users');