Add a test to ensure packaging is preserved during model merging in SmartModelMerger

Author: gastaldi

src/test/approvals/io/fabric8/maven/merge/SmartModelMergerTest.should_preserve_packaging.approved.txt

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd" xmlns="http://maven.apache.org/POM/4.0.0"
+    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
+  <modelVersion>4.0.0</modelVersion>
+  <groupId>org.acme</groupId>
+  <artifactId>my-app</artifactId>
+  <version>1.0.0-SNAPSHOT</version>
+  <packaging>quarkus</packaging>
+  <properties>
+    <property-from-extension>value</property-from-extension>
+  </properties>
+</project>

src/test/java/io/fabric8/maven/merge/SmartModelMergerTest.java

@@ -2,6 +2,8 @@
 
 import static org.assertj.core.api.Assertions.assertThat;
 
+import java.io.StringReader;
+import java.io.StringWriter;
 import java.net.URISyntaxException;
 import java.nio.file.Path;
 import java.nio.file.Paths;
@@ -117,4 +119,30 @@ void should_keep_target_indent_4() throws URISyntaxException {
         Approvals.verify(targetFile.toFile());
     }
 
+    @Test
+    void should_preserve_packaging() {
+        String basePom = "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n" +
+                "<project>\n" +
+                "    <modelVersion>4.0.0</modelVersion>\n" +
+                "    <groupId>org.acme</groupId>\n" +
+                "    <artifactId>my-app</artifactId>\n" +
+                "    <version>1.0.0-SNAPSHOT</version>\n" +
+                "    <packaging>quarkus</packaging>\n" +
+                "</project>\n";
+
+        String extensionPom = "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n" +
+                "<project>\n" +
+                "    <properties>\n" +
+                "        <property-from-extension>value</property-from-extension>\n" +
+                "    </properties>\n" +
+                "</project>\n";
+
+        ModelMerger merger = new SmartModelMerger();
+        final Model source = Maven.readModel(new StringReader(basePom));
+        final Model target = Maven.readModel(new StringReader(extensionPom));
+        merger.merge(target, source, true, null);
+        StringWriter writer = new StringWriter();
+        Maven.writeModel(target, writer);
+        Approvals.verify(writer.toString());
+    }
 }