adding more powerful support for single-statement control structures to support scala's lack of semicolons

--HG--
branch : pmacs2

mode/scala.py

@@ -64,7 +64,21 @@ class ScalaTabber(StackTabber2):
     is_ignored_tokens  = set(('spaces', 'eol', 'comment', 'comment.start',
                               'comment.data', 'comment.null', 'comment.end'))
     is_indent_tokens   = set(('spaces',))
-    def is_base(self, y): return y == 0
+    def _is_base(self, y):
+        # the first line is always safe
+        if y == 0: return True
+
+        # if there are no tokens we don't really have any info
+        tokens = self._get_tokens(y)
+        if not tokens: return False
+
+        # if it looks like a top-level class, object or function, then say ok
+        t = tokens[0]
+        if t.fqmatchs('scala.reserved', ('class', 'object', 'def')):
+            return True
+
+        # the default is to assume no
+        return False
 
 class Scala(Fundamental):
     name        = 'Scala'

tab.py

@@ -247,6 +247,8 @@ class StackTabber2(Tabber):
     close_tokens       = {'delimiter': set(['}', ')', ']'])}
     open_scope_tokens  = {'delimiter': set(['{'])}
     close_scope_tokens = {'delimiter': set(['}'])}
+    open_test_tokens   = {'delimiter': set(['('])}
+    close_test_tokens  = {'delimiter': set([')'])}
     control_tokens     = {'keyword': set(['if', 'else', 'while', 'do', 'for'])}
     end_at_eof         = True
     end_at_tokens      = {}
@@ -383,6 +385,17 @@ class StackTabber2(Tabber):
         if i == 0:
             self._save_curr_level()
 
+        # if we need to end at eof and we're at the EOF and we have a control
+        # token, then we need to pop it.
+        if self.end_at_eof and i == end - start and self._match('control'):
+            self.stack.pop()
+
+        # if we are in a control test and this closes the test, then we need to
+        # mark that we're out of the control test.
+        if self._match('in-control') and \
+            t.string in self.close_test_tokens.get(t.name, set()):
+            self.stack[-1].name = 'control'
+
         # if we don't want implicit continuation, return.
         if self.end_at_eof:
             return
@@ -408,9 +421,18 @@ class StackTabber2(Tabber):
 
     def _is_open_token(self, t):
         return t.string in self.open_tokens.get(t.name, set())
+
     def _handle_open_token(self, y, tokens, start, end, i, t):
-        if i == 0 and self.stack and self.stack[-1].name == 'continue':
+        if self.stack:
+            if i == 0 and self._match('continue'):
                 self.stack.pop()
+
+            # if we have seen a control token, and we are starting a test, then
+            # need to note that we've entered the test stanza.
+            if self._match('pre-control') and \
+                t.string in self.open_test_tokens.get(t.name, set()):
+                self.stack[-1].name = 'in-control'
+
         if t.string in self.open_scope_tokens.get(t.name, set()):
             self._pop('continue', 'control')
         if i == 0 and t.string in self.open_scope_tokens.get(t.name, set()):
@@ -472,4 +494,5 @@ class StackTabber2(Tabber):
             if i == start:
                 self._save_curr_level()
             self._pop_while('continue');
-            self._append_unless('control', name, self._get_next_level(), y)
+            #self._append_unless('control', name, self._get_next_level(), y)
+            self._append_unless('pre-control', name, self._get_next_level(), y)