Support $n tabstops for snipMate snippets.

Before, only ${n} tabstops were supported. Apparently snipMate changed
this behavior though, so now we support that too.

Fixes #533.

pythonx/UltiSnips/snippet/parsing/_base.py

@@ -7,6 +7,23 @@ from UltiSnips.position import Position
 from UltiSnips.snippet.parsing._lexer import tokenize, TabStopToken
 from UltiSnips.text_objects import TabStop
 
+from UltiSnips.text_objects import  Mirror
+from UltiSnips.snippet.parsing._lexer import MirrorToken
+
+
+def resolve_ambiguity(all_tokens, seen_ts):
+    """$1 could be a Mirror or a TabStop.
+
+    This figures this out.
+
+    """
+    for parent, token in all_tokens:
+        if isinstance(token, MirrorToken):
+            if token.number not in seen_ts:
+                seen_ts[token.number] = TabStop(parent, token)
+            else:
+                Mirror(parent, seen_ts[token.number], token)
+
 
 def tokenize_snippet_text(snippet_instance, text, indent,
                           allowed_tokens_in_text, allowed_tokens_in_tabstops,

pythonx/UltiSnips/snippet/parsing/snipmate.py

@@ -3,7 +3,7 @@
 
 """Parses a snipMate snippet definition and launches it into Vim."""
 
-from UltiSnips.snippet.parsing._base import tokenize_snippet_text, finalize
+from UltiSnips.snippet.parsing._base import tokenize_snippet_text, finalize, resolve_ambiguity
 from UltiSnips.snippet.parsing._lexer import EscapeCharToken, \
     VisualToken, TabStopToken, MirrorToken, ShellCodeToken
 from UltiSnips.text_objects import EscapedChar, Mirror, VimLCode, Visual
@@ -23,13 +23,6 @@ __ALLOWED_TOKENS_IN_TABSTOPS = [
 ]
 
 
-def _create_mirrors(all_tokens, seen_ts):
-    """Now that all tabstops are known, we can create mirrors."""
-    for parent, token in all_tokens:
-        if isinstance(token, MirrorToken):
-            Mirror(parent, seen_ts[token.number], token)
-
-
 def parse_and_instantiate(parent_to, text, indent):
     """Parses a snippet definition in snipMate format from 'text' assuming the
     current 'indent'.
@@ -41,5 +34,5 @@ def parse_and_instantiate(parent_to, text, indent):
     all_tokens, seen_ts = tokenize_snippet_text(parent_to, text, indent,
                                                 __ALLOWED_TOKENS, __ALLOWED_TOKENS_IN_TABSTOPS,
                                                 _TOKEN_TO_TEXTOBJECT)
-    _create_mirrors(all_tokens, seen_ts)
+    resolve_ambiguity(all_tokens, seen_ts)
     finalize(all_tokens, seen_ts, parent_to)

pythonx/UltiSnips/snippet/parsing/ultisnips.py

@@ -3,7 +3,7 @@
 
 """Parses a UltiSnips snippet definition and launches it into Vim."""
 
-from UltiSnips.snippet.parsing._base import tokenize_snippet_text, finalize
+from UltiSnips.snippet.parsing._base import tokenize_snippet_text, finalize, resolve_ambiguity
 from UltiSnips.snippet.parsing._lexer import EscapeCharToken, \
     VisualToken, TransformationToken, TabStopToken, MirrorToken, \
     PythonCodeToken, VimLCodeToken, ShellCodeToken
@@ -24,20 +24,6 @@ __ALLOWED_TOKENS = [
 ]
 
 
-def _resolve_ambiguity(all_tokens, seen_ts):
-    """$1 could be a Mirror or a TabStop.
-
-    This figures this out.
-
-    """
-    for parent, token in all_tokens:
-        if isinstance(token, MirrorToken):
-            if token.number not in seen_ts:
-                seen_ts[token.number] = TabStop(parent, token)
-            else:
-                Mirror(parent, seen_ts[token.number], token)
-
-
 def _create_transformations(all_tokens, seen_ts):
     """Create the objects that need to know about tabstops."""
     for parent, token in all_tokens:
@@ -59,6 +45,6 @@ def parse_and_instantiate(parent_to, text, indent):
     """
     all_tokens, seen_ts = tokenize_snippet_text(parent_to, text, indent,
                                                 __ALLOWED_TOKENS, __ALLOWED_TOKENS, _TOKEN_TO_TEXTOBJECT)
-    _resolve_ambiguity(all_tokens, seen_ts)
+    resolve_ambiguity(all_tokens, seen_ts)
     _create_transformations(all_tokens, seen_ts)
     finalize(all_tokens, seen_ts, parent_to)

test/test_SnipMate.py

@@ -87,6 +87,22 @@ snippet for
     wanted = 'for (j; j < blub; blub++) {\n\thi\n}'
 
 
+class snipMate_TestNoBraceTabstops(_VimTest):
+    files = { 'snippets/_.snippets': """
+snippet test
+\t$1 is $2"""}
+    keys = 'test' + EX + 'blub' + JF + 'blah'
+    wanted = 'blub is blah'
+
+
+class snipMate_TestNoBraceTabstopsAndMirrors(_VimTest):
+    files = { 'snippets/_.snippets': """
+snippet test
+\t$1 is $1, $2 is ${2}"""}
+    keys = 'test' + EX + 'blub' + JF + 'blah'
+    wanted = 'blub is blub, blah is blah'
+
+
 class snipMate_TestMirrorsInPlaceholders(_VimTest):
     files = { 'snippets/_.snippets': """
 snippet opt