fix #176 - implement Decimal fixed-point support

* fix decimal precision issue

* fix other float to Decimal

* fix float precision

* add test

* clean up

* fix bug

* expand test

* fix test to get around weird precision issues in python2.7

* lint

* respond to comments

---------

Co-authored-by: Sergey Astanin <s.astanin@gmail.com>

Author: mvadari

tabulate/__init__.py

@@ -13,6 +13,7 @@
 import warnings
 from collections import namedtuple
 from collections.abc import Iterable, Sized
+from decimal import Decimal
 from html import escape as htmlescape
 from itertools import chain, zip_longest as izip_longest
 from functools import reduce, partial
@@ -1356,6 +1357,8 @@ def _format(val, valtype, floatfmt, intfmt, missingval="", has_invisible=True):
         else:
             if isinstance(val, str) and "," in val:
                 val = val.replace(",", "")  # handle thousands-separators
+            if isinstance(val, Decimal):
+                return format(val, floatfmt)
             try:
                 return format(float(val), floatfmt)
             except (ValueError, TypeError):

test/test_output.py

@@ -1,5 +1,6 @@
 """Test output of the various forms of tabular data."""
 
+from decimal import Decimal
 from pytest import mark
 
 from common import assert_equal, raises, skip, check_warnings
@@ -2857,6 +2858,16 @@ def test_floatfmt_multi():
     assert_equal(expected, result)
 
 
+def test_floatfmt_decimal():
+    result = tabulate(
+        [[Decimal("99999998999.999980"), 1234.5, 1.2345678, "inf"]],
+        floatfmt=".6f",
+        tablefmt="plain",
+    )
+    expected = "99999998999.999980  1234.500000  1.234568  inf"
+    assert_equal(expected, result)
+
+
 def test_colalign_multi():
     "Output: string columns with custom colalign"
     result = tabulate([["one", "two"], ["three", "four"]], colalign=("right",), tablefmt="plain")