[Dy2Stat] Fix error message when the message has more than one lines. (#30714)

python/paddle/fluid/dygraph/dygraph_to_static/error.py

@@ -143,9 +143,12 @@ class ErrorData(object):
             message_lines.append(traceback_frame.formated_message())
 
         # Step3: Adds error message like "TypeError: dtype must be int32, but received float32".
-        error_message = " " * 4 + traceback.format_exception_only(
-            self.error_type, self.error_value)[0].strip("\n")
-        message_lines.append(error_message)
+        # NOTE: `format_exception` is a list, its length is 1 in most cases, but sometimes its length
+        # is gather than 1, for example, the error_type is IndentationError.
+        format_exception = traceback.format_exception_only(self.error_type,
+                                                           self.error_value)
+        error_message = [" " * 4 + line for line in format_exception]
+        message_lines.extend(error_message)
 
         return '\n'.join(message_lines)
 

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

@@ -82,6 +82,22 @@ class LayerErrorInCompiletime(fluid.dygraph.Layer):
         return out
 
 
+class LayerErrorInCompiletime2(fluid.dygraph.Layer):
+    def __init__(self):
+        super(LayerErrorInCompiletime2, self).__init__()
+
+    @paddle.jit.to_static
+    def forward(self):
+        self.test_func()
+
+    def test_func(self):
+        """
+        NOTE: The next line has a tab. And this test to check the IndentationError when spaces and tabs are mixed.
+	A tab here.
+        """
+        return
+
+
 class TestFlags(unittest.TestCase):
     def setUp(self):
         self.reset_flags_to_default()
@@ -230,6 +246,32 @@ class TestErrorStaticLayerCallInCompiletime_2(
              ]
 
 
+class TestErrorStaticLayerCallInCompiletime_3(
+        TestErrorStaticLayerCallInCompiletime):
+    def setUp(self):
+        self.reset_flags_to_default()
+        self.set_func_call()
+        self.filepath = inspect.getfile(unwrap(self.func_call))
+        self.set_exception_type()
+        self.set_message()
+
+    def set_exception_type(self):
+        self.exception_type = IndentationError
+
+    def set_message(self):
+        self.expected_message = \
+            ['File "{}", line 91, in forward'.format(self.filepath),
+             'self.test_func()',
+             ]
+
+    def set_func_call(self):
+        layer = LayerErrorInCompiletime2()
+        self.func_call = lambda: layer()
+
+    def test_error(self):
+        self._test_raise_new_exception()
+
+
 class TestErrorStaticLayerCallInRuntime(TestErrorStaticLayerCallInCompiletime):
     def set_func(self):
         self.func = func_error_in_runtime