From c48f0ca7e5dc070a2125673546b19614a7395d1b Mon Sep 17 00:00:00 2001
From: Jelte Fennema <github-tech@jeltef.nl>
Date: Thu, 27 Feb 2020 10:53:58 +0100
Subject: [PATCH] Make bad refactors to foreach_xxx error out

Without this commit you could still use varCell in the body of loop.
This makes it easy for bad refactors that still use the ListCell to slip
through unnoticed, because the new ListCell will be named the same as the
one used in the old code. By renaming the ListCell to varCellDoNotUse
this will not happen.
---
 src/include/distributed/listutils.h | 25 ++++++++++++++-----------
 1 file changed, 14 insertions(+), 11 deletions(-)

diff --git a/src/include/distributed/listutils.h b/src/include/distributed/listutils.h
index 891be1fe4..26819f00a 100644
--- a/src/include/distributed/listutils.h
+++ b/src/include/distributed/listutils.h
@@ -27,8 +27,8 @@
  *	  cell in.
  *
  *   How it works:
- *	  - A ListCell is declared with the name {var}Cell and used throughout the
- *	    for loop using ## to concat.
+ *	  - A ListCell is declared with the name {var}CellDoNotUse and used
+ *	    throughout the for loop using ## to concat.
  *	  - To assign to var it needs to be done in the condition of the for loop,
  *	    because we cannot use the initializer since a ListCell* variable is
  *	    declared there.
@@ -36,9 +36,10 @@
  *	    var is NULL.
  */
 #define foreach_ptr(var, l) \
-	for (ListCell *(var ## Cell) = list_head(l); \
-		 (var ## Cell) != NULL && (((var) = lfirst(var ## Cell)) || true); \
-		 var ## Cell = lnext(var ## Cell))
+	for (ListCell *(var ## CellDoNotUse) = list_head(l); \
+		 (var ## CellDoNotUse) != NULL && \
+		 (((var) = lfirst(var ## CellDoNotUse)) || true); \
+		 var ## CellDoNotUse = lnext(var ## CellDoNotUse))
 
 
 /*
@@ -48,9 +49,10 @@
  *	  For explanation of how it works see foreach_ptr.
  */
 #define foreach_int(var, l) \
-	for (ListCell *(var ## Cell) = list_head(l); \
-		 (var ## Cell) != NULL && (((var) = lfirst_int(var ## Cell)) || true); \
-		 var ## Cell = lnext(var ## Cell))
+	for (ListCell *(var ## CellDoNotUse) = list_head(l); \
+		 (var ## CellDoNotUse) != NULL && \
+		 (((var) = lfirst_int(var ## CellDoNotUse)) || true); \
+		 var ## CellDoNotUse = lnext(var ## CellDoNotUse))
 
 
 /*
@@ -60,9 +62,10 @@
  *	  For explanation of how it works see foreach_ptr.
  */
 #define foreach_oid(var, l) \
-	for (ListCell *(var ## Cell) = list_head(l); \
-		 (var ## Cell) != NULL && (((var) = lfirst_oid(var ## Cell)) || true); \
-		 var ## Cell = lnext(var ## Cell))
+	for (ListCell *(var ## CellDoNotUse) = list_head(l); \
+		 (var ## CellDoNotUse) != NULL && \
+		 (((var) = lfirst_oid(var ## CellDoNotUse)) || true); \
+		 var ## CellDoNotUse = lnext(var ## CellDoNotUse))
 
 
 /* utility functions declaration shared within this module */