Fixed incorrect information on Python frames in MuranoPL stack traces

Python frames in mixed stack traces were missing file name and pointed to a line
below correct position

Change-Id: I335292f40b3b6ea3dbca80b84f1d8dbed9a6581d
Fixes: bug #1331113

murano/common/engine.py

@@ -123,7 +123,7 @@ class TaskExecutor(object):
                     self._invoke(exc)
             except Exception as e:
                 if isinstance(e, dsl_exception.MuranoPlException):
-                    LOG.error(e.format())
+                    LOG.error('\n' + e.format(prefix='  '))
                 else:
                     LOG.exception(e)
                 reporter = status_reporter.StatusReporter()

murano/dsl/dsl_exception.py

@@ -71,8 +71,8 @@ class MuranoPlException(Exception):
         else:
             return self._names
 
-    def format(self, prefix='  '):
-        text = '\n{3}{0}: {1}\n' \
+    def format(self, prefix=''):
+        text = '{3}{0}: {1}\n' \
                '{3}Traceback (most recent call last):\n' \
                '{2}'.format(self._format_name(), self.message,
                             self.stacktrace.toString(prefix + '  '), prefix)

murano/dsl/principal_objects/stack_trace.py

@@ -45,25 +45,15 @@ class StackTrace(murano_object.MuranoObject):
         frames.reverse()
 
         if includeNativeFrames:
-            class InstructionStub(object):
-                def __init__(self, title, position):
-                    self._title = title
-                    self.source_file_position = position
-
-                def __str__(self):
-                    return self._title
-
             native_frames = []
             for frame in inspect.trace()[1:]:
-                info = inspect.getframeinfo(frame[0])
-                position = yaql_expression.YaqlExpressionFilePosition(
-                    os.path.abspath(info.filename), info.lineno,
+                location = yaql_expression.YaqlExpressionFilePosition(
+                    os.path.abspath(frame[1]), frame[2],
                     -1, -1, -1, -1, -1)
-                instruction = InstructionStub(
-                    info.code_context[0].strip(), position)
-                method = info.function
+                method = frame[3]
                 native_frames.append({
-                    'instruction': instruction,
+                    'instruction': frame[4][0].strip(),
+                    'location': location,
                     'method': method,
                     'class': None
                 })
@@ -77,6 +67,8 @@ class StackTrace(murano_object.MuranoObject):
             method = frame['method']
             murano_class = frame['class']
             location = frame['location']
+            if murano_class:
+                method += ' of class ' + murano_class.name
 
             if location:
                 args = (
@@ -86,14 +78,12 @@ class StackTrace(murano_object.MuranoObject):
                     if location.start_column >= 0 else '',
                     method,
                     instruction,
-                    prefix,
-                    '' if not murano_class else murano_class.name + '::'
+                    prefix
                 )
-                return '{5}File "{0}", line {1}{2} in method {6}{3}\n' \
+                return '{5}File "{0}", line {1}{2} in method {3}\n' \
                        '{5}    {4}'.format(*args)
             else:
-                return '{2}File <unknown> in method {3}{0}\n{2}    {1}'.format(
-                    method, instruction, prefix,
-                    '' if not murano_class else murano_class.name + '::')
+                return '{2}File <unknown> in method {0}\n{2}    {1}'.format(
+                    method, instruction, prefix)
 
         return '\n'.join([format_frame(t)for t in self.get_property('frames')])

murano/tests/dsl/meta/ExceptionHandling.yaml

@@ -49,3 +49,7 @@ Methods:
             - Return:
         Value: $enum
 
+  testStackTrace:
+    Body:
+      raisePythonException()
+

murano/tests/dsl/test_exceptions.py

@@ -12,6 +12,12 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
+import inspect
+import os.path
+import re
+
+from testtools import matchers
+
 from murano.dsl import dsl_exception
 from murano.tests.dsl.foundation import object_model as om
 from murano.tests.dsl.foundation import test_case
@@ -20,6 +26,16 @@ from murano.tests.dsl.foundation import test_case
 class TestExceptions(test_case.DslTestCase):
     def setUp(self):
         super(TestExceptions, self).setUp()
+
+        def exception_func():
+            exc = LookupError('just random Python exception')
+            frameinfo = inspect.getframeinfo(inspect.currentframe())
+            exc._position = \
+                os.path.basename(frameinfo.filename), frameinfo.lineno + 4
+            # line below must be exactly 4 lines after currentframe()
+            raise exc
+
+        self.register_function(exception_func, 'raisePythonException')
         self._runner = self.new_runner(om.Object('ExceptionHandling'))
 
     def test_throw_catch(self):
@@ -54,3 +70,27 @@ class TestExceptions(test_case.DslTestCase):
         self.assertEqual(
             ['enter try', 'exit try', 'else section', 'finally section'],
             self.traces)
+
+    def test_stack_trace(self):
+        self._runner.preserve_exception = True
+        e = self.assertRaises(
+            dsl_exception.MuranoPlException,
+            self._runner.testStackTrace)
+        call_stack = e.format()
+        self.assertThat(
+            call_stack,
+            matchers.StartsWith(
+                'exceptions.LookupError: just random Python exception'))
+
+        self.assertIsInstance(e.original_exception, LookupError)
+
+        filename, line = e.original_exception._position
+        self.assertThat(
+            call_stack,
+            matchers.MatchesRegex(
+                r'.*^  File \".*ExceptionHandling\.yaml\", '
+                r'line \d+:\d+ in method testStackTrace .*'
+                r'of class ExceptionHandling$.*'
+                r'^  File \".*{0}\", line {1} '
+                r'in method exception_func$.*'.format(filename, line),
+                re.MULTILINE | re.DOTALL))