csvformat: Add a --skip-header option, closes #929

CHANGELOG.rst

@@ -1,6 +1,7 @@
 Unreleased
 ----------
 
+* :doc:`/scripts/csvformat` adds a :code:`--skip-header` option to not output a header row.
 * :doc:`/scripts/csvstat` adds a :code:`--json` option to output results as JSON text.
 * :doc:`/scripts/csvstat` adds an :code:`--indent` option to indent the JSON text when :code:`--json` is set.
 * :doc:`/scripts/csvstat` reports a "Non-null values" statistic (or a :code:`nonnulls` column when :code:`--csv` is set).

csvkit/utilities/csvformat.py

@@ -12,6 +12,9 @@ class CSVFormat(CSVKitUtility):
     override_flags = ['L', 'blanks', 'date-format', 'datetime-format']
 
     def add_arguments(self):
+        self.argparser.add_argument(
+            '--skip-header', dest='skip_header', action='store_true',
+            help='Do not output a header row.')
         self.argparser.add_argument(
             '-D', '--out-delimiter', dest='out_delimiter',
             help='Delimiting character of the output CSV file.')
@@ -63,9 +66,11 @@ def main(self):
         if self.args.no_header_row:
             # Peek at a row to get the number of columns.
             _row = next(reader)
-            reader = itertools.chain([_row], reader)
             headers = make_default_headers(len(_row))
-            writer.writerow(headers)
+            reader = itertools.chain([headers, _row], reader)
+
+        if self.args.skip_header:
+            next(reader)
 
         writer.writerows(reader)
 

docs/scripts/csvformat.rst

@@ -24,6 +24,7 @@ Convert a CSV file to a custom output format.:
 
    optional arguments:
      -h, --help            show this help message and exit
+     --skip-header         Do not output a header row.
      -D OUT_DELIMITER, --out-delimiter OUT_DELIMITER
                            Delimiting character of the output CSV file.
      -T, --out-tabs        Specify that the output CSV file is delimited with

tests/test_utilities/test_csvformat.py

@@ -19,6 +19,16 @@ def test_skip_lines(self):
             '1|2|3',
         ])
 
+    def test_skip_header(self):
+        self.assertLines(['--skip-header', 'examples/dummy.csv'], [
+            '1,2,3',
+        ])
+
+    def test_skip_header_no_header_row(self):
+        self.assertLines(['--no-header-row', '--skip-header', 'examples/no_header_row.csv'], [
+            '1,2,3',
+        ])
+
     def test_no_header_row(self):
         self.assertLines(['--no-header-row', 'examples/no_header_row.csv'], [
             'a,b,c',