added tests for LoaderOperationPlugin

src/test/groovy/com/github/springfox/loader/plugins/LoaderOperationPluginSpec.groovy

@@ -0,0 +1,63 @@
+package com.github.springfox.loader.plugins
+
+import spock.lang.Specification
+import springfox.documentation.builders.OperationBuilder
+import springfox.documentation.service.Operation
+import springfox.documentation.spi.DocumentationType
+import springfox.documentation.spi.service.contexts.OperationContext
+
+class LoaderOperationPluginSpec extends Specification {
+    private OperationContext context
+    private OperationBuilder builder
+
+    void setup() {
+        builder = Mock(OperationBuilder) {
+            build() >> Mock(Operation) {
+                getSummary() >> 'MyTest'
+            }
+        }
+        context = Mock(OperationContext) {
+            operationBuilder() >> builder
+        }
+    }
+
+    def "Update summary when creating LoaderOperationPlugin with conventionMode enabled"() {
+        when:
+        def plugin = new LoaderOperationPlugin(true)
+        plugin.apply(context)
+
+        then:
+        1 * builder.summary('My test')
+    }
+
+    def "Do not update summary when creating LoaderOperationPlugin with conventionMode disabled"() {
+        when:
+        def plugin = new LoaderOperationPlugin(false)
+        plugin.apply(context)
+
+        then:
+        0 * builder.summary(_ as String)
+    }
+
+    def "Return true on supports swagger 2 documentation type"() {
+        given:
+        def plugin = new LoaderOperationPlugin(true)
+
+        when:
+        def supports = plugin.supports(DocumentationType.SWAGGER_2)
+
+        then:
+        supports
+    }
+
+    def "Return false on supports swagger 1.2 documentation type"() {
+        given:
+        def plugin = new LoaderOperationPlugin(true)
+
+        when:
+        def supports = plugin.supports(DocumentationType.SWAGGER_12)
+
+        then:
+        !supports
+    }
+}