Add strict fonts rule (#53)

Author: soffes

README.md

@@ -56,13 +56,17 @@ in the .xib or .storyboard file.
 
   Ensures there are no links to other storyboards in different bundles.
 
+- `strict_fonts`
+
+  Ensures all font names and sizes are in an allowed set. Configure `allowed_fonts` with an array of dictionaries containing a `name` and `size` in a custom rule configuration using `rules_config` (see below).
+
 - `strict_font_names`
 
-  Ensures all fonts are in an allowed set. Configure `allowed_fonts` and `allow_system_fonts` (default is `true`) in a custom rule configuration using `rules_config` (see below).
+  Ensures all font namess are in an allowed set. Configure `allowed_fonts` and `allow_system_fonts` (default is `true`) in a custom rule configuration using `rules_config` (see below). This is a good option if `strict_fonts` is too strict.
 
 - `strict_font_sizes`
 
-  Ensures all fonts are above a minimum font size. Configure `minimum_size` (default is `0`) and/or `maximum_size` (default is `1000`) in a custom rule configuration using `rules_config` (see below).
+  Ensures all font sizes are above a minimum font size. Configure `minimum_size` (default is `0`) and/or `maximum_size` (default is `1000`) in a custom rule configuration using `rules_config` (see below). This is a good option if `strict_fonts` is too strict.
 
 - `unavailable_custom_classes`
 

xiblint/__init__.py

@@ -1 +1 @@
-__version__ = '0.9.11'
+__version__ = '0.9.12'

xiblint/rules/strict_fonts.py

@@ -0,0 +1,53 @@
+from xiblint.rules import Rule
+from xiblint.xibcontext import XibContext
+
+
+class StrictFonts(Rule):
+    """
+    Ensures font name and size combinations are in the allowed set. This would generally be used instead
+    of strict_font_names and strict_font_sizes.
+
+    Example configuration:
+    {
+      "allowed_fonts": [
+        {
+          "name": "ComicSans-Regular",
+          "size": 14
+        },
+        {
+          "name": "ComicSans-Bold",
+          "size": 14
+        }
+      ]
+    }
+    """
+    def check(self, context):  # type: (XibContext) -> None
+        allowed_fonts = [(d["name"], d["size"]) for d in self.config.get('allowed_fonts', [])]
+
+        for element in context.tree.findall('.//font') + context.tree.findall('.//fontDescription'):
+            size_attribute_name = None
+
+            if element.tag == 'font':
+                # Skip <font> tags nested in a localization comment
+                container = element.parent.parent.parent
+                if container.tag == 'attributedString' and container.get('key') == 'userComments':
+                    continue
+
+                size_attribute_name = 'size'
+            else:
+                size_attribute_name = 'pointSize'
+
+            raw_size = element.get(size_attribute_name)
+            if raw_size is None:
+                context.error(element, 'Invalid <{}> found. Must have a {}.'.format(element.tag, size_attribute_name))
+                continue
+
+            size = int(raw_size)
+
+            name = element.get('name')
+            if name is None:
+                context.error(element, 'Invalid <{}> found. Must have a name.'.format(element.tag))
+                continue
+
+            if (name, size) not in allowed_fonts:
+                context.error(element, 'Invalid font found {} {}. Please use an allowed font.'.format(name, size))