Fix looping over string of space-separated words

devassistant/yaml_assistant.py

@@ -2,6 +2,7 @@
 import functools
 import logging
 import os
+import sys
 
 from devassistant import argument
 from devassistant import assistant_base
@@ -27,6 +28,9 @@ def inner(self, *args, **kwargs):
 
     return inner
 
+if sys.version_info[0] > 2:
+    basestring = str
+
 class YamlAssistant(assistant_base.AssistantBase, loaded_yaml.LoadedYaml):
     def __init__(self, name, parsed_yaml, path, fully_loaded=True, role='crt'):
         self.name = name
@@ -296,17 +300,7 @@ def _run_one_section(self, section, kwargs):
                     skip_else = False
                 elif comm_type.startswith('for'):
                     # syntax: "for $i in $x: <section> or "for $i in cl_command: <section>"
-                    try:
-                        control_var, expression = self._parse_for(comm_type)
-                    except exceptions.YamlSyntaxError as e:
-                        logger.error(e)
-                        raise e
-                    try:
-                        eval_expression = self._evaluate(expression, **kwargs)[1]
-                    except exceptions.YamlSyntaxError as e:
-                        logger.log(e)
-                        raise e
-
+                    control_var, eval_expression = self._get_for_control_var_and_eval_expr(comm_type, **kwargs)
                     for i in eval_expression:
                         kwargs[control_var] = i
                         self._run_one_section(comm, kwargs)
@@ -352,6 +346,29 @@ def _parse_for(self, control_line, **kwargs):
 
         return (control_var, for_parts[3])
 
+    def _get_for_control_var_and_eval_expr(self, comm_type, **kwargs):
+        """Returns tuple that consists of control variable name and iterable that is result
+        of evaluated expression of given for loop.
+
+        For example:
+        - given 'for $i in $(echo "foo bar")' it returns ('i', ['foo', 'bar'])
+        """
+        try:
+            control_var, expression = self._parse_for(comm_type)
+        except exceptions.YamlSyntaxError as e:
+            logger.error(e)
+            raise e
+        try:
+            eval_expression = self._evaluate(expression, **kwargs)[1]
+        except exceptions.YamlSyntaxError as e:
+            logger.log(e)
+            raise e
+
+        iterval = []
+        if isinstance(eval_expression, basestring):
+            iterval = eval_expression.split()
+        return control_var, iterval
+
     def _get_section_from_condition(self, if_section, else_section=None, **kwargs):
         """Returns section that should be used from given if/else sections by evaluating given condition.
 

test/test_yaml_assistant.py

@@ -227,6 +227,17 @@ def test_default_icon_path(self):
         self.ya.path = os.path.join(settings.DATA_DIRECTORIES[0], 'assistants/crt/bar/baz.yaml')
         assert self.ya.default_icon_path == os.path.join(settings.DATA_DIRECTORIES[0], 'icons/crt/bar/baz.svg')
 
+    def test_loop_empty_string(self):
+        self.ya._run = [{'for $i in $(echo "")': [{'log_i': '$i'}]}]
+        self.ya.run()
+        assert 'INFO' not in map(lambda x: x[0], self.tlh.msgs)
+
+    def test_loop_words(self):
+        self.ya._run = [{'for $i in $(echo "foo bar")': [{'log_i': '$i'}]}]
+        self.ya.run()
+        assert ('INFO', 'foo') in self.tlh.msgs
+        assert ('INFO', 'bar') in self.tlh.msgs
+
 
 class TestExpressions(TestYamlAssistant):
     def test_assign_existing_nonempty_variable(self):