CLN: replacing '.format' with f-strings in various files

pandas/tests/util/test_validate_args.py

@@ -20,10 +20,8 @@ def test_bad_arg_length_max_value_single():
     max_length = len(compat_args) + min_fname_arg_count
     actual_length = len(args) + min_fname_arg_count
     msg = (
-        r"{fname}\(\) takes at most {max_length} "
-        r"argument \({actual_length} given\)".format(
-            fname=_fname, max_length=max_length, actual_length=actual_length
-        )
+        fr"{_fname}\(\) takes at most {max_length} "
+        fr"argument \({actual_length} given\)"
     )
 
     with pytest.raises(TypeError, match=msg):
@@ -38,10 +36,8 @@ def test_bad_arg_length_max_value_multiple():
     max_length = len(compat_args) + min_fname_arg_count
     actual_length = len(args) + min_fname_arg_count
     msg = (
-        r"{fname}\(\) takes at most {max_length} "
-        r"arguments \({actual_length} given\)".format(
-            fname=_fname, max_length=max_length, actual_length=actual_length
-        )
+        fr"{_fname}\(\) takes at most {max_length} "
+        fr"arguments \({actual_length} given\)"
     )
 
     with pytest.raises(TypeError, match=msg):
@@ -52,8 +48,8 @@ def test_bad_arg_length_max_value_multiple():
 def test_not_all_defaults(i):
     bad_arg = "foo"
     msg = (
-        "the '{arg}' parameter is not supported "
-        r"in the pandas implementation of {func}\(\)".format(arg=bad_arg, func=_fname)
+        f"the '{bad_arg}' parameter is not supported "
+        fr"in the pandas implementation of {_fname}\(\)"
     )
 
     compat_args = {"foo": 2, "bar": -1, "baz": 3}

pandas/tests/util/test_validate_kwargs.py

@@ -22,8 +22,8 @@ def test_bad_kwarg():
 def test_not_all_none(i):
     bad_arg = "foo"
     msg = (
-        r"the '{arg}' parameter is not supported "
-        r"in the pandas implementation of {func}\(\)".format(arg=bad_arg, func=_fname)
+        fr"the '{bad_arg}' parameter is not supported "
+        fr"in the pandas implementation of {_fname}\(\)"
     )
 
     compat_args = {"foo": 1, "bar": "s", "baz": None}

pandas/tests/window/test_window.py

@@ -65,7 +65,7 @@ def test_agg_function_support(self, arg):
         df = pd.DataFrame({"A": np.arange(5)})
         roll = df.rolling(2, win_type="triang")
 
-        msg = "'{arg}' is not a valid function for 'Window' object".format(arg=arg)
+        msg = f"'{arg}' is not a valid function for 'Window' object"
         with pytest.raises(AttributeError, match=msg):
             roll.agg(arg)
 

pandas/tseries/holiday.py

@@ -186,16 +186,16 @@ class from pandas.tseries.offsets
     def __repr__(self) -> str:
         info = ""
         if self.year is not None:
-            info += "year={year}, ".format(year=self.year)
-        info += "month={mon}, day={day}, ".format(mon=self.month, day=self.day)
+            info += f"year={self.year}, "
+        info += f"month={self.month}, day={self.day}, "
 
         if self.offset is not None:
-            info += "offset={offset}".format(offset=self.offset)
+            info += f"offset={self.offset}"
 
         if self.observance is not None:
-            info += "observance={obs}".format(obs=self.observance)
+            info += f"observance={self.observance}"
 
-        repr = "Holiday: {name} ({info})".format(name=self.name, info=info)
+        repr = f"Holiday: {self.name} ({info})"
         return repr
 
     def dates(self, start_date, end_date, return_name=False):
@@ -394,8 +394,7 @@ def holidays(self, start=None, end=None, return_name=False):
         """
         if self.rules is None:
             raise Exception(
-                "Holiday Calendar {name} does not have any "
-                "rules specified".format(name=self.name)
+                f"Holiday Calendar {self.name} does not have any " "rules specified"
             )
 
         if start is None:

scripts/download_wheels.py

@@ -26,7 +26,7 @@ def fetch(version):
     files = [
         x
         for x in root.xpath("//a/text()")
-        if x.startswith("pandas-{}".format(version)) and not dest.joinpath(x).exists()
+        if x.startswith(f"pandas-{version}") and not dest.joinpath(x).exists()
     ]
 
     N = len(files)
@@ -35,9 +35,7 @@ def fetch(version):
         out = str(dest.joinpath(filename))
         link = urllib.request.urljoin(base, filename)
         urllib.request.urlretrieve(link, out)
-        print(
-            "Downloaded {link} to {out} [{i}/{N}]".format(link=link, out=out, i=i, N=N)
-        )
+        print(f"Downloaded {link} to {out} [{i}/{N}]")
 
 
 def main(args=None):

scripts/generate_pip_deps_from_conda.py

@@ -127,13 +127,13 @@ def main(conda_fname, pip_fname, compare=False):
     )
     if res:
         msg = (
-            "`requirements-dev.txt` has to be generated with `{}` after "
-            "`environment.yml` is modified.\n".format(sys.argv[0])
+            f"`requirements-dev.txt` has to be generated with `{sys.argv[0]}` after "
+            "`environment.yml` is modified.\n"
         )
         if args.azure:
             msg = (
                 "##vso[task.logissue type=error;"
-                "sourcepath=requirements-dev.txt]{}".format(msg)
+                f"sourcepath=requirements-dev.txt]{msg}"
             )
         sys.stderr.write(msg)
     sys.exit(res)

scripts/tests/test_validate_docstrings.py

@@ -1300,7 +1300,7 @@ def test_resolves_class_name(self, name, expected_obj):
 
     @pytest.mark.parametrize("invalid_name", ["panda", "panda.DataFrame"])
     def test_raises_for_invalid_module_name(self, invalid_name):
-        msg = 'No module can be imported from "{}"'.format(invalid_name)
+        msg = f'No module can be imported from "{invalid_name}"'
         with pytest.raises(ImportError, match=msg):
             validate_docstrings.Docstring(invalid_name)
 
@@ -1310,7 +1310,7 @@ def test_raises_for_invalid_module_name(self, invalid_name):
     def test_raises_for_invalid_attribute_name(self, invalid_name):
         name_components = invalid_name.split(".")
         obj_name, invalid_attr_name = name_components[-2], name_components[-1]
-        msg = "'{}' has no attribute '{}'".format(obj_name, invalid_attr_name)
+        msg = f"'{obj_name}' has no attribute '{invalid_attr_name}'"
         with pytest.raises(AttributeError, match=msg):
             validate_docstrings.Docstring(invalid_name)
 

scripts/validate_docstrings.py

@@ -357,7 +357,7 @@ def source_file_def_line(self):
     @property
     def github_url(self):
         url = "https://github.com/pandas-dev/pandas/blob/master/"
-        url += "{}#L{}".format(self.source_file_name, self.source_file_def_line)
+        url += f"{self.source_file_name}#L{self.source_file_def_line}"
         return url
 
     @property
@@ -501,7 +501,7 @@ def parameter_desc(self, param):
         desc = self.doc_parameters[param][1]
         # Find and strip out any sphinx directives
         for directive in DIRECTIVES:
-            full_directive = ".. {}".format(directive)
+            full_directive = f".. {directive}"
             if full_directive in desc:
                 # Only retain any description before the directive
                 desc = desc[: desc.index(full_directive)]
@@ -825,14 +825,12 @@ def get_validation_data(doc):
                     "EX03",
                     error_code=err.error_code,
                     error_message=err.message,
-                    times_happening=" ({} times)".format(err.count)
-                    if err.count > 1
-                    else "",
+                    times_happening=f" ({err.count} times)" if err.count > 1 else "",
                 )
             )
         examples_source_code = "".join(doc.examples_source_code)
         for wrong_import in ("numpy", "pandas"):
-            if "import {}".format(wrong_import) in examples_source_code:
+            if f"import {wrong_import}" in examples_source_code:
                 errs.append(error("EX04", imported_library=wrong_import))
     return errs, wrns, examples_errs
 
@@ -920,7 +918,7 @@ def validate_all(prefix, ignore_deprecated=False):
     api_item_names = set(list(zip(*api_items))[0])
     for class_ in (pandas.Series, pandas.DataFrame):
         for member in inspect.getmembers(class_):
-            func_name = "pandas.{}.{}".format(class_.__name__, member[0])
+            func_name = f"pandas.{class_.__name__}.{member[0]}"
             if not member[0].startswith("_") and func_name not in api_item_names:
                 if prefix and not func_name.startswith(prefix):
                     continue
@@ -938,13 +936,9 @@ def header(title, width=80, char="#"):
         full_line = char * width
         side_len = (width - len(title) - 2) // 2
         adj = "" if len(title) % 2 == 0 else " "
-        title_line = "{side} {title}{adj} {side}".format(
-            side=char * side_len, title=title, adj=adj
-        )
+        title_line = f"{char * side_len} {title}{adj} {char * side_len}"
 
-        return "\n{full_line}\n{title_line}\n{full_line}\n\n".format(
-            full_line=full_line, title_line=title_line
-        )
+        return f"\n{full_line}\n{title_line}\n{full_line}\n\n"
 
     exit_status = 0
     if func_name is None:
@@ -986,24 +980,24 @@ def header(title, width=80, char="#"):
 
     else:
         result = validate_one(func_name)
-        sys.stderr.write(header("Docstring ({})".format(func_name)))
-        sys.stderr.write("{}\n".format(result["docstring"]))
+        sys.stderr.write(header(f"Docstring ({func_name})"))
+        sys.stderr.write(f"{result['docstring']}\n")
         sys.stderr.write(header("Validation"))
         if result["errors"]:
-            sys.stderr.write("{} Errors found:\n".format(len(result["errors"])))
+            sys.stderr.write(f"{len(result['errors'])} Errors found:\n")
             for err_code, err_desc in result["errors"]:
                 # Failing examples are printed at the end
                 if err_code == "EX02":
                     sys.stderr.write("\tExamples do not pass tests\n")
                     continue
-                sys.stderr.write("\t{}\n".format(err_desc))
+                sys.stderr.write(f"\t{err_desc}\n")
         if result["warnings"]:
-            sys.stderr.write("{} Warnings found:\n".format(len(result["warnings"])))
+            sys.stderr.write(f"{len(result['warnings'])} Warnings found:\n")
             for wrn_code, wrn_desc in result["warnings"]:
-                sys.stderr.write("\t{}\n".format(wrn_desc))
+                sys.stderr.write(f"\t{wrn_desc}\n")
 
         if not result["errors"]:
-            sys.stderr.write('Docstring for "{}" correct. :)\n'.format(func_name))
+            sys.stderr.write(f'Docstring for "{func_name}" correct. :)\n')
 
         if result["examples_errors"]:
             sys.stderr.write(header("Doctests"))
@@ -1027,7 +1021,7 @@ def header(title, width=80, char="#"):
         choices=format_opts,
         help="format of the output when validating "
         "multiple docstrings (ignored when validating one)."
-        "It can be {}".format(str(format_opts)[1:-1]),
+        f"It can be {str(format_opts)[1:-1]}",
     )
     argparser.add_argument(
         "--prefix",