Adding template Loader class

pystache/__init__.py

@@ -1,5 +1,6 @@
 from pystache.template import Template
 from pystache.view import View
+from pystache.loader import Loader
 
 def render(template, context=None, **kwargs):
     context = context and context.copy() or {}

pystache/loader.py

@@ -0,0 +1,41 @@
+import os
+
+class Loader(object):
+    
+    template_extension = 'mustache'
+    template_path = '.'
+    template_encoding = None
+    
+    def load_template(self, template_name, template_dirs=None):
+        '''Returns the template string from a file or throws IOError if it non existent'''
+        if None == template_dirs:
+            template_dirs = self.template_path
+    
+        file_name = template_name + '.' + self.template_extension
+
+        # Given a single directory we'll load from it
+        if isinstance(template_dirs, basestring):
+            file_path = os.path.join(template_dirs, file_name)
+
+            return self._load_template_file(file_path)
+            
+        # Given a list of directories we'll check each for our file
+        for path in template_dirs:
+            file_path = os.path.join(path, file_name)
+            if os.path.exists(file_path):
+                return self._load_template_file(file_path)
+                
+        raise IOError('"%s" not found in "%s"' % (template_name, ':'.join(template_dirs),))
+    
+    def _load_template_file(self, file_path):
+        '''Loads and returns the template file from disk'''
+        f = open(file_path, 'r')
+        
+        try:
+            template = f.read()
+            if self.template_encoding:
+                template = unicode(template, self.template_encoding)
+        finally:
+            f.close()
+        
+        return template

pystache/template.py

@@ -1,6 +1,7 @@
 import re
 import cgi
 import collections
+import os
 
 modifiers = {}
 def modifier(symbol):
@@ -107,6 +108,7 @@ class Template(object):
         insides = []
         for item in listing:
             view = View(context=item)
+            view.template_path = self.view.template_path
             view.parent = self.view
             insides.append(Template(template, view).render())
             
@@ -117,6 +119,12 @@ class Template(object):
         raw = view.get(tag_name, '')
         
         return cgi.escape(unicode(raw))
+    
+    @modifier('>')
+    def _render_partial(self, template_name, view):
+        # mothereffin template loader goes here
+        template = view.get_template(template_name)
+        return Template(template, view).render()
 
     def render(self):
         template = self._render_sections(self.template, self.view)

pystache/view.py

@@ -5,6 +5,10 @@ from types import *
 
 class View(object):
     
+    template_name = None
+    template_path = None
+    template = None
+    
     def __init__(self, template=None, context=None, **kwargs):
         self.template = template
         self.context = context or {}
@@ -22,4 +26,31 @@ class View(object):
         if hasattr(self, 'parent'):
             return self.parent.get(attr, default)
         else:
-            return default
+            return default
+    
+    def get_template(self, template_name):
+        if not self.template:
+            from pystache import Loader
+            template_name = self._get_template_name(template_name)
+            self.template = Loader().load_template(template_name, self.template_path)
+        
+        return self.template
+
+    def _get_template_name(self, template_name=None):
+        """TemplatePartial => template_partial
+        Takes a string but defaults to using the current class' name or
+        the `template_name` attribute
+        """
+        if self.template_name:
+            return self.template_name
+
+        if not template_name:
+            template_name = self.__class__.__name__
+
+        def repl(match):
+            return '_' + match.group(0).lower()
+
+        return re.sub('[A-Z]', repl, template_name)[1:]
+
+    def render(self):        
+        return Template(self.get_template(self.template_name), self).render()

tests/test_loader.py

@@ -0,0 +1,21 @@
+import unittest
+import pystache
+
+class TestLoader(unittest.TestCase):
+    
+    def test_template_is_loaded(self):
+        loader = pystache.Loader()
+        template = loader.load_template('simple', 'examples')
+        
+        self.assertEqual(template, 'Hi {{thing}}!{{blank}}')
+        
+    def test_using_list_of_paths(self):
+        loader = pystache.Loader()
+        template = loader.load_template('simple', ['doesnt_exist', 'examples'])
+        
+        self.assertEqual(template, 'Hi {{thing}}!{{blank}}')
+        
+    def test_non_existent_template_fails(self):
+        loader = pystache.Loader()
+        
+        self.assertRaises(IOError, loader.load_template, 'simple', 'doesnt_exist')

tests/test_simple.py

@@ -3,13 +3,12 @@ import pystache
 from examples.nested_context import NestedContext
 from examples.complex_view import ComplexView
 from examples.lambdas import Lambdas
+from examples.template_partial import TemplatePartial
 
 class TestSimple(unittest.TestCase):
     
     def test_simple_render(self):
-        tmpl = '{{derp}}'
-        
-        self.assertEqual('herp', pystache.Template(tmpl, {'derp': 'herp'}).render())
+        self.assertEqual('herp', pystache.Template('{{derp}}', {'derp': 'herp'}).render())
         
     def test_nested_context(self):
         view = NestedContext()
@@ -25,4 +24,10 @@ class TestSimple(unittest.TestCase):
         
     def test_callables(self):
         view = Lambdas()
-        self.assertEquals(pystache.Template('{{#replace_foo_with_bar}}foo != bar. oh, it does!{{/replace_foo_with_bar}}', view).render(), 'bar != bar. oh, it does!')
+        self.assertEquals(pystache.Template('{{#replace_foo_with_bar}}foo != bar. oh, it does!{{/replace_foo_with_bar}}', view).render(), 'bar != bar. oh, it does!')
+        
+    def test_rendering_partial(self):
+        view = TemplatePartial()
+        self.assertEquals(pystache.Template('{{>inner_partial}}', view).render(), 'Again, Welcome!')
+        
+        self.assertEquals(pystache.Template('{{#looping}}{{>inner_partial}} {{/looping}}', view).render(), 'Again, Welcome! Again, Welcome! Again, Welcome! ')