Allow empty contact objects

According to the spec the contact object can be empty (it doesn't have
any required properties). Previously, the markup generation failed in
that situation due to an empty paragraph being generated. This change
fixes that.

src/main/java/io/github/swagger2markup/internal/document/builder/OverviewDocumentBuilder.java

@@ -115,7 +115,7 @@ public class OverviewDocumentBuilder extends MarkupDocumentBuilder {
     }
 
     private void buildContactInfoSection(Contact contact) {
-        if(contact != null){
+        if(contact != null && (isNotBlank(contact.getName()) || isNotBlank(contact.getEmail()))){
             this.markupDocBuilder.sectionTitleLevel2(CONTACT_INFORMATION);
             MarkupDocBuilder paragraph = copyMarkupDocBuilder();
             if(isNotBlank(contact.getName())){

src/test/java/io/github/swagger2markup/AsciidocConverterTest.java

@@ -549,4 +549,27 @@ public class AsciidocConverterTest {
         Path expectedFilesDirectory = Paths.get(AsciidocConverterTest.class.getResource("/expected/asciidoc/response_headers").toURI());
         DiffUtils.assertThatAllFilesAreEqual(expectedFilesDirectory, outputDirectory, "testSwagger2AsciiDocConversionWithResponseHeaders.html");
     }
+
+    @Test
+    public void testSwagger2AsciiDocConversionWithEmptyContactUsingJSON() throws IOException, URISyntaxException {
+        //Given
+        Path file = Paths.get(AsciidocConverterTest.class.getResource("/json/swagger_emptycontact.json").toURI());
+        Path outputDirectory = Paths.get("build/test/asciidoc/emptycontact");
+        FileUtils.deleteQuietly(outputDirectory.toFile());
+
+        //When
+        Swagger2MarkupConfig config = new Swagger2MarkupConfigBuilder()
+                .build();
+        Swagger2MarkupConverter.from(file)
+                .withConfig(config)
+                .build()
+                .toFolder(outputDirectory);
+
+        //Then
+        String[] files = outputDirectory.toFile().list();
+        assertThat(files).hasSize(4).containsAll(expectedFiles);
+
+        Path expectedFilesDirectory = Paths.get(AsciidocConverterTest.class.getResource("/expected/asciidoc/emptycontact").toURI());
+        DiffUtils.assertThatAllFilesAreEqual(expectedFilesDirectory, outputDirectory, "testSwagger2AsciiDocConversionWithEmptyContactUsingJSON.html");
+    }
 }

src/test/resources/expected/asciidoc/emptycontact/definitions.adoc

@@ -0,0 +1,2 @@
+
+

src/test/resources/expected/asciidoc/emptycontact/overview.adoc

@@ -0,0 +1,12 @@
+= Empty Contact
+
+
+[[_overview]]
+== Overview
+
+=== Version information
+[%hardbreaks]
+_Version_ : 1.0
+
+
+

src/test/resources/expected/asciidoc/emptycontact/paths.adoc

@@ -0,0 +1,2 @@
+
+

src/test/resources/expected/asciidoc/emptycontact/security.adoc

@@ -0,0 +1,2 @@
+
+

src/test/resources/json/swagger_emptycontact.json

@@ -0,0 +1,9 @@
+{
+  "swagger": "2.0",
+  "info": {
+    "title": "Empty Contact",
+    "contact": {},
+    "version": "1.0"
+  },
+  "paths": {}
+}