fix(migrations): expose knex.schema via this.schema

all migrations schemas now can access knex.schema via this.schema

src/Migrations/Mixins/Migrate.js

@@ -105,6 +105,7 @@ Migrate._schemaCallback = function (callback) {
  */
 Migrate._decorateSchema = function (schemaInstance) {
   schemaInstance.fn = this.database.fn
+  schemaInstance.schema = this.database.schema
 }
 
 /**

test/unit/migrations.spec.js

@@ -570,4 +570,22 @@ describe('Migrations', function () {
     expect(accountsTable).deep.equal({})
     yield runner.database.schema.dropTable('adonis_migrations')
   })
+
+  it('should have access to knex schema inside the schema class', function * () {
+    const Runner = new Migrations(Database, Config)
+    const runner = new Runner()
+    let schema = null
+    class Users extends Schema {
+      up () {
+        this.table('users', (table) => {
+          schema = this.schema
+        })
+      }
+    }
+    const migrations = {'2015-01-20': Users}
+    yield runner.up(migrations)
+    expect(schema).to.be.an('object')
+    expect(schema.raw).to.be.a('function')
+    yield runner.database.schema.dropTable('adonis_migrations')
+  })
 })