Include embedded style map when explicit style map is set

5 files changed, 54 insertions, 10 deletions

diff --git a/NEWS b/NEWS
index 9105d08..fb917a0 100644
--- a/NEWS
+++ b/NEWS
@@ -1,3 +1,10 @@
+# 1.3.0
+
+* Add include_embedded_style_map argument to allow embedded style maps to be
+  disabled.
+
+* Include embedded styles when explicit style map is passed.
+
 # 1.2.2
 
 * Ignore bold, italic, underline and strikethrough elements that have a value of
diff --git a/README.md b/README.md
index 428cf8a..b0e83e5 100644
--- a/README.md
+++ b/README.md
@@ -270,6 +270,11 @@ Converts the source document to HTML.
 * `style_map`: a string to specify the mapping of Word styles to HTML.
   See the section "Writing style maps" for a description of the syntax.
 
+* `include_embedded_style_map`: by default,
+  if the document contains an embedded style, then it is combined with the default style map.
+  To ignore any embedded style maps,
+  pass `include_embedded_style_map=False`.
+
 * `include_default_style_map`: by default, the style map passed in `style_map` is combined with the default style map.
   To stop using the default style map altogether,
   pass `include_default_style_map=False`.
@@ -316,7 +321,7 @@ Each paragraph is followed by two newlines.
 
 Embeds the style map `style_map` into `fileobj`.
 When Mammoth reads a file object,
-it will use the embedded style if no explicit style map is provided.
+it will use the embedded style map.
 
 * `fileobj`: a file-like object containing the source document.
   Files should be opened for reading and writing in binary mode.
diff --git a/mammoth/__init__.py b/mammoth/__init__.py
index 7735fcf..fe480ec 100644
--- a/mammoth/__init__.py
+++ b/mammoth/__init__.py
@@ -5,6 +5,9 @@ from .docx.style_map import write_style_map, read_style_map
 __all__ = ["convert_to_html", "extract_raw_text", "images", "underline"]
 
 
+_undefined = object()
+
+
 def convert_to_html(*args, **kwargs):
     return convert(*args, output_format="html", **kwargs)
 
@@ -13,11 +16,13 @@ def convert_to_markdown(*args, **kwargs):
     return convert(*args, output_format="markdown", **kwargs)
 
 
-def convert(fileobj, transform_document=None, id_prefix=None, **kwargs):
+def convert(fileobj, transform_document=None, id_prefix=None, include_embedded_style_map=_undefined, **kwargs):
+    if include_embedded_style_map is _undefined:
+        include_embedded_style_map = True
     if transform_document is None:
         transform_document = lambda x: x
-    if kwargs.get("style_map") is None:
-        kwargs["style_map"] = read_style_map(fileobj)
+    if include_embedded_style_map:
+        kwargs["embedded_style_map"] = read_style_map(fileobj)
     return options.read_options(kwargs).bind(lambda convert_options:
         docx.read(fileobj).map(transform_document).bind(lambda document:
             conversion.convert_document_element_to_html(
diff --git a/mammoth/options.py b/mammoth/options.py
index ddac3de..d33b7ba 100644
--- a/mammoth/options.py
+++ b/mammoth/options.py
@@ -2,13 +2,24 @@ from . import style_reader, lists, results
 
 
 def read_options(options):
-    custom_style_map_result = _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)
+    custom_style_map_text = options.pop("style_map", "") or ""
+    embedded_style_map_text = options.pop("embedded_style_map", "") or ""
+    include_default_style_map = options.pop("include_default_style_map", True)
+    
+    read_style_map_result = results.combine([
+        _read_style_map(custom_style_map_text),
+        _read_style_map(embedded_style_map_text),
+    ])
+    
+    custom_style_map, embedded_style_map = read_style_map_result.value
+    style_map = custom_style_map + embedded_style_map
     
-    options["style_map"] = custom_style_map_result.value + \
-        (_default_style_map if include_default_style_map else [])
-    return custom_style_map_result.map(lambda _: options)
+    if include_default_style_map:
+        style_map += _default_style_map
+    
+    options["ignore_empty_paragraphs"] = options.get("ignore_empty_paragraphs", True)
+    options["style_map"] = style_map
+    return read_style_map_result.map(lambda _: options)
 
 
 def _read_style_map(style_text):
diff --git a/tests/mammoth_tests.py b/tests/mammoth_tests.py
index 4a524e8..322ebf7 100644
--- a/tests/mammoth_tests.py
+++ b/tests/mammoth_tests.py
@@ -64,6 +64,22 @@ def explicit_style_map_takes_precedence_over_embedded_style_map():
 
 
 @istest
+def explicit_style_map_is_combined_with_embedded_style_map():
+    with open(test_path("embedded-style-map.docx"), "rb") as fileobj:
+        result = mammoth.convert_to_html(fileobj=fileobj, style_map="r => strong")
+        assert_equal("<h1><strong>Walking on imported air</strong></h1>", result.value)
+        assert_equal([], result.messages)
+
+
+@istest
+def embedded_style_maps_can_be_disabled():
+    with open(test_path("embedded-style-map.docx"), "rb") as fileobj:
+        result = mammoth.convert_to_html(fileobj=fileobj, include_embedded_style_map=False)
+        assert_equal("<p>Walking on imported air</p>", result.value)
+        assert_equal([], result.messages)
+
+
+@istest
 def embedded_style_map_can_be_written_and_then_read():
     with _copy_of_test_data("single-paragraph.docx") as fileobj:
         mammoth.embed_style_map(fileobj, "p => h1")