Throw error when failing to find the body element in a document

3 files changed, 38 insertions, 12 deletions

diff --git a/NEWS b/NEWS
index 9977f85..a5855c9 100644
--- a/NEWS
+++ b/NEWS
@@ -2,6 +2,8 @@
 
 * Support attributes in HTML paths in style mappings.
 
+* Throw error when failing to find the body element in a document.
+
 # 1.6.0
 
 * Support merged paragraphs when revisions are tracked.
diff --git a/src/main/java/org/zwobble/mammoth/internal/docx/DocumentXmlReader.java b/src/main/java/org/zwobble/mammoth/internal/docx/DocumentXmlReader.java
index 25855f3..e2db2e7 100644
--- a/src/main/java/org/zwobble/mammoth/internal/docx/DocumentXmlReader.java
+++ b/src/main/java/org/zwobble/mammoth/internal/docx/DocumentXmlReader.java
@@ -5,9 +5,9 @@ import org.zwobble.mammoth.internal.documents.Document;
 import org.zwobble.mammoth.internal.documents.Notes;
 import org.zwobble.mammoth.internal.results.InternalResult;
 import org.zwobble.mammoth.internal.xml.XmlElement;
-import org.zwobble.mammoth.internal.xml.XmlElementLike;
 
 import java.util.List;
+import java.util.Optional;
 
 public class DocumentXmlReader {
     private final BodyXmlReader bodyReader;
@@ -21,8 +21,13 @@ public class DocumentXmlReader {
     }
 
     public InternalResult<Document> readElement(XmlElement element) {
-        XmlElementLike body = element.findChildOrEmpty("w:body");
-        return bodyReader.readElements(body.getChildren())
+        Optional<XmlElement> body = element.findChild("w:body");
+
+        if (!body.isPresent()) {
+            throw new IllegalArgumentException("Could not find the body element: are you sure this is a docx file?");
+        }
+
+        return bodyReader.readElements(body.get().getChildren())
             .toResult()
             .map(children -> new Document(children, notes, comments));
     }
diff --git a/src/test/java/org/zwobble/mammoth/tests/docx/DocumentXmlTests.java b/src/test/java/org/zwobble/mammoth/tests/docx/DocumentXmlTests.java
index 3aa6a62..92674d0 100644
--- a/src/test/java/org/zwobble/mammoth/tests/docx/DocumentXmlTests.java
+++ b/src/test/java/org/zwobble/mammoth/tests/docx/DocumentXmlTests.java
@@ -11,6 +11,7 @@ import org.zwobble.mammoth.internal.xml.XmlElement;
 import org.zwobble.mammoth.internal.xml.XmlNodes;
 
 import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.equalTo;
 import static org.zwobble.mammoth.internal.util.Lists.list;
 import static org.zwobble.mammoth.internal.xml.XmlNodes.element;
 import static org.zwobble.mammoth.tests.DeepReflectionMatcher.deepEquals;
@@ -19,22 +20,21 @@ import static org.zwobble.mammoth.tests.documents.DocumentElementMakers.document
 import static org.zwobble.mammoth.tests.documents.DocumentElementMakers.paragraphWithText;
 import static org.zwobble.mammoth.tests.documents.DocumentElementMakers.withChildren;
 import static org.zwobble.mammoth.tests.docx.BodyXmlReaderMakers.bodyReader;
+import static org.zwobble.mammoth.tests.util.MammothAsserts.assertThrows;
 
 public class DocumentXmlTests {
-
     @Test
-    public void canReadTextWithinDocument() {
-        XmlElement documentElement = element("w:document", list(
-            element("w:body", list(
-                element("w:p", list(
-                    element("w:r", list(
-                        element("w:t", list(
-                            XmlNodes.text("Hello!")))))))))));
+    public void whenBodyElementIsPresentThenBodyIsRead() {
+        XmlElement textXml = element("w:t", list(XmlNodes.text("Hello!")));
+        XmlElement runXml = element("w:r", list(textXml));
+        XmlElement paragraphXml = element("w:p", list(runXml));
+        XmlElement bodyXml = element("w:body", list(paragraphXml));
+        XmlElement documentXml = element("w:document", list(bodyXml));
 
         DocumentXmlReader reader = new DocumentXmlReader(bodyReader(), Notes.EMPTY, list());
 
         assertThat(
-            reader.readElement(documentElement),
+            reader.readElement(documentXml),
             isInternalSuccess(document(
                 withChildren(paragraphWithText("Hello!"))
             ))
@@ -42,6 +42,25 @@ public class DocumentXmlTests {
     }
 
     @Test
+    public void whenBodyElementIsNotPresentThenErrorIsThrown() {
+        XmlElement paragraphXml = element("w:p");
+        XmlElement bodyXml = element("w:body2", list(paragraphXml));
+        XmlElement documentXml = element("w:document", list(bodyXml));
+
+        DocumentXmlReader reader = new DocumentXmlReader(bodyReader(), Notes.EMPTY, list());
+
+        IllegalArgumentException exception = assertThrows(
+            IllegalArgumentException.class,
+            () -> reader.readElement(documentXml)
+        );
+
+        assertThat(
+            exception.getMessage(),
+            equalTo("Could not find the body element: are you sure this is a docx file?")
+        );
+    }
+
+    @Test
     public void notesOfDocumentAreIncludedInDocument() {
         Note note = new Note(NoteType.FOOTNOTE, "4", list(paragraphWithText("Hello")));
         Notes notes = new Notes(list(note));