output generator

CHANGELOG

@@ -1,6 +1,11 @@
 Changelog
 =========
 
+TBD
+---
+
+* Output as generator
+
 Version 0.2.3
 -------------
 

cli_helpers/tabular_output/delimited_output_adapter.py

@@ -12,25 +12,37 @@
 preprocessors = (override_missing_value, bytes_to_string)
 
 
+class linewriter(object):
+    def __init__(self):
+        self.reset()
+
+    def reset(self):
+        self.line = None
+
+    def write(self, d):
+        self.line = d
+
+
 def adapter(data, headers, table_format='csv', **kwargs):
     """Wrap the formatting inside a function for TabularOutputFormatter."""
     keys = ('dialect', 'delimiter', 'doublequote', 'escapechar',
-            'lineterminator', 'quotechar', 'quoting', 'skipinitialspace',
-            'strict')
+            'quotechar', 'quoting', 'skipinitialspace', 'strict')
     if table_format == 'csv':
         delimiter = ','
     elif table_format == 'tsv':
         delimiter = '\t'
     else:
         raise ValueError('Invalid table_format specified.')
 
-    ckwargs = {'delimiter': delimiter}
+    ckwargs = {'delimiter': delimiter, 'lineterminator': ''}
     ckwargs.update(filter_dict_by_key(kwargs, keys))
 
-    with contextlib.closing(StringIO()) as content:
-        writer = csv.writer(content, **ckwargs)
-        writer.writerow(headers)
-        for row in data:
-            writer.writerow(row)
+    l = linewriter()
+    writer = csv.writer(l, **ckwargs)
+    writer.writerow(headers)
+    yield l.line
 
-        return content.getvalue()
+    for row in data:
+        l.reset()
+        writer.writerow(row)
+        yield l.line

cli_helpers/tabular_output/tabulate_adapter.py

@@ -27,4 +27,4 @@ def adapter(data, headers, table_format=None, preserve_whitespace=False,
 
     tabulate.PRESERVE_WHITESPACE = preserve_whitespace
 
-    return tabulate.tabulate(data, headers, **tkwargs)
+    return iter(tabulate.tabulate(data, headers, **tkwargs).split('\n'))

cli_helpers/tabular_output/terminaltables_adapter.py

@@ -25,4 +25,10 @@ def adapter(data, headers, table_format=None, **kwargs):
     table = table_format_handler[table_format]
 
     t = table([headers] + list(data), **filter_dict_by_key(kwargs, keys))
-    return t.table
+
+    dimensions = terminaltables.width_and_alignment.max_dimensions(
+        t.table_data,
+        t.padding_left,
+        t.padding_right)[:3]
+    for r in t.gen_table(*dimensions):
+        yield ''.join(r)

cli_helpers/tabular_output/vertical_table_adapter.py

@@ -57,11 +57,7 @@ def vertical_table(data, headers, sep_title='{n}. row', sep_character='*',
 
     output = []
     for i, result in enumerate(formatted_rows):
-        output.append(_get_separator(i, sep_title, sep_character, sep_length))
-        output.append(result)
-        output.append('\n')
-
-    return ''.join(output)
+        yield _get_separator(i, sep_title, sep_character, sep_length) + result
 
 
 def adapter(data, headers, **kwargs):

tests/tabular_output/test_delimited_output_adapter.py

@@ -15,33 +15,34 @@ def test_csv_wrapper():
     data = [['abc', '1'], ['d', '456']]
     headers = ['letters', 'number']
     output = delimited_output_adapter.adapter(iter(data), headers)
-    assert output == dedent('''\
-        letters,number\r\n\
-        abc,1\r\n\
-        d,456\r\n''')
+    assert "\n".join(output) == dedent('''\
+        letters,number\n\
+        abc,1\n\
+        d,456''')
 
     # Test tab-delimited output.
     data = [['abc', '1'], ['d', '456']]
     headers = ['letters', 'number']
     output = delimited_output_adapter.adapter(
         iter(data), headers, table_format='tsv')
-    assert output == dedent('''\
-        letters\tnumber\r\n\
-        abc\t1\r\n\
-        d\t456\r\n''')
+    assert "\n".join(output) == dedent('''\
+        letters\tnumber\n\
+        abc\t1\n\
+        d\t456''')
 
     with pytest.raises(ValueError):
         output = delimited_output_adapter.adapter(
             iter(data), headers, table_format='foobar')
+        list(output)
 
 
 def test_unicode_with_csv():
     """Test that the csv wrapper can handle non-ascii characters."""
     data = [['观音', '1'], ['Ποσειδῶν', '456']]
     headers = ['letters', 'number']
     output = delimited_output_adapter.adapter(data, headers)
-    assert output == dedent('''\
-        letters,number\r\n\
-        观音,1\r\n\
-        Ποσειδῶν,456\r\n''')
+    assert "\n".join(output) == dedent('''\
+        letters,number\n\
+        观音,1\n\
+        Ποσειδῶν,456''')
 

tests/tabular_output/test_output_formatter.py

@@ -26,8 +26,8 @@ def test_tabular_output_formatter():
         | hi   | 1.1     |
         +------+---------+''')
 
-    assert expected == TabularOutputFormatter().format_output(
-        iter(data), headers, format_name='ascii')
+    assert expected == "\n".join(TabularOutputFormatter().format_output(
+        iter(data), headers, format_name='ascii'))
 
 
 def test_tabular_format_output_wrapper():
@@ -44,8 +44,8 @@ def test_tabular_format_output_wrapper():
         | 3  | Joe  |
         +----+------+''')
 
-    assert expected == format_output(iter(data), headers, format_name='ascii',
-                                     missing_value='N/A')
+    assert expected == "\n".join(format_output(iter(data), headers, format_name='ascii',
+                                               missing_value='N/A'))
 
 
 def test_additional_preprocessors():
@@ -70,9 +70,9 @@ def hello_world_data(data):
         | hello! | hello, world |
         +--------+--------------+''')
 
-    assert expected == TabularOutputFormatter().format_output(
+    assert expected == "\n".join(TabularOutputFormatter().format_output(
         iter(data), headers, format_name='ascii', preprocessors=(hello_world,),
-        missing_value='hello')
+        missing_value='hello'))
 
 
 def test_format_name_attribute():
@@ -108,7 +108,10 @@ def test_tabulate_ansi_escape_in_default_value():
                            missing_value='\x1b[38;5;10mNULL\x1b[39m')
     unstyled = format_output(iter(data), headers, format_name='psql',
                              missing_value='NULL')
-    assert strip_ansi(styled) == unstyled
+
+    stripped_styled = [strip_ansi(s) for s in styled]
+
+    assert list(unstyled) == stripped_styled
 
 
 def test_get_type():
@@ -144,5 +147,8 @@ def test_enforce_iterable():
 
     for format_name in formatter.supported_formats:
         formatter.format_name = format_name
-        formatted = formatter.format_output(zip(loremipsum), ['lorem'])
-        assert len(formatted) > 0
+        try:
+            formatted = next(formatter.format_output(
+                zip(loremipsum), ['lorem']))
+        except TypeError:
+            assert False, "{0} doesn't return iterable".format(format_name)

tests/tabular_output/test_tabulate_adapter.py

@@ -12,7 +12,7 @@ def test_tabulate_wrapper():
     data = [['abc', 1], ['d', 456]]
     headers = ['letters', 'number']
     output = tabulate_adapter.adapter(iter(data), headers, table_format='psql')
-    assert output == dedent('''\
+    assert "\n".join(output) == dedent('''\
         +-----------+----------+
         | letters   |   number |
         |-----------+----------|
@@ -26,7 +26,7 @@ def test_markup_format():
     data = [['abc', 1], ['d', 456]]
     headers = ['letters', 'number']
     output = tabulate_adapter.adapter(iter(data), headers, table_format='mediawiki')
-    assert output == dedent('''\
+    assert "\n".join(output) == dedent('''\
         {| class="wikitable" style="text-align: left;"
         |+ <!-- caption -->
         |-

tests/tabular_output/test_terminaltables_adapter.py

@@ -13,7 +13,7 @@ def test_terminal_tables_adapter():
     headers = ['letters', 'number']
     output = terminaltables_adapter.adapter(
         iter(data), headers, table_format='ascii')
-    assert output == dedent('''\
+    assert "\n".join(output) == dedent('''\
         +---------+--------+
         | letters | number |
         +---------+--------+

tests/tabular_output/test_vertical_table_adapter.py

@@ -17,9 +17,9 @@ def test_vertical_table():
         age  | 123
         ***************************[ 2. row ]***************************
         name | world
-        age  | 456
-        """)
-    assert expected == vertical_table_adapter.adapter(results, ('name', 'age'))
+        age  | 456""")
+    assert expected == "\n".join(
+        vertical_table_adapter.adapter(results, ('name', 'age')))
 
 
 def test_vertical_table_customized():
@@ -32,8 +32,7 @@ def test_vertical_table_customized():
         age  | 47
         -[ PERSON 2 ]-----
         name | jill
-        age  | 50
-        """)
-    assert expected == vertical_table_adapter.adapter(
+        age  | 50""")
+    assert expected == "\n".join(vertical_table_adapter.adapter(
         results, ('name', 'age'), sep_title='PERSON {n}',
-        sep_character='-', sep_length=(1, 5))
+        sep_character='-', sep_length=(1, 5)))