Added example extension that uses the stream filtering and added unittests.

--HG--
branch : trunk

1 files changed, 78 insertions, 0 deletions

diff --git a/ext/inlinegettext.py b/ext/inlinegettext.py
new file mode 100644
index 0000000..049ab3b
--- /dev/null
+++ b/ext/inlinegettext.py
@@ -0,0 +1,78 @@
+# -*- coding: utf-8 -*-
+"""
+    Inline Gettext
+    ~~~~~~~~~~~~~~
+
+    An example extension for Jinja2 that supports inline gettext calls.
+    Requires the i18n extension to be loaded.
+
+    :copyright: Copyright 2008 by Armin Ronacher.
+    :license: BSD.
+"""
+import re
+from jinja2.ext import Extension
+from jinja2.lexer import Token, count_newlines
+from jinja2.exceptions import TemplateSyntaxError
+
+
+_outside_re = re.compile(r'\\?(gettext|_)\(')
+_inside_re = re.compile(r'\\?[()]')
+
+
+class InlineGettext(Extension):
+    """This extension implements support for inline gettext blocks::
+
+        <h1>_(Welcome)</h1>
+        <p>_(This is a paragraph)</p>
+
+    Requires the i18n extension to be loaded and configured.
+    """
+
+    def filter_stream(self, stream):
+        paren_stack = 0
+
+        for token in stream:
+            if token.type is not 'data':
+                yield token
+                continue
+
+            pos = 0
+            lineno = token.lineno
+
+            while 1:
+                if not paren_stack:
+                    match = _outside_re.search(token.value, pos)
+                else:
+                    match = _inside_re.search(token.value, pos)
+                if match is None:
+                    break
+                new_pos = match.start()
+                if new_pos > pos:
+                    preval = token.value[pos:new_pos]
+                    yield Token(lineno, 'data', preval)
+                    lineno += count_newlines(preval)
+                gtok = match.group()
+                if gtok[0] == '\\':
+                    yield Token(lineno, 'data', gtok[1:])
+                elif not paren_stack:
+                    yield Token(lineno, 'block_begin', None)
+                    yield Token(lineno, 'name', 'trans')
+                    yield Token(lineno, 'block_end', None)
+                    paren_stack = 1
+                else:
+                    if gtok == '(' or paren_stack > 1:
+                        yield Token(lineno, 'data', gtok)
+                    paren_stack += gtok == ')' and -1 or 1
+                    if not paren_stack:
+                        yield Token(lineno, 'block_begin', None)
+                        yield Token(lineno, 'name', 'endtrans')
+                        yield Token(lineno, 'block_end', None)
+                pos = match.end()
+
+            if pos < len(token.value):
+                yield Token(lineno, 'data', token.value[pos:])
+
+        if paren_stack:
+            raise TemplateSyntaxError('unclosed gettext expression',
+                                      token.lineno, stream.name,
+                                      stream.filename)