refactor template inheritance

pandas-dev · jreback · May 26, 2021 · Sep 28, 2020 · Feb 24, 2021 · Feb 25, 2021
commit e1818f277da672640369eef0ba4680055e6ac558
diff --git a/pandas/io/formats/style.py b/pandas/io/formats/style.py
@@ -394,23 +39
8000
4,14 @@ def to_html(
             self.set_table_attributes(table_attributes)
 
         # Build HTML string..
-        styler_html = self.render(exclude_styles=exclude_styles).split("</style>\n")
-        if exclude_styles:
-            style, body = "", styler_html[0]
-        else:
-            style, body = "\n  " + styler_html[0] + "  </style>", styler_html[1]
-
-        if doctype_html:
-            html = (
-                f'<!DOCTYPE html>\n<html>\n<head>\n  <meta charset="'
-                f'{encoding if encoding is not None else "utf-8"}">'
-                f"{style}\n</head>\n<body>\n{body}</body>\n</html>\n"
-            )
-        else:
-            html = style + body
+        styler_html = self.render(
+            exclude_styles=exclude_styles,
+            encoding=encoding if encoding else "utf-8",
+            doctype_html=doctype_html,
+        )
 
         return save_to_buffer(
-            html, buf=buf, encoding=(encoding if buf is not None else None)
+            styler_html, buf=buf, encoding=(encoding if buf is not None else None)
         )
 
     def set_td_classes(self, classes: DataFrame) -> Styler:

diff --git a/pandas/io/formats/templates/html.tpl b/pandas/io/formats/templates/html.tpl
@@ -1,6 +1,20 @@
 {# Update the template_structure.html documentation too #}
+{% if doctype_html %}
+<!DOCTYPE html>
+<html>
+<head>
+<meta charset="{{encoding}}">
+{% if not exclude_styles %}{% include "html_style.tpl" %}{% endif %}
+</head>
+<body>
+{% if not exclude_styles %}{% include "html_body_inc.tpl" %}{% else %}{% include "html_body_exc.tpl" %}{% endif %}
+</body>
+</html>
+{% elif not doctype_html %}
 {% if exclude_styles %}
-{% extends "html_basic.tpl" %}
+{% include "html_body_exc.tpl" %}
 {% else %}
-{% extends "html_styles.tpl" %}
+{% include "html_style.tpl" %}
+{% include "html_body_inc.tpl" %}
+{% endif %}
 {% endif %}
diff --git a/pandas/io/formats/templates/html_basic.tpl → ...as/io/formats/templates/html_body_exc.tpl b/pandas/io/formats/templates/html_basic.tpl → ...as/io/formats/templates/html_body_exc.tpl
@@ -1,4 +1,3 @@
-{# this template excludes all style, ids and classes #}
 {% block before_table %}{% endblock before_table %}
 {% block table %}
 <table>

diff --git a/pandas/io/formats/templates/html_styles.tpl → ...as/io/formats/templates/html_body_inc.tpl b/pandas/io/formats/templates/html_styles.tpl → ...as/io/formats/templates/html_body_inc.tpl
@@ -1,28 +1,3 @@
-{# Update the template_structure.html document too #}
-{%- block before_style -%}{%- endblock before_style -%}
-{% block style %}
-<style type="text/css">
-{% block table_styles %}
-{% for s in table_styles %}
-#T_{{uuid}} {{s.selector}} {
-{% for p,val in s.props %}
-  {{p}}: {{val}};
-{% endfor %}
-}
-{% endfor %}
-{% endblock table_styles %}
-{% block before_cellstyle %}{% endblock before_cellstyle %}
-{% block cellstyle %}
-{% for s in cellstyle %}
-{% for selector in s.selectors %}{% if not loop.first %}, {% endif %}#T_{{uuid}}{{selector}}{% endfor %} {
-{% for p,val in s.props %}
-  {{p}}: {{val}};
-{% endfor %}
-}
-{% endfor %}
-{% endblock cellstyle %}
-</style>
-{% endblock style %}
 {% block before_table %}{% endblock before_table %}
 {% block table %}
 <table id="T_{{uuid}}"{% if table_attributes %} {{table_attributes}}{% endif %}>

diff --git a/pandas/io/formats/templates/html_style.tpl b/pandas/io/formats/templates/html_style.tpl
@@ -0,0 +1,24 @@
+{%- block before_style -%}{%- endblock before_style -%}
+{% block style %}
+<style type="text/css">
+{% block table_styles %}
+{% for s in table_styles %}
+#T_{{uuid}} {{s.selector}} {
+{% for p,val in s.props %}
+  {{p}}: {{val}};
+{% endfor %}
+}
+{% endfor %}
+{% endblock table_styles %}
+{% block before_cellstyle %}{% endblock before_cellstyle %}
+{% block cellstyle %}
+{% for s in cellstyle %}
+{% for selector in s.selectors %}{% if not loop.first %}, {% endif %}#T_{{uuid}}{{selector}}{% endfor %} {
+{% for p,val in s.props %}
+  {{p}}: {{val}};
+{% endfor %}
+}
+{% endfor %}
+{% endblock cellstyle %}
+</style>
+{% endblock style %}
diff --git a/pandas/tests/io/formats/style/test_html.py b/pandas/tests/io/formats/style/test_html.py
@@ -12,25 +12,28 @@
 
 
 @pytest.fixture
-def tpl_styles():
-    return env.get_template("html_styles.tpl")
+def tpl_style():
+    return env.get_template("html_style.tpl")
 
 
 @pytest.fixture
-def tpl_basic():
-    return env.get_template("html_basic.tpl")
+def tpl_body_exc():
+    return env.get_template("html_body_exc.tpl")
+
+
+@pytest.fixture
+def tpl_body_inc():
+    return env.get_template("html_body_inc.tpl")
 
 
 def test_html_template_extends_options():
     # make sure if templates are edited tests are updated as are setup fixtures
     # to understand the dependency
     with open("pandas/io/formats/templates/html.tpl") as file:
         result = file.read()
-    expected = (
-        '{% if exclude_styles %}\n{% extends "html_basic.tpl" %}\n'
-        '{% else %}\n{% extends "html_styles.tpl" %}\n'
-    )
-    assert expected in result
+    assert '{% include "html_body_exc.tpl" %}' in result
+    assert '{% include "html_style.tpl" %}' in result
+    assert '{% include "html_body_inc.tpl" %}' in result
 
 
 def test_exclude_styles():
@@ -41,7 +44,7 @@ def test_exclude_styles():
         <!DOCTYPE html>
         <html>
         <head>
-          <meta charset="utf-8">
+        <meta charset="utf-8">
         </head>
         <body>
         <table>
@@ -135,15 +138,19 @@ def test_rowspan_w3():
 
 def test_styles():
     s = Styler(DataFrame([[2.61], [2.69]], index=["a", "b"], columns=["A"]), uuid="abc")
+    s.set_table_styles([{"selector": "td", "props": "color: red;"}])
     result = s.to_html()
     expected = dedent(
         """\
         <!DOCTYPE html>
         <html>
         <head>
-          <meta charset="utf-8">
-          <style type="text/css">
-          </style>
+        <meta charset="utf-8">
+        <style type="text/css">
+        #T_abc_ td {
+          color: red;
+        }
+        </style>
         </head>
         <body>
         <table id="T_abc_">
@@ -171,14 +178,16 @@ def test_styles():
     assert result == expected
 
 
-def test_block_names(tpl_styles, tpl_basic):
+def test_block_names(tpl_style, tpl_body_inc, tpl_body_exc):
     # catch accidental removal of a block
-    expected1 = {
+    expected_style = {
         "before_style",
         "style",
         "table_styles",
         "before_cellstyle",
         "cellstyle",
+    }
+    expected_body = {
         "before_table",
         "table",
         "caption",
@@ -192,12 +201,14 @@ def test_block_names(tpl_styles, tpl_basic):
         "tr",
         "after_rows",
     }
-    result1 = set(tpl_styles.blocks)
-    assert result1 == expected1
+    result1 = set(tpl_style.blocks)
+    assert result1 == expected_style
+
+    result2 = set(tpl_body_exc.blocks)
+    assert result2 == expected_body
 
-    expected2 = {v for v in expected1 if "style" not in v}
-    result2 = set(tpl_basic.blocks)
-    assert result2 == expected2
+    result3 = set(tpl_body_inc.blocks)
+    assert result3 == expected_body
 
 
 def test_from_custom_template(tmpdir):