Store imported metadata in a sane order [fix psss#86]

tmt/base.py

@@ -102,20 +102,25 @@ class Test(Node):
 
     # Supported attributes (listed in display order)
     _keys = [
+        # Basic test information
         'summary',
         'description',
         'contact',
         'component',
+
+        # Test execution data
         'test',
         'path',
-        'duration',
-        'environment',
         'require',
-        'relevancy',
+        'environment',
+        'duration',
+        'enabled',
+        'result',
+
+        # Filtering attributes
         'tag',
         'tier',
-        'result',
-        'enabled',
+        'relevancy',
         ]
 
     def __init__(self, data, name=None):

tmt/convert.py

@@ -358,13 +358,18 @@ def read_nitrate(beaker_task, common_data, disabled):
 
 def write(path, data):
     """ Write gathered metadata in the fmf format """
+    # Put keys into a reasonable order
+    extra_keys = ['extra-summary', 'extra-task', 'extra-nitrate']
+    sorted_data = dict()
+    for key in tmt.base.Test._keys + extra_keys:
+        try:
+            sorted_data[key] = data[key]
+        except KeyError:
+            pass
     # Store metadata into a fmf file
     try:
         with open(path, 'w', encoding='utf-8') as fmf_file:
-            yaml.safe_dump(
-                data, fmf_file,
-                encoding='utf-8', allow_unicode=True,
-                indent=4, default_flow_style=False)
+            fmf_file.write(tmt.utils.dict_to_yaml(sorted_data))
     except IOError:
         raise ConvertError("Unable to write '{0}'".format(path))
     echo(style(

tmt/utils.py

@@ -357,11 +357,11 @@ def variables_to_dictionary(variables):
     return result
 
 
-def dict_to_yaml(data, width=None):
+def dict_to_yaml(data, width=None, sort=False):
     """ Convert dictionary into yaml """
     output = io.StringIO()
     yaml.safe_dump(
-        data, output,
+        data, output, sort_keys=sort,
         encoding='utf-8', allow_unicode=True,
         width=width, indent=4, default_flow_style=False)
     return output.getvalue()