Add support for partials and path segments for Handlebars.

This introduces support for some missing features to the Handlebars lexer:
Partials and path segments. Partials mostly appeared to work before, but the
`>` in `{{> ... }}` would appear as a syntax error, as could other
components of the partial. This change introduces support for:

* Standard partials: `{{> partialName}}`
* Partials with parameters: `{{> partialName varname="value"}}`
* Ddynamic partials: `{{> (partialFunc)}}`
* Ddynamic partials with lookups: `{{> (lookup ../path "partialName")}}`
* Partial blocks: `{{> @partial-block}}`
* Inline partials: `{{#*inline}}..{{/inline}}`

It also introduces support for path segments, which can reference content in
the current context or in a parent context. For instance, `this.name`,
`this/name`, `./name`, `../name`, `this/name`, etc. These are all now tracked
as variables.

1 files changed, 94 insertions, 0 deletions

diff --git a/tests/test_inherit.py b/tests/test_inherit.py
new file mode 100644
index 00000000..34033a08
--- /dev/null
+++ b/tests/test_inherit.py
@@ -0,0 +1,94 @@
+# -*- coding: utf-8 -*-
+"""
+    Tests for inheritance in RegexLexer
+    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+    :copyright: Copyright 2006-2015 by the Pygments team, see AUTHORS.
+    :license: BSD, see LICENSE for details.
+"""
+
+import unittest
+
+from pygments.lexer import RegexLexer, inherit
+from pygments.token import Text
+
+
+class InheritTest(unittest.TestCase):
+    def test_single_inheritance_position(self):
+        t = Two()
+        pats = [x[0].__self__.pattern for x in t._tokens['root']]
+        self.assertEqual(['x', 'a', 'b', 'y'], pats)
+    def test_multi_inheritance_beginning(self):
+        t = Beginning()
+        pats = [x[0].__self__.pattern for x in t._tokens['root']]
+        self.assertEqual(['x', 'a', 'b', 'y', 'm'], pats)
+    def test_multi_inheritance_end(self):
+        t = End()
+        pats = [x[0].__self__.pattern for x in t._tokens['root']]
+        self.assertEqual(['m', 'x', 'a', 'b', 'y'], pats)
+
+    def test_multi_inheritance_position(self):
+        t = Three()
+        pats = [x[0].__self__.pattern for x in t._tokens['root']]
+        self.assertEqual(['i', 'x', 'a', 'b', 'y', 'j'], pats)
+
+    def test_single_inheritance_with_skip(self):
+        t = Skipped()
+        pats = [x[0].__self__.pattern for x in t._tokens['root']]
+        self.assertEqual(['x', 'a', 'b', 'y'], pats)
+
+
+class One(RegexLexer):
+    tokens = {
+        'root': [
+            ('a', Text),
+            ('b', Text),
+        ],
+    }
+
+class Two(One):
+    tokens = {
+        'root': [
+            ('x', Text),
+            inherit,
+            ('y', Text),
+        ],
+    }
+
+class Three(Two):
+    tokens = {
+        'root': [
+            ('i', Text),
+            inherit,
+            ('j', Text),
+        ],
+    }
+
+class Beginning(Two):
+    tokens = {
+        'root': [
+            inherit,
+            ('m', Text),
+        ],
+    }
+
+class End(Two):
+    tokens = {
+        'root': [
+            ('m', Text),
+            inherit,
+        ],
+    }
+
+class Empty(One):
+    tokens = {}
+
+class Skipped(Empty):
+    tokens = {
+        'root': [
+            ('x', Text),
+            inherit,
+            ('y', Text),
+        ],
+    }
+