added unit test for mustache compile to find mismatched braces and tags (#94)

Author: ddsharpe

imagetool/src/test/java/com/oracle/weblogic/imagetool/util/DockerfileBuilderTest.java

@@ -0,0 +1,53 @@
+// Copyright (c) 2019, Oracle Corporation and/or its affiliates.  All rights reserved.
+// Licensed under the Universal Permissive License v 1.0 as shown at https://oss.oracle.com/licenses/upl.
+
+package com.oracle.weblogic.imagetool.util;
+
+import java.io.File;
+import java.io.IOException;
+import java.io.StringWriter;
+import java.util.Arrays;
+
+import com.github.mustachejava.DefaultMustacheFactory;
+import com.github.mustachejava.Mustache;
+import com.github.mustachejava.MustacheFactory;
+import com.oracle.weblogic.imagetool.api.model.DomainType;
+import org.junit.Test;
+
+import static org.junit.Assert.assertTrue;
+
+public class DockerfileBuilderTest {
+
+    /**
+     * Catch mismatched start/end tags and missing mustache braces.
+     * @throws IOException if file read fails for mustache file.
+     */
+    @Test
+    public void validateMustacheAliases() throws IOException {
+        DockerfileOptions dockerfileOptions = new DockerfileOptions()
+            .setPatchingEnabled()
+            .setOPatchPatchingEnabled()
+            .setWdtEnabled()
+            .setWdtDomainType(DomainType.WLS)
+            .setWdtModels(Arrays.asList("model1.yaml", "model2.yaml"))
+            .setPackageInstaller(Constants.YUM);
+
+        MustacheFactory mf = new DefaultMustacheFactory(new File("src/main/resources/docker-files"));
+        Mustache mustache = mf.compile("Create_Image.mustache");
+        //mustache.execute(new PrintWriter(System.out), dockerfileOptions).flush();
+        mustache.execute(new StringWriter(), dockerfileOptions).flush();
+        assertTrue(true);
+    }
+
+    @Test
+    public void setPackageInstaller() {
+        DockerfileOptions options = new DockerfileOptions().setPackageInstaller(Constants.YUM);
+        assertTrue("Failed to set YUM installer", options.useYum);
+
+        options = new DockerfileOptions().setPackageInstaller(Constants.APTGET);
+        assertTrue("Failed to set 'APTGET' installer", options.useAptGet);
+
+        options = new DockerfileOptions().setPackageInstaller(Constants.ZYPPER);
+        assertTrue("Failed to set 'ZYPPER' installer", options.useZypper);
+    }
+}