Add note about csvcut truncating long rows, #992

docs/scripts/csvcut.rst

@@ -41,6 +41,10 @@ See also: :doc:`../common_arguments`.
 
     csvcut does not implement row filtering, for this you should pipe data to :doc:`csvgrep`.
 
+.. note::
+
+    If a data row is longer than the header row, its additional columns are truncated. Use :doc:`csvclean` first to fix such rows.
+
 Examples
 ========
 
@@ -71,7 +75,6 @@ Print only the names of all columns, by removing the indices with the :code:`cut
     Post-Vietnam Era Veteran's Educational Assistance Program
     TOTAL
 
-
 Extract the first and third columns::
 
     csvcut -c 1,3 examples/realdata/FY09_EDU_Recipients_by_State.csv
@@ -92,4 +95,3 @@ Extract a column that may not exist in all files::
 Display a column's unique values::
 
     csvcut -c 1 examples/realdata/FY09_EDU_Recipients_by_State.csv | sed 1d | sort | uniq
-

tests/test_utilities/test_csvcut.py

@@ -70,7 +70,21 @@ def test_no_header_row(self):
 
     def test_ragged(self):
         # Test that csvcut doesn't error when a row is short.
-        self.get_output(['-c', 'column_c', 'examples/bad.csv'])
+        self.assertRows(['-c', 'column_c', 'examples/bad.csv'], [
+            ['column_c'],
+            [],
+            [],
+            ['17'],
+        ])
+
+    def test_truncate(self):
+        # Test that csvcut truncates long rows.
+        self.assertRows(['-C', 'column_a,column_b', 'examples/bad.csv'], [
+            ['column_c'],
+            [],
+            [],
+            ['17'],
+        ])
 
     def test_names_with_skip_lines(self):
         self.assertLines(['--names', '--skip-lines', '3', 'examples/test_skip_lines.csv'], [