doc: add DocumentPart.get_style()

Steve Canny · Steve Canny · commit c0ea3330dc50 · 2015-02-08T00:01:14.000-08:00
diff --git a/docx/parts/document.py b/docx/parts/document.py
@@ -72,7 +72,7 @@ def get_style(self, style_id, style_type):
         default style for *style_type* if *style_id* is |None| or does not
         match a defined style of *style_type*.
         """
-        raise NotImplementedError
+        return self.styles.get_by_id(style_id, style_type)
 
     @lazyproperty
     def inline_shapes(self):
diff --git a/docx/styles/styles.py b/docx/styles/styles.py
@@ -38,6 +38,14 @@ def __iter__(self):
     def __len__(self):
         return len(self._element.style_lst)
 
+    def get_by_id(self, style_id, style_type):
+        """
+        Return the style of *style_type* matching *style_id*. Returns the
+        default for *style_type* if *style_id* is not found or is |None|, or
+        if the style having *style_id* is not of *style_type*.
+        """
+        raise NotImplementedError
+
     @staticmethod
     def _translate_special_case_names(name):
         """
diff --git a/tests/parts/test_document.py b/tests/parts/test_document.py
@@ -18,6 +18,7 @@
 from docx.parts.styles import StylesPart
 from docx.section import Section
 from docx.shape import InlineShape
+from docx.styles.style import BaseStyle
 from docx.styles.styles import Styles
 from docx.table import Table
 from docx.text.paragraph import Paragraph
@@ -105,6 +106,14 @@ def it_knows_the_next_available_xml_id(self, next_id_fixture):
         document, expected_id = next_id_fixture
         assert document.next_id == expected_id
 
+    def it_can_get_a_style_by_id(self, get_style_fixture):
+        document_part, style_id, style_type, style_ = get_style_fixture
+        style = document_part.get_style(style_id, style_type)
+        document_part.styles.get_by_id.assert_called_once_with(
+            style_id, style_type
+        )
+        assert style is style_
+
     def it_provides_access_to_its_styles_part_to_help(
             self, styles_part_get_fixture):
         document_part, styles_part_ = styles_part_get_fixture
@@ -146,7 +155,7 @@ def add_table_fixture(self, document_part_body_, body_, table_):
         return document_part, rows, cols, body_, table_
 
     @pytest.fixture
-    def body_fixture(self, request, _Body_):
+    def body_fixture(self, _Body_):
         document_elm = (
             a_document().with_nsdecls().with_child(
                 a_body())
@@ -155,6 +164,13 @@ def body_fixture(self, request, _Body_):
         document_part = DocumentPart(None, None, document_elm, None)
         return document_part, _Body_, body_elm
 
+    @pytest.fixture
+    def get_style_fixture(self, styles_prop_, style_):
+        document_part = DocumentPart(None, None, None, None)
+        style_id, style_type = 'Foobar', 1
+        styles_prop_.return_value.get_by_id.return_value = style_
+        return document_part, style_id, style_type, style_
+
     @pytest.fixture
     def inline_shapes_fixture(self, request, InlineShapes_):
         document_elm = (
@@ -325,6 +341,10 @@ def sectPr_(self, request):
     def start_type_(self, request):
         return instance_mock(request, int)
 
+    @pytest.fixture
+    def style_(self, request):
+        return instance_mock(request, BaseStyle)
+
     @pytest.fixture
     def styles_(self, request):
         return instance_mock(request, Styles)
@@ -337,6 +357,12 @@ def StylesPart_(self, request):
     def styles_part_(self, request):
         return instance_mock(request, StylesPart)
 
+    @pytest.fixture
+    def styles_prop_(self, request, styles_):
+        return property_mock(
+            request, DocumentPart, 'styles', return_value=styles_
+        )
+
     @pytest.fixture
     def _styles_part_prop_(self, request):
         return property_mock(request, DocumentPart, '_styles_part')
