TimedImagePreviewStrategy.createPreview(): add unit test.

Fix #581

No functional changes.

Author: php-coder

src/test/groovy/ru/mystamps/web/service/TimedImagePreviewStrategyTest.groovy

@@ -0,0 +1,61 @@
+/**
+ * Copyright (C) 2009-2017 Slava Semushin <slava.semushin@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+package ru.mystamps.web.service
+
+import org.slf4j.helpers.NOPLogger
+
+import spock.lang.Specification
+import spock.lang.Unroll
+
+@SuppressWarnings(['ClassJavadoc', 'MethodName', 'NoDef', 'NoTabCharacter', 'TrailingWhitespace'])
+class TimedImagePreviewStrategyTest extends Specification {
+	
+	private final ImagePreviewStrategy origStrategy = Mock()
+	
+	private ImagePreviewStrategy strategy
+	
+	def setup() {
+		strategy = new TimedImagePreviewStrategy(NOPLogger.NOP_LOGGER, origStrategy)
+	}
+	
+	//
+	// Tests for createPreview()
+	//
+	
+	@Unroll
+	@SuppressWarnings(['ClosureAsLastMethodParameter', 'FactoryMethodName', 'UnnecessaryReturnKeyword'])
+	def 'createPreview() should pass #expectedData and return result of original strategy'(byte[] expectedData) {
+		given:
+			byte[] expectedResult = 'foobar'.bytes
+		when:
+			byte[] result = strategy.createPreview(expectedData)
+		then:
+			1 * origStrategy.createPreview({ byte[] image ->
+				image == expectedData
+			return true
+			}) >> expectedResult
+		and:
+			result == expectedResult
+		where:
+			expectedData | _
+			null         | _
+			'foo'.bytes  | _
+		
+	}
+	
+}