[cherry-pick] Get answer code from function instead of str. test=develop (#23904) (#23949)

python/paddle/fluid/tests/unittests/dygraph_to_static/test_program_translator.py

@@ -14,62 +14,79 @@
 
 from __future__ import print_function
 
+import astor
+import gast
+import inspect
+import textwrap
 import unittest
-import numpy as np
 
 import paddle.fluid as fluid
-
 from paddle.fluid.dygraph.dygraph_to_static import ProgramTranslator
 from paddle.fluid.dygraph.jit import dygraph_to_static_code
 
 from ifelse_simple_func import dyfunc_with_if_else
 
 
+def get_source_code(func):
+    raw_code = inspect.getsource(func)
+    code = textwrap.dedent(raw_code)
+    root = gast.parse(code)
+    source_code = astor.to_source(gast.gast_to_ast(root))
+    return source_code
+
+
+class StaticCode1():
+    def dyfunc_with_if_else(x_v, label=None):
+        def true_fn_0(x_v):
+            x_v = x_v - 1
+            return x_v
+
+        def false_fn_0(x_v):
+            x_v = x_v + 1
+            return x_v
+
+        x_v = fluid.layers.cond(
+            fluid.layers.mean(x_v)[0] > 5, lambda: true_fn_0(x_v),
+            lambda: false_fn_0(x_v))
+        if label is not None:
+            loss = fluid.layers.cross_entropy(x_v, label)
+            return loss
+        return x_v
+
+
+class StaticCode2():
+    def dyfunc_with_if_else(x_v, label=None):
+        def true_fn_1(x_v):
+            x_v = x_v - 1
+            return x_v
+
+        def false_fn_1(x_v):
+            x_v = x_v + 1
+            return x_v
+
+        x_v = fluid.layers.cond(
+            fluid.layers.mean(x_v)[0] > 5, lambda: true_fn_1(x_v),
+            lambda: false_fn_1(x_v))
+
+        if label is not None:
+            loss = fluid.layers.cross_entropy(x_v, label)
+            return loss
+        return x_v
+
+
 class TestDygraphToStaticCode(unittest.TestCase):
     def setUp(self):
         # set to print all string diff when assertEqual fails
         self.maxDiff = None
 
     def test_decorator(self):
-        answer = "\
-def dyfunc_with_if_else(x_v, label=None):\n\
-\n\
-    def true_fn_0(x_v):\n\
-        x_v = x_v - 1\n\
-        return x_v\n\
-\n\
-    def false_fn_0(x_v):\n\
-        x_v = x_v + 1\n\
-        return x_v\n\
-    x_v = fluid.layers.cond(fluid.layers.mean(x_v)[0] > 5, lambda :\n\
-        true_fn_0(x_v), lambda : false_fn_0(x_v))\n\
-    if label is not None:\n\
-        loss = fluid.layers.cross_entropy(x_v, label)\n\
-        return loss\n\
-    return x_v\n"
-
         x_v = None
+        answer = get_source_code(StaticCode1.dyfunc_with_if_else)
         code = dygraph_to_static_code(dyfunc_with_if_else)(x_v)
         self.assertEqual(answer, code)
 
     def test_program_translator(self):
-        answer = "\
-def dyfunc_with_if_else(x_v, label=None):\n\
-\n\
-    def true_fn_1(x_v):\n\
-        x_v = x_v - 1\n\
-        return x_v\n\
-\n\
-    def false_fn_1(x_v):\n\
-        x_v = x_v + 1\n\
-        return x_v\n\
-    x_v = fluid.layers.cond(fluid.layers.mean(x_v)[0] > 5, lambda :\n\
-        true_fn_1(x_v), lambda : false_fn_1(x_v))\n\
-    if label is not None:\n\
-        loss = fluid.layers.cross_entropy(x_v, label)\n\
-        return loss\n\
-    return x_v\n"
-
+        answer = get_source_code(StaticCode2.dyfunc_with_if_else)
         program_translator = ProgramTranslator()
         code = program_translator.get_code(dyfunc_with_if_else)
         self.assertEqual(answer, code)