BUG: long int formatting with thousands separator (pandas-dev#53017)

Co-authored-by: JHM Darbyshire (iMac) <[email protected]>

pandas/io/formats/style_render.py

@@ -1747,7 +1747,7 @@ def _default_formatter(x: Any, precision: int, thousands: bool = False) -> Any:
     if is_float(x) or is_complex(x):
         return f"{x:,.{precision}f}" if thousands else f"{x:.{precision}f}"
     elif is_integer(x):
-        return f"{x:,.0f}" if thousands else str(x)
+        return f"{x:,}" if thousands else str(x)
     return x
 
 

pandas/tests/io/formats/style/test_format.py

@@ -416,6 +416,17 @@ def test_str_escape_error():
     _str_escape(2.00, "bad_escape")  # OK since dtype is float
 
 
+def test_long_int_formatting():
+    df = DataFrame(data=[[1234567890123456789]], columns=["test"])
+    styler = df.style
+    ctx = styler._translate(True, True)
+    assert ctx["body"][0][1]["display_value"] == "1234567890123456789"
+
+    styler = df.style.format(thousands="_")
+    ctx = styler._translate(True, True)
+    assert ctx["body"][0][1]["display_value"] == "1_234_567_890_123_456_789"
+
+
 def test_format_options():
     df = DataFrame({"int": [2000, 1], "float": [1.009, None], "str": ["&<", "&~"]})
     ctx = df.style._translate(True, True)

pandas/tests/io/formats/test_to_html.py

@@ -896,11 +896,3 @@ def test_to_html_float_format_object_col(datapath):
     result = df.to_html(float_format=lambda x: f"{x:,.0f}")
     expected = expected_html(datapath, "gh40024_expected_output")
     assert result == expected
-
-
-def test_to_html_float_point_double(datapath):
-    # GH#52272
-    df = DataFrame(data=[[1234567890123456789]], columns=["test"])
-    result = df.to_html()
-    expected = expected_html(datapath, "gh52272_expected_output")
-    assert result == expected

pandas/tests/io/formats/test_to_latex.py

@@ -1407,16 +1407,3 @@ def test_to_latex_multiindex_multirow(self):
             """
         )
         assert result == expected
-
-
-def test_to_latex_exceeding_float_point_double():
-    df = DataFrame(data=[[1234567890123456789]], columns=["test"])
-    expected = _dedent(
-        r"""
-        \begin{tabular}{lr}
-         & test \\
-        0 & 1234567890123456789 \\
-        \end{tabular}
-        """
-    )
-    assert df.style.to_latex() == expected