use a utility function to get the name of a stack from the blocks

2 files changed, 32 insertions, 11 deletions

diff --git a/TurtleArt/talogo.py b/TurtleArt/talogo.py
index b96a2b9..fb78bf7 100644
--- a/TurtleArt/talogo.py
+++ b/TurtleArt/talogo.py
@@ -39,7 +39,8 @@ from tablock import (Block, media_blocks_dictionary)
 from taconstants import (TAB_LAYER, DEFAULT_SCALE)
 from tapalette import (block_names, value_blocks)
 from tautils import (get_pixbuf_from_journal, convert, data_from_file,
-                     text_media_type, round_int, debug_output, find_group)
+                     text_media_type, round_int, debug_output, find_group,
+                     get_stack_name)
 
 try:
     from util.RtfParser import RtfTextOnly
@@ -248,17 +249,17 @@ class LogoCode:
                 code = self._blocks_to_code(b)
                 self.stacks['stack2'] = self._readline(code)
             elif b.name == 'hat':
-                if b.connections is not None and len(b.connections) > 1 and \
-                   b.connections[1] is not None:
+                stack_name = get_stack_name(b)
+                if (b.connections is not None and len(b.connections) > 1 and
+                        stack_name):
                     code = self._blocks_to_code(b)
-                    try:
-                        x = b.connections[1].values[0]
-                    except IndexError:
-                        self.tw.showlabel('#nostack')
-                        self.tw.showblocks()
-                        self.tw.running_blocks = False
-                        return None
-                    self.stacks[self._get_stack_key(x)] = self._readline(code)
+                    stack_key = self._get_stack_key(stack_name)
+                    self.stacks[stack_key] = self._readline(code)
+                else:
+                    self.tw.showlabel('#nostack')
+                    self.tw.showblocks()
+                    self.tw.running_blocks = False
+                    return None
 
         code = self._blocks_to_code(blk)
 
diff --git a/TurtleArt/tautils.py b/TurtleArt/tautils.py
index 244be6d..a8ef384 100644
--- a/TurtleArt/tautils.py
+++ b/TurtleArt/tautils.py
@@ -808,6 +808,26 @@ def find_blk_below(blk, namelist):
     return None
 
 
+def get_stack_name(blk):
+    ''' Return the name of the action stack that the given block belongs to.
+    If the top block of this stack is not a stack-defining block, return
+    None. '''
+    top_block = find_top_block(blk)
+    if top_block.name == 'start':
+        return 'start'
+    elif top_block.name == 'hat1':
+        return 'stack1'
+    elif top_block.name == 'hat2':
+        return 'stack2'
+    elif top_block.name == 'hat':
+        try:
+            return top_block.connections[1].values[0]
+        except (IndexError, AttributeError):
+            return None
+    else:
+        return None
+
+
 def get_hardware():
     ''' Determine whether we are using XO 1.0, 1.5, ... or 'unknown'
     hardware '''