unwarper: Fix slot elimination stack overflow on a cycled AST

Prashant-Jonny · Jan 25, 2014 · 062c6a3 · 062c6a3
1 parent 33e2876
commit 062c6a3
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Showing 2 changed files with 8 additions and 2 deletions.
diff --git a/ljd/ast/unwarper.py b/ljd/ast/unwarper.py
@@ -219,15 +219,19 @@ def _unwarp_expressions_pack(blocks, pack):
 			replacements[start] = end
 
 			slotworks.eliminate_temporary(end)
+
+			_set_flow_to(start, end)
 		else:
 			blocks = blocks[:start_index + 1] + blocks[end_index:]
 
 			start.contents = statements[:split_i]
 			end.contents = statements[split_i:]
 
-			slotworks.eliminate_temporary(start)
+			# We need to kill the start's warp before slot
+			# elimination or it could result in a cycled AST.
+			_set_flow_to(start, end)
 
-		_set_flow_to(start, end)
+			slotworks.eliminate_temporary(start)
 
 	return blocks
 

diff --git a/test/expression.lua b/test/expression.lua
@@ -253,5 +253,7 @@ local function foo()
 	}
 end
 
+menu.logbook = foo(x or y) or {}
+
 --[[
 --]]
-Original file line number
+Diff line change
@@ Expand Up / @@ -253,5 +253,7 @@ local function foo() @@
     	}
     end
+    menu.logbook = foo(x or y) or {}
     --[[
     --]]