Add ignore_empty_paragraphs option

7 files changed, 36 insertions, 7 deletions

diff --git a/NEWS b/NEWS
index 6638eae..cb06b60 100644
--- a/NEWS
+++ b/NEWS
@@ -1,3 +1,7 @@
+# 0.3.14
+
+* Add ignore_empty_paragraphs option, which defaults to True.
+
 # 0.3.13
 
 * Always use forward slashes in ZIP paths. This should fix image handling on
diff --git a/README.md b/README.md
index 9d08a38..3e9fb8f 100644
--- a/README.md
+++ b/README.md
@@ -197,6 +197,9 @@ Converts the source document to HTML.
   
 * `convert_underline`: by default, the underlining of any text is ignored.
   Set this argument to [`mammoth.underline.element(name)`](#underline) to override the default behaviour.
+  
+* `ignore_empty_paragraphs`: by default, empty paragraphs are ignored.
+  Set this option to `False` to preserve empty paragraphs in the output.
 
 * Returns a result with the following properties:
 
diff --git a/mammoth/conversion.py b/mammoth/conversion.py
index e351395..1569849 100644
--- a/mammoth/conversion.py
+++ b/mammoth/conversion.py
@@ -14,7 +14,8 @@ def convert_document_element_to_html(element,
         convert_image=None,
         convert_underline=None,
         id_prefix=None,
-        output_format=None):
+        output_format=None,
+        ignore_empty_paragraphs=True):
             
     if style_map is None:
         style_map = []
@@ -26,17 +27,19 @@ def convert_document_element_to_html(element,
     converter = DocumentConverter(style_map,
         convert_image=convert_image,
         convert_underline=convert_underline,
-        id_prefix=id_prefix)
+        id_prefix=id_prefix,
+        ignore_empty_paragraphs=ignore_empty_paragraphs)
     converter.convert_element_to_html(element, html_generator,)
     html_generator.end_all()
     return results.Result(html_generator.as_string(), converter.messages)
 
 
 class DocumentConverter(object):
-    def __init__(self, style_map, convert_image, convert_underline, id_prefix):
+    def __init__(self, style_map, convert_image, convert_underline, id_prefix, ignore_empty_paragraphs):
         self.messages = []
         self._style_map = style_map
         self._id_prefix = id_prefix
+        self._ignore_empty_paragraphs = ignore_empty_paragraphs
         self._note_references = []
         self._converters = {
             documents.Document: self._convert_document,
@@ -76,6 +79,8 @@ class DocumentConverter(object):
     def _convert_paragraph(self, paragraph, html_generator):
         html_path = self._find_html_path_for_paragraph(paragraph)
         satisfy_html_path(html_generator, html_path)
+        if not self._ignore_empty_paragraphs:
+            html_generator.write_all()
         self._convert_elements_to_html(paragraph.children, html_generator)
 
 
diff --git a/mammoth/html_generation.py b/mammoth/html_generation.py
index a0c35b7..c7f4f38 100644
--- a/mammoth/html_generation.py
+++ b/mammoth/html_generation.py
@@ -9,14 +9,14 @@ class HtmlGenerator(object):
     
     def text(self, text):
         if text:
-            self._write_all()
+            self.write_all()
             self._writer.text(text)
     
     def start(self, name, attributes=None, always_write=False):
         self._stack.append(_Element(name, attributes))
         
         if always_write:
-            self._write_all()
+            self.write_all()
 
     def end(self):
         element = self._stack.pop()
@@ -30,7 +30,7 @@ class HtmlGenerator(object):
     def self_closing(self, name, attributes=None):
         self._writer.self_closing(name, attributes)
     
-    def _write_all(self):
+    def write_all(self):
         for element in self._stack:
             if not element.written:
                 element.written = True
@@ -42,7 +42,7 @@ class HtmlGenerator(object):
     def append(self, other):
         other_string = other.as_string()
         if other_string:
-            self._write_all()
+            self.write_all()
             self._writer.append(other_string)
     
     def as_string(self):
diff --git a/mammoth/options.py b/mammoth/options.py
index 3f47562..ad20d02 100644
--- a/mammoth/options.py
+++ b/mammoth/options.py
@@ -4,6 +4,7 @@ from . import style_reader, lists
 def read_options(options):
     custom_style_map = _read_style_map(options.get("style_map") or "")
     include_default_style_map = options.get("include_default_style_map", True)
+    options["ignore_empty_paragraphs"] = options.get("ignore_empty_paragraphs", True)
     
     options["style_map"] = custom_style_map + \
         (_default_style_map if include_default_style_map else [])
diff --git a/tests/mammoth_tests.py b/tests/mammoth_tests.py
index ce76221..d9f1093 100644
--- a/tests/mammoth_tests.py
+++ b/tests/mammoth_tests.py
@@ -26,6 +26,22 @@ def can_read_xml_files_with_utf8_bom():
 
 
 @istest
+def empty_paragraphs_are_ignored_by_default():
+    with open(test_path("empty.docx"), "rb") as fileobj:
+        result = mammoth.convert_to_html(fileobj=fileobj)
+        assert_equal("", result.value)
+        assert_equal([], result.messages)
+
+
+@istest
+def empty_paragraphs_are_preserved_if_ignore_empty_paragraphs_is_false():
+    with open(test_path("empty.docx"), "rb") as fileobj:
+        result = mammoth.convert_to_html(fileobj=fileobj, ignore_empty_paragraphs=False)
+        assert_equal("<p></p>", result.value)
+        assert_equal([], result.messages)
+
+
+@istest
 def inline_images_are_included_in_output():
     with open(test_path("tiny-picture.docx"), "rb") as fileobj:
         result = mammoth.convert_to_html(fileobj=fileobj)
diff --git a/tests/test-data/empty.docx b/tests/test-data/empty.docx
new file mode 100644
index 0000000..e10b869
--- /dev/null
+++ b/tests/test-data/empty.docx