From 11f94cdce9dc00d6ea47b7e61871858443d15e89 Mon Sep 17 00:00:00 2001
From: liym27 <33742067+liym27@users.noreply.github.com>
Date: Tue, 24 Mar 2020 18:48:37 +0800
Subject: [PATCH] Improve function is_control_flow_to_transform. test=develop
 (#23109)

---
 python/paddle/fluid/dygraph/dygraph_to_static/utils.py      | 6 ++++--
 .../fluid/tests/unittests/dygraph_to_static/test_list.py    | 4 +++-
 2 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/python/paddle/fluid/dygraph/dygraph_to_static/utils.py b/python/paddle/fluid/dygraph/dygraph_to_static/utils.py
index c0ae00e801..581e727a5b 100644
--- a/python/paddle/fluid/dygraph/dygraph_to_static/utils.py
+++ b/python/paddle/fluid/dygraph/dygraph_to_static/utils.py
@@ -93,8 +93,10 @@ def is_control_flow_to_transform(node, var_name_to_type):
         "The type of input node must be gast.AST, but received %s." % type(node)
 
     if isinstance(node, gast.If):
-        # TODO: make a better condition
-        return True
+        from .ifelse_transformer import IfConditionVisitor
+        if_visitor = IfConditionVisitor(
+            node.test, node_var_type_map=var_name_to_type)
+        return if_visitor.is_control_flow()
 
     if isinstance(node, gast.For):
         # TODO: make a better condition
diff --git a/python/paddle/fluid/tests/unittests/dygraph_to_static/test_list.py b/python/paddle/fluid/tests/unittests/dygraph_to_static/test_list.py
index 129e7b3c56..b6461c9b2e 100644
--- a/python/paddle/fluid/tests/unittests/dygraph_to_static/test_list.py
+++ b/python/paddle/fluid/tests/unittests/dygraph_to_static/test_list.py
@@ -27,7 +27,9 @@ def test_list_without_control_flow(x):
     # Python list will not be transformed.
     x = fluid.dygraph.to_variable(x)
     a = []
-    a.append(x)
+    # It's a plain python control flow which won't be transformed
+    if 2 > 1:
+        a.append(x)
     return a
 
 
-- 
GitLab