Merge branch into development: View class now loads through Renderer

This branch contained some refactoring to move some of the View
class's loading logic into the Renderer class.  This will help
going forward as we change the Loader class.

pystache/renderer.py

@@ -6,9 +6,11 @@ This module provides a Renderer class to render templates.
 """
 
 import cgi
+import os
 import sys
 
 from .context import Context
+from .loader import DEFAULT_EXTENSION
 from .loader import Loader
 from .reader import Reader
 from .renderengine import RenderEngine
@@ -34,7 +36,8 @@ class Renderer(object):
     """
 
     def __init__(self, loader=None, file_encoding=None, default_encoding=None,
-                 decode_errors='strict', escape=None):
+                 decode_errors='strict', search_dirs=None, file_extension=None,
+                 escape=None):
         """
         Construct an instance.
 
@@ -49,7 +52,7 @@ class Renderer(object):
             the method should either return None (as dict.get() does) or
             raise an exception.
                 Defaults to constructing a default Loader, but using the
-            default_encoding and decode_errors arguments.
+            file_encoding and decode_errors arguments.
 
           escape: the function used to escape variable tag values when
             rendering a template.  The function should accept a unicode
@@ -80,28 +83,54 @@ class Renderer(object):
             strings of type str encountered during the rendering process.
             Defaults to "strict".
 
+          search_dirs: the list of directories in which to search for
+            templates when loading a template by name.  Defaults to the
+            current working directory.  If given a string, the string is
+            interpreted as a single directory.
+
+          file_extension: the template file extension.  Defaults to "mustache".
+            Pass False for no extension (i.e. for extensionless files).
+
         """
         if default_encoding is None:
             default_encoding = sys.getdefaultencoding()
 
-        if file_encoding is None:
-            file_encoding = default_encoding
-
         if escape is None:
             # The quote=True argument causes double quotes to be escaped,
             # but not single quotes:
             #   http://docs.python.org/library/cgi.html#cgi.escape
             escape = lambda s: cgi.escape(s, quote=True)
 
+        # This needs to be after we set the default default_encoding.
+        if file_encoding is None:
+            file_encoding = default_encoding
+
+        if file_extension is None:
+            file_extension = DEFAULT_EXTENSION
+
+        if search_dirs is None:
+            search_dirs = os.curdir  # i.e. "."
+
+        if isinstance(search_dirs, basestring):
+            search_dirs = [search_dirs]
+
+        # This needs to be after we set some of the defaults above.
         if loader is None:
-            reader = Reader(encoding=default_encoding, decode_errors=decode_errors)
-            loader = Loader(reader=reader)
+            reader = Reader(encoding=file_encoding, decode_errors=decode_errors)
+            loader = Loader(reader=reader, search_dirs=search_dirs, extension=file_extension)
 
         self.decode_errors = decode_errors
         self.default_encoding = default_encoding
         self.escape = escape
         self.file_encoding = file_encoding
+        self.file_extension = file_extension
+        # TODO: we should not store a loader attribute because the loader
+        # would no longer reflect the current attributes if, say, someone
+        # changed the search_dirs attribute after instantiation.  Instead,
+        # we should construct the Loader instance each time on the fly,
+        # as we do with the Reader in the read() method.
         self.loader = loader
+        self.search_dirs = search_dirs
 
     def _to_unicode_soft(self, s):
         """

pystache/view.py

@@ -23,6 +23,7 @@ class View(object):
     template_extension = None
 
     _loader = None
+    _renderer = None
 
     def __init__(self, template=None, context=None, loader=None, **kwargs):
         """
@@ -52,22 +53,20 @@ class View(object):
 
         self.context = _context
 
-    def get_loader(self):
-        if self._loader is None:
-            # We delay setting self._loader until now (in the case that the
-            # user did not supply a load_template to the constructor)
-            # to let users set the template_extension attribute, etc. after
-            # View.__init__() has already been called.
-            reader = Reader(encoding=self.template_encoding)
-            loader = Loader(search_dirs=self.template_path, reader=reader,
-                            extension=self.template_extension)
-            self._loader = loader
-
-        return self._loader
-
-    def load_template(self, template_name):
-        loader = self.get_loader()
-        return loader.get(template_name)
+    def _get_renderer(self):
+        if self._renderer is None:
+            # We delay setting self._renderer until now (instead of, say,
+            # setting it in the constructor) in case the user changes after
+            # instantiation some of the attributes on which the Renderer
+            # depends.  This lets users set the template_extension attribute,
+            # etc. after View.__init__() has already been called.
+            renderer = Renderer(loader=self._loader,
+                                file_encoding=self.template_encoding,
+                                search_dirs=self.template_path,
+                                file_extension=self.template_extension)
+            self._renderer = renderer
+
+        return self._renderer
 
     def get_template(self):
         """
@@ -76,7 +75,8 @@ class View(object):
         """
         if not self.template:
             template_name = self._get_template_name()
-            self.template = self.load_template(template_name)
+            renderer = self._get_renderer()
+            self.template = renderer.loader.get(template_name)
 
         return self.template
 
@@ -102,19 +102,13 @@ class View(object):
 
         return re.sub('[A-Z]', repl, template_name)[1:]
 
-    # TODO: the View class should probably have some sort of template renderer
-    # associated with it to encapsulate all of the render-specific behavior
-    # and options like encoding, escape, etc.  This would probably be better
-    # than passing all of these options to render(), especially as the list
-    # of possible options grows.
-    def render(self, escape=None):
+    def render(self):
         """
         Return the view rendered using the current context.
 
         """
-        loader = self.get_loader()
         template = self.get_template()
-        renderer = Renderer(escape=escape, loader=loader)
+        renderer = self._get_renderer()
         return renderer.render(template, self.context)
 
     def get(self, key, default=None):

tests/test_examples.py

@@ -31,10 +31,6 @@ class TestView(unittest.TestCase):
     def test_escaping(self):
         self.assertEquals(Escaped().render(), "<h1>Bear &gt; Shark</h1>")
 
-    def test_escaping__custom(self):
-        escape = lambda s: s.upper()
-        self.assertEquals(Escaped().render(escape=escape), "<h1>BEAR > SHARK</h1>")
-
     def test_literal(self):
         self.assertEquals(Unescaped().render(), "<h1>Bear > Shark</h1>")
 

tests/test_renderer.py

@@ -6,6 +6,7 @@ Unit tests of template.py.
 """
 
 import codecs
+import os
 import sys
 import unittest
 
@@ -46,12 +47,12 @@ class RendererInitTestCase(unittest.TestCase):
         self.assertEquals(actual.search_dirs, expected.search_dirs)
         self.assertEquals(actual.reader.__dict__, expected.reader.__dict__)
 
-    def test_loader__default__default_encoding(self):
+    def test_loader__default__encoding(self):
         """
-        Test that the default loader inherits default_encoding.
+        Test that the default loader inherits the correct encoding.
 
         """
-        renderer = Renderer(default_encoding='foo')
+        renderer = Renderer(file_encoding='foo')
         reader = renderer.loader.reader
 
         self.assertEquals(reader.encoding, 'foo')
@@ -66,6 +67,26 @@ class RendererInitTestCase(unittest.TestCase):
 
         self.assertEquals(reader.decode_errors, 'foo')
 
+    def test_loader__default__file_extension(self):
+        """
+        Test that the default loader inherits file_extension.
+
+        """
+        renderer = Renderer(file_extension='foo')
+        loader = renderer.loader
+
+        self.assertEquals(loader.template_extension, 'foo')
+
+    def test_loader__default__search_dirs(self):
+        """
+        Test that the default loader inherits search_dirs.
+
+        """
+        renderer = Renderer(search_dirs='foo')
+        loader = renderer.loader
+
+        self.assertEquals(loader.search_dirs, ['foo'])
+
     def test_escape__default(self):
         escape = Renderer().escape
 
@@ -113,7 +134,7 @@ class RendererInitTestCase(unittest.TestCase):
 
     def test_file_encoding__default(self):
         """
-        Check that file_encoding defaults to default_encoding.
+        Check the file_encoding default.
 
         """
         renderer = Renderer()
@@ -127,6 +148,46 @@ class RendererInitTestCase(unittest.TestCase):
         renderer = Renderer(file_encoding='foo')
         self.assertEquals(renderer.file_encoding, 'foo')
 
+    def test_file_extension__default(self):
+        """
+        Check the file_extension default.
+
+        """
+        renderer = Renderer()
+        self.assertEquals(renderer.file_extension, 'mustache')
+
+    def test_file_extension(self):
+        """
+        Check that the file_encoding attribute is set correctly.
+
+        """
+        renderer = Renderer(file_extension='foo')
+        self.assertEquals(renderer.file_extension, 'foo')
+
+    def test_search_dirs__default(self):
+        """
+        Check the search_dirs default.
+
+        """
+        renderer = Renderer()
+        self.assertEquals(renderer.search_dirs, [os.curdir])
+
+    def test_search_dirs__string(self):
+        """
+        Check that the search_dirs attribute is set correctly when a string.
+
+        """
+        renderer = Renderer(search_dirs='foo')
+        self.assertEquals(renderer.search_dirs, ['foo'])
+
+    def test_search_dirs__list(self):
+        """
+        Check that the search_dirs attribute is set correctly when a list.
+
+        """
+        renderer = Renderer(search_dirs=['foo'])
+        self.assertEquals(renderer.search_dirs, ['foo'])
+
 
 class RendererTestCase(unittest.TestCase):
 

tests/test_view.py

@@ -46,29 +46,16 @@ class ViewTestCase(unittest.TestCase):
         view = Simple(thing='world')
         self.assertEquals(view.render(), "Hi world!")
 
-    def test_load_template(self):
-        """
-        Test View.load_template().
-
-        """
-        template = Simple().load_template("escaped")
-        self.assertEquals(template, "<h1>{{title}}</h1>")
-
-    def test_load_template__extensionless_file(self):
-        view = Simple()
-        view.template_extension = False
-        template = view.load_template('extensionless')
-        self.assertEquals(template, "No file extension: {{foo}}")
-
     def test_load_template__custom_loader(self):
         """
         Test passing a custom loader to View.__init__().
 
         """
+        template = "{{>partial}}"
         partials = {"partial": "Loaded from dictionary"}
-        view = Simple(loader=partials)
+        view = Simple(template=template, loader=partials)
+        actual = view.render()
 
-        actual = view.load_template("partial")
         self.assertEquals(actual, "Loaded from dictionary")
 
     def test_template_path(self):