Added create/drop trigger dialect conditions (vapor#169)

* Added create/drop trigger dialect conditions

* Uses new trigger dialect syntax

* Fixes casing on an option name

* Style changes requested by Tanner

Author: grosch

Sources/PostgresKit/PostgresDialect.swift

@@ -9,10 +9,6 @@ public struct PostgresDialect: SQLDialect {
         return SQLRaw("\"")
     }
 
-    public var literalStringQuote: SQLExpression {
-        return SQLRaw("'")
-    }
-
     public func bindPlaceholder(at position: Int) -> SQLExpression {
         return SQLRaw("$" + position.description)
     }
@@ -37,4 +33,11 @@ public struct PostgresDialect: SQLDialect {
     public var enumSyntax: SQLEnumSyntax {
         .typeName
     }
+
+    public var triggerSyntax: SQLTriggerSyntax {
+        return .init(
+            create: [.supportsForEach, .postgreSQLChecks, .supportsCondition, .conditionRequiresParentheses, .supportsConstraints],
+            drop: [.supportsCascade, .supportsTableName]
+        )
+    }
 }

docker-compose.yml

@@ -1,35 +1,24 @@
-version: '2'
+version: '3.7'
 
-services:
-  psql-11:
-    image: postgres:11
-    environment:
+x-common: &common
+  environment:
       POSTGRES_USER: vapor_username
       POSTGRES_DB: vapor_database
       POSTGRES_PASSWORD: vapor_password
-    ports:
-      - 5432:5432
+  ports:
+    - 5432:5432
+
+services:
+  psql-11:
+    <<: *common
+    image: postgres:11
   psql-10:
+    <<: *common
     image: postgres:10
-    environment:
-      POSTGRES_USER: vapor_username
-      POSTGRES_DB: vapor_database
-      POSTGRES_PASSWORD: vapor_password
-    ports:
-      - 5432:5432
   psql-9:
+    <<: *common
     image: postgres:9
-    environment:
-      POSTGRES_USER: vapor_username
-      POSTGRES_DB: vapor_database
-      POSTGRES_PASSWORD: vapor_password
-    ports:
-      - 5432:5432
   psql-ssl:
+    <<: *common
     image: scenecheck/postgres-ssl:latest
-    environment:
-      POSTGRES_USER: vapor_username
-      POSTGRES_DB: vapor_database
-      POSTGRES_PASSWORD: vapor_password
-    ports:
-      - 5432:5432
+