From adfa38baea125012784877045a292d18488638ac Mon Sep 17 00:00:00 2001
From: Loic Nageleisen <loic.nageleisen@gmail.com>
Date: Tue, 21 Nov 2017 11:17:29 +0100
Subject: [PATCH] Add support for DISTINCT

---
 lib/rebel/sql.rb | 7 ++++---
 test/test_raw.rb | 8 ++++++++
 2 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/lib/rebel/sql.rb b/lib/rebel/sql.rb
index 9379fdc..2e2f51d 100644
--- a/lib/rebel/sql.rb
+++ b/lib/rebel/sql.rb
@@ -13,8 +13,9 @@ module Rebel::SQL
     exec(Rebel::SQL.drop_table(table_name))
   end
 
-  def select(*fields, from: nil, where: nil, inner: nil, left: nil, right: nil)
+  def select(*fields, distinct: distinct, from: nil, where: nil, inner: nil, left: nil, right: nil)
     exec(Rebel::SQL.select(*fields,
+                           distinct: distinct,
                            from: from,
                            where: where,
                            inner: inner,
@@ -178,9 +179,9 @@ module Rebel::SQL
       SQL
     end
 
-    def select(*fields, from: nil, where: nil, inner: nil, left: nil, right: nil)
+    def select(*fields, distinct: nil, from: nil, where: nil, inner: nil, left: nil, right: nil)
       raw <<-SQL
-      SELECT #{names(*fields)}
+      SELECT #{distinct ? "DISTINCT #{names(*distinct)}" : names(*fields)}
       #{from?(from)}
       #{inner?(inner)}
       #{left?(left)}
diff --git a/test/test_raw.rb b/test/test_raw.rb
index b19aee1..e938772 100644
--- a/test/test_raw.rb
+++ b/test/test_raw.rb
@@ -109,6 +109,14 @@ class TestRaw < Minitest::Test
     assert_str_equal(Rebel::SQL.select(Rebel::SQL.raw('1')).strip, 'SELECT 1')
   end
 
+  def test_select_distinct
+    assert_str_equal(Rebel::SQL.select(distinct: :bar, from: :foo).gsub(/\s+/, ' ').strip, 'SELECT DISTINCT "bar" FROM "foo"')
+  end
+
+  def test_select_distinct_multiple
+    assert_str_equal(Rebel::SQL.select(distinct: [:bar, :baz], from: :foo).gsub(/\s+/, ' ').strip, 'SELECT DISTINCT "bar", "baz" FROM "foo"')
+  end
+
   def test_nested_select
     assert_str_equal(Rebel::SQL.select(Rebel::SQL.raw('*'), from: Rebel::SQL.name(:foo), where: Rebel::SQL.name(:bar).in(Rebel::SQL.select(Rebel::SQL.name(:bar), from: Rebel::SQL.name(:foo)))).gsub(/\s+/, ' ').strip, 'SELECT * FROM "foo" WHERE "bar" IN ( SELECT "bar" FROM "foo" )')
   end