style: prefer explicit string concatenation

14 files changed, 133 insertions, 140 deletions

diff --git a/coverage/cmdline.py b/coverage/cmdline.py
index eae22f2f..1be155b8 100644
--- a/coverage/cmdline.py
+++ b/coverage/cmdline.py
@@ -45,7 +45,7 @@ class Opts:
         '', '--concurrency', action='store', metavar="LIB",
         choices=CONCURRENCY_CHOICES,
         help=(
-            "Properly measure code using a concurrency library. "
+            "Properly measure code using a concurrency library. " +
             "Valid values are: {}."
         ).format(", ".join(CONCURRENCY_CHOICES)),
     )
@@ -77,20 +77,20 @@ class Opts:
         '', '--include', action='store',
         metavar="PAT1,PAT2,...",
         help=(
-            "Include only files whose paths match one of these patterns. "
+            "Include only files whose paths match one of these patterns. " +
             "Accepts shell-style wildcards, which must be quoted."
         ),
     )
     pylib = optparse.make_option(
         '-L', '--pylib', action='store_true',
         help=(
-            "Measure coverage even inside the Python installed library, "
+            "Measure coverage even inside the Python installed library, " +
             "which isn't done by default."
         ),
     )
     sort = optparse.make_option(
         '--sort', action='store', metavar='COLUMN',
-        help="Sort the report by the named column: name, stmts, miss, branch, brpart, or cover. "
+        help="Sort the report by the named column: name, stmts, miss, branch, brpart, or cover. " +
              "Default is name."
     )
     show_missing = optparse.make_option(
@@ -117,7 +117,7 @@ class Opts:
         '', '--omit', action='store',
         metavar="PAT1,PAT2,...",
         help=(
-            "Omit files whose paths match one of these patterns. "
+            "Omit files whose paths match one of these patterns. " +
             "Accepts shell-style wildcards, which must be quoted."
         ),
     )
@@ -125,7 +125,7 @@ class Opts:
         '', '--contexts', action='store',
         metavar="REGEX1,REGEX2,...",
         help=(
-            "Only display data from lines covered in the given contexts. "
+            "Only display data from lines covered in the given contexts. " +
             "Accepts Python regexes, which must be quoted."
         ),
     )
@@ -146,30 +146,30 @@ class Opts:
     parallel_mode = optparse.make_option(
         '-p', '--parallel-mode', action='store_true',
         help=(
-            "Append the machine name, process id and random number to the "
-            ".coverage data file name to simplify collecting data from "
+            "Append the machine name, process id and random number to the " +
+            ".coverage data file name to simplify collecting data from " +
             "many processes."
         ),
     )
     module = optparse.make_option(
         '-m', '--module', action='store_true',
         help=(
-            "<pyfile> is an importable Python module, not a script path, "
+            "<pyfile> is an importable Python module, not a script path, " +
             "to be run as 'python -m' would run it."
         ),
     )
     precision = optparse.make_option(
         '', '--precision', action='store', metavar='N', type=int,
         help=(
-            "Number of digits after the decimal point to display for "
+            "Number of digits after the decimal point to display for " +
             "reported coverage percentages."
         ),
     )
     rcfile = optparse.make_option(
         '', '--rcfile', action='store',
         help=(
-            "Specify configuration file. "
-            "By default '.coveragerc', 'setup.cfg', 'tox.ini', and "
+            "Specify configuration file. " +
+            "By default '.coveragerc', 'setup.cfg', 'tox.ini', and " +
             "'pyproject.toml' are tried. [env: COVERAGE_RCFILE]"
         ),
     )
@@ -180,7 +180,7 @@ class Opts:
     timid = optparse.make_option(
         '', '--timid', action='store_true',
         help=(
-            "Use a simpler but slower trace method. Try this if you get "
+            "Use a simpler but slower trace method. Try this if you get " +
             "seemingly impossible results!"
         ),
     )
@@ -328,7 +328,7 @@ CMDS = {
             ] + GLOBAL_ARGS,
         usage="[options] [modules]",
         description=(
-            "Make annotated copies of the given files, marking statements that are executed "
+            "Make annotated copies of the given files, marking statements that are executed " +
             "with > and statements that are missed with !."
         ),
     ),
@@ -341,11 +341,11 @@ CMDS = {
             ] + GLOBAL_ARGS,
         usage="[options] <path1> <path2> ... <pathN>",
         description=(
-            "Combine data from multiple coverage files collected "
-            "with 'run -p'.  The combined results are written to a single "
-            "file representing the union of the data. The positional "
-            "arguments are data files or directories containing data files. "
-            "If no paths are provided, data files in the default data file's "
+            "Combine data from multiple coverage files collected " +
+            "with 'run -p'.  The combined results are written to a single " +
+            "file representing the union of the data. The positional " +
+            "arguments are data files or directories containing data files. " +
+            "If no paths are provided, data files in the default data file's " +
             "directory are combined."
         ),
     ),
@@ -354,12 +354,12 @@ CMDS = {
         "debug", GLOBAL_ARGS,
         usage="<topic>",
         description=(
-            "Display information about the internals of coverage.py, "
-            "for diagnosing problems. "
-            "Topics are: "
-                "'data' to show a summary of the collected data; "
-                "'sys' to show installation information; "
-                "'config' to show the configuration; "
+            "Display information about the internals of coverage.py, " +
+            "for diagnosing problems. " +
+            "Topics are: " +
+                "'data' to show a summary of the collected data; " +
+                "'sys' to show installation information; " +
+                "'config' to show the configuration; " +
                 "'premain' to show what is calling coverage."
         ),
     ),
@@ -393,8 +393,8 @@ CMDS = {
             ] + GLOBAL_ARGS,
         usage="[options] [modules]",
         description=(
-            "Create an HTML report of the coverage of the files.  "
-            "Each file gets its own page, with the source decorated to show "
+            "Create an HTML report of the coverage of the files.  " +
+            "Each file gets its own page, with the source decorated to show " +
             "executed, excluded, and missed lines."
         ),
     ),
@@ -732,9 +732,9 @@ class CoverageScript:
                 # they will be None if they have not been specified.
                 if getattr(options, opt_name) is not None:
                     show_help(
-                        "Options affecting multiprocessing must only be specified "
-                        "in a configuration file.\n"
-                        "Remove --{} from the command line.".format(opt_name)
+                        "Options affecting multiprocessing must only be specified " +
+                        "in a configuration file.\n" +
+                        f"Remove --{opt_name} from the command line."
                     )
                     return ERR
 
diff --git a/coverage/execfile.py b/coverage/execfile.py
index f46955bc..539e368d 100644
--- a/coverage/execfile.py
+++ b/coverage/execfile.py
@@ -52,9 +52,8 @@ def find_module(modulename):
         spec = importlib.util.find_spec(mod_main)
         if not spec:
             raise NoSource(
-                "No module named %s; "
-                "%r is a package and cannot be directly executed"
-                % (mod_main, modulename)
+                f"No module named {mod_main}; " +
+                f"{modulename!r} is a package and cannot be directly executed"
             )
         pathname = spec.origin
         packagename = spec.name
diff --git a/coverage/parser.py b/coverage/parser.py
index 5c467a7e..3be822d5 100644
--- a/coverage/parser.py
+++ b/coverage/parser.py
@@ -367,7 +367,7 @@ class ByteParser:
         for attr in ['co_lnotab', 'co_firstlineno']:
             if not hasattr(self.code, attr):
                 raise StopEverything(                   # pragma: only jython
-                    "This implementation of Python doesn't support code analysis.\n"
+                    "This implementation of Python doesn't support code analysis.\n" +
                     "Run coverage.py under another Python for this command."
                 )
 
diff --git a/tests/test_arcs.py b/tests/test_arcs.py
index 5b7965aa..6cdc908e 100644
--- a/tests/test_arcs.py
+++ b/tests/test_arcs.py
@@ -517,8 +517,8 @@ class LoopArcTest(CoverageTest):
             branches_3([0,1])
             """,
             arcz=
-                ".1 18 8G GH H. "
-                ".2 23 34 43 26 3. 6. "
+                ".1 18 8G GH H. " +
+                ".2 23 34 43 26 3. 6. " +
                 "-89 9A 9-8 AB BC CB B9 AE E9",
             arcz_missing="26 6."
             )
@@ -1077,18 +1077,18 @@ class ExceptionArcTest(CoverageTest):
     def test_except_jump_finally(self):
         if env.PYBEHAVIOR.finally_jumps_back:
             arcz = (
-                ".1 1Q QR RS ST TU U. "
-                ".2 23 34 45 56 4O 6L "
-                "78 89 9A AL LA AO  8B BC CD DL LD D4  BE EF FG GL LG G.  EH HI IJ JL  HL "
-                "L4 LM "
+                ".1 1Q QR RS ST TU U. " +
+                ".2 23 34 45 56 4O 6L " +
+                "78 89 9A AL LA AO  8B BC CD DL LD D4  BE EF FG GL LG G.  EH HI IJ JL  HL " +
+                "L4 LM " +
                 "MN NO O."
             )
         else:
             arcz = (
-                ".1 1Q QR RS ST TU U. "
-                ".2 23 34 45 56 4O 6L "
-                "78 89 9A AL  8B BC CD DL  BE EF FG GL  EH HI IJ JL  HL "
-                "LO L4 L. LM "
+                ".1 1Q QR RS ST TU U. " +
+                ".2 23 34 45 56 4O 6L " +
+                "78 89 9A AL  8B BC CD DL  BE EF FG GL  EH HI IJ JL  HL " +
+                "LO L4 L. LM " +
                 "MN NO O."
             )
         self.check_coverage("""\
@@ -1131,18 +1131,18 @@ class ExceptionArcTest(CoverageTest):
     def test_else_jump_finally(self):
         if env.PYBEHAVIOR.finally_jumps_back:
             arcz = (
-                ".1 1S ST TU UV VW W. "
-                ".2 23 34 45 56 6A 78 8N 4Q "
-                "AB BC CN NC CQ  AD DE EF FN NF F4  DG GH HI IN NI I.  GJ JK KL LN  JN "
-                "N4 NO "
+                ".1 1S ST TU UV VW W. " +
+                ".2 23 34 45 56 6A 78 8N 4Q " +
+                "AB BC CN NC CQ  AD DE EF FN NF F4  DG GH HI IN NI I.  GJ JK KL LN  JN " +
+                "N4 NO " +
                 "OP PQ Q."
             )
         else:
             arcz = (
-                ".1 1S ST TU UV VW W. "
-                ".2 23 34 45 56 6A 78 8N 4Q "
-                "AB BC CN  AD DE EF FN  DG GH HI IN  GJ JK KL LN  JN "
-                "N4 NQ N. NO "
+                ".1 1S ST TU UV VW W. " +
+                ".2 23 34 45 56 6A 78 8N 4Q " +
+                "AB BC CN  AD DE EF FN  DG GH HI IN  GJ JK KL LN  JN " +
+                "N4 NQ N. NO " +
                 "OP PQ Q."
             )
         self.check_coverage("""\
@@ -1280,9 +1280,7 @@ class YieldTest(CoverageTest):
             next(gen)
             print(gen.send(6))
             """,
-            arcz=
-                ".1 17 78 89 9A AB B. "
-                ".2 23 34 45 52 2.",
+            arcz=".1 17 78 89 9A AB B. .2 23 34 45 52 2.",
             arcz_missing="2.",
         )
         assert self.stdout() == "20\n12\n"
@@ -1850,8 +1848,8 @@ class AsyncTest(CoverageTest):
             loop.close()                                    # G
             """,
             arcz=
-                ".1 13 38 8E EF FG G. "
-                "-34 45 56 6-3 "
+                ".1 13 38 8E EF FG G. " +
+                "-34 45 56 6-3 " +
                 "-89 9C C-8",
             arcz_unpredicted="5-3 9-8",
         )
diff --git a/tests/test_concurrency.py b/tests/test_concurrency.py
index 0b8d6a8b..696b12eb 100644
--- a/tests/test_concurrency.py
+++ b/tests/test_concurrency.py
@@ -187,15 +187,13 @@ def cant_trace_msg(concurrency, the_module):
         # We don't even have the underlying module installed, we expect
         # coverage to alert us to this fact.
         expected_out = (
-            "Couldn't trace with concurrency=%s, "
-            "the module isn't installed.\n" % concurrency
+            f"Couldn't trace with concurrency={concurrency}, the module isn't installed.\n"
         )
     elif env.C_TRACER or concurrency == "thread" or concurrency == "":
         expected_out = None
     else:
         expected_out = (
-            "Can't support concurrency=%s with PyTracer, "
-            "only threads are supported\n" % concurrency
+            f"Can't support concurrency={concurrency} with PyTracer, only threads are supported\n"
         )
     return expected_out
 
diff --git a/tests/test_config.py b/tests/test_config.py
index 9e126827..aec18bf2 100644
--- a/tests/test_config.py
+++ b/tests/test_config.py
@@ -169,14 +169,14 @@ class ConfigTest(CoverageTest):
             ("timid = 1\n", r"no section headers"),
             ("[run\n", r"\[run"),
             ("[report]\nexclude_lines = foo(\n",
-                r"Invalid \[report\].exclude_lines value 'foo\(': "
+                r"Invalid \[report\].exclude_lines value 'foo\(': " +
                 r"(unbalanced parenthesis|missing \))"),
             ("[report]\npartial_branches = foo[\n",
-                r"Invalid \[report\].partial_branches value 'foo\[': "
+                r"Invalid \[report\].partial_branches value 'foo\[': " +
                 r"(unexpected end of regular expression|unterminated character set)"),
             ("[report]\npartial_branches_always = foo***\n",
-                r"Invalid \[report\].partial_branches_always value "
-                r"'foo\*\*\*': "
+                r"Invalid \[report\].partial_branches_always value " +
+                r"'foo\*\*\*': " +
                 r"multiple repeat"),
         ]
 
@@ -190,14 +190,14 @@ class ConfigTest(CoverageTest):
         ("[tool.coverage.run]\ntimid = \"maybe?\"\n", r"maybe[?]"),
         ("[tool.coverage.run\n", None),
         ('[tool.coverage.report]\nexclude_lines = ["foo("]\n',
-         r"Invalid \[tool.coverage.report\].exclude_lines value u?'foo\(': "
+         r"Invalid \[tool.coverage.report\].exclude_lines value u?'foo\(': " +
          r"(unbalanced parenthesis|missing \))"),
         ('[tool.coverage.report]\npartial_branches = ["foo["]\n',
-         r"Invalid \[tool.coverage.report\].partial_branches value u?'foo\[': "
+         r"Invalid \[tool.coverage.report\].partial_branches value u?'foo\[': " +
          r"(unexpected end of regular expression|unterminated character set)"),
         ('[tool.coverage.report]\npartial_branches_always = ["foo***"]\n',
-         r"Invalid \[tool.coverage.report\].partial_branches_always value "
-         r"u?'foo\*\*\*': "
+         r"Invalid \[tool.coverage.report\].partial_branches_always value " +
+         r"u?'foo\*\*\*': " +
          r"multiple repeat"),
         ('[tool.coverage.run]\nconcurrency="foo"', "not a list"),
         ("[tool.coverage.report]\nprecision=1.23", "not an integer"),
diff --git a/tests/test_data.py b/tests/test_data.py
index 80cd9bc2..134eb55a 100644
--- a/tests/test_data.py
+++ b/tests/test_data.py
@@ -616,8 +616,8 @@ class CoverageDataFilesTest(DataTestHelpers, CoverageTest):
         self.assert_line_counts(covdata2, SUMMARY_1)
 
         assert re.search(
-            r"^Erasing data file '.*\.coverage'\n"
-            r"Creating data file '.*\.coverage'\n"
+            r"^Erasing data file '.*\.coverage'\n" +
+            r"Creating data file '.*\.coverage'\n" +
             r"Opening data file '.*\.coverage'\n$",
             debug.get_output()
         )
diff --git a/tests/test_files.py b/tests/test_files.py
index d6005d36..e5dd83bd 100644
--- a/tests/test_files.py
+++ b/tests/test_files.py
@@ -93,8 +93,8 @@ def test_flat_rootname(original, flat):
 
 
 @pytest.mark.parametrize(
-        "patterns, case_insensitive, partial,"
-            "matches,"
+        "patterns, case_insensitive, partial," +
+            "matches," +
             "nomatches",
 [
     (
diff --git a/tests/test_numbits.py b/tests/test_numbits.py
index 3f69b4de..f7032de7 100644
--- a/tests/test_numbits.py
+++ b/tests/test_numbits.py
@@ -115,9 +115,9 @@ class NumbitsSqliteFunctionTest(CoverageTest):
 
     def test_numbits_union(self):
         res = self.cursor.execute(
-            "select numbits_union("
-                "(select numbits from data where id = 7),"
-                "(select numbits from data where id = 9)"
+            "select numbits_union(" +
+                "(select numbits from data where id = 7)," +
+                "(select numbits from data where id = 9)" +
                 ")"
         )
         expected = [
@@ -129,9 +129,9 @@ class NumbitsSqliteFunctionTest(CoverageTest):
 
     def test_numbits_intersection(self):
         res = self.cursor.execute(
-            "select numbits_intersection("
-                "(select numbits from data where id = 7),"
-                "(select numbits from data where id = 9)"
+            "select numbits_intersection(" +
+                "(select numbits from data where id = 7)," +
+                "(select numbits from data where id = 9)" +
                 ")"
         )
         answer = numbits_to_nums(list(res)[0][0])
diff --git a/tests/test_oddball.py b/tests/test_oddball.py
index a97fc190..c3082abb 100644
--- a/tests/test_oddball.py
+++ b/tests/test_oddball.py
@@ -484,9 +484,9 @@ class GettraceTest(CoverageTest):
 
         out = self.stdout().replace(self.last_module_name, "coverage_test")
         expected = (
-            "call: coverage_test.py @ 12\n"
-            "line: coverage_test.py @ 13\n"
-            "line: coverage_test.py @ 14\n"
+            "call: coverage_test.py @ 12\n" +
+            "line: coverage_test.py @ 13\n" +
+            "line: coverage_test.py @ 14\n" +
             "return: coverage_test.py @ 14\n"
         )
         assert expected == out
diff --git a/tests/test_parser.py b/tests/test_parser.py
index 1b4e8aca..82bf7616 100644
--- a/tests/test_parser.py
+++ b/tests/test_parser.py
@@ -120,7 +120,7 @@ class PythonParserTest(CoverageTest):
 
     def test_indentation_error(self):
         msg = (
-            "Couldn't parse '<code>' as Python source: "
+            "Couldn't parse '<code>' as Python source: " +
             "'unindent does not match any outer indentation level' at line 3"
         )
         with pytest.raises(NotPython, match=msg):
diff --git a/tests/test_process.py b/tests/test_process.py
index c41c57b7..1adb6cff 100644
--- a/tests/test_process.py
+++ b/tests/test_process.py
@@ -130,7 +130,7 @@ class ProcessTest(CoverageTest):
         self.assert_exists(".coverage")
         self.assert_exists(".coverage.bad")
         warning_regex = (
-            r"CoverageWarning: Couldn't use data file '.*\.coverage\.bad': "
+            r"CoverageWarning: Couldn't use data file '.*\.coverage\.bad': " +
             r"file (is encrypted or )?is not a database"
         )
         assert re.search(warning_regex, out)
@@ -163,9 +163,8 @@ class ProcessTest(CoverageTest):
         for n in "12":
             self.assert_exists(f".coverage.bad{n}")
             warning_regex = (
-                r"CoverageWarning: Couldn't use data file '.*\.coverage.bad{}': "
+                fr"CoverageWarning: Couldn't use data file '.*\.coverage.bad{n}': " +
                 r"file (is encrypted or )?is not a database"
-                .format(n)
             )
             assert re.search(warning_regex, out)
         assert re.search(r"No usable data files", out)
@@ -725,9 +724,9 @@ class ProcessTest(CoverageTest):
         assert "Goodbye!" in out
 
         msg = (
-            "CoverageWarning: "
-            "Already imported a file that will be measured: {} "
-            "(already-imported)").format(goodbye_path)
+            f"CoverageWarning: Already imported a file that will be measured: {goodbye_path} " +
+            "(already-imported)"
+        )
         assert msg in out
 
     @pytest.mark.expensive
@@ -1313,10 +1312,10 @@ class UnicodeFilePathsTest(CoverageTest):
         assert ' name="h\xe2t.py"'.encode() in xml
 
         report_expected = (
-            "Name     Stmts   Miss  Cover\n"
-            "----------------------------\n"
-            "h\xe2t.py       1      0   100%\n"
-            "----------------------------\n"
+            "Name     Stmts   Miss  Cover\n" +
+            "----------------------------\n" +
+            "h\xe2t.py       1      0   100%\n" +
+            "----------------------------\n" +
             "TOTAL        1      0   100%\n"
         )
 
@@ -1357,12 +1356,12 @@ class UnicodeFilePathsTest(CoverageTest):
         }
 
         report_expected = (
-            "Name            Stmts   Miss  Cover\n"
-            "-----------------------------------\n"
-            "\xe2%saccented.py       1      0   100%%\n"
-            "-----------------------------------\n"
-            "TOTAL               1      0   100%%\n"
-        ) % os.sep
+            "Name            Stmts   Miss  Cover\n" +
+            "-----------------------------------\n" +
+            f"\xe2{os.sep}accented.py       1      0   100%\n" +
+            "-----------------------------------\n" +
+            "TOTAL               1      0   100%\n"
+        )
 
         out = self.run_command("coverage report")
         assert out == report_expected
diff --git a/tests/test_templite.py b/tests/test_templite.py
index e4d83647..0f86690b 100644
--- a/tests/test_templite.py
+++ b/tests/test_templite.py
@@ -148,7 +148,7 @@ class TempliteTest(CoverageTest):
 
     def test_multiple_loops(self):
         self.try_render(
-            "{% for n in nums %}{{n}}{% endfor %} and "
+            "{% for n in nums %}{{n}}{% endfor %} and " +
                                     "{% for n in nums %}{{n}}{% endfor %}",
             {'nums': [1,2,3]},
             "123 and 123"
@@ -201,10 +201,10 @@ class TempliteTest(CoverageTest):
                 return self.it
         obj = Complex(it={'x':"Hello", 'y': 0})
         self.try_render(
-            "@"
-            "{% if obj.getit.x %}X{% endif %}"
-            "{% if obj.getit.y %}Y{% endif %}"
-            "{% if obj.getit.y|str %}S{% endif %}"
+            "@" +
+            "{% if obj.getit.x %}X{% endif %}" +
+            "{% if obj.getit.y %}Y{% endif %}" +
+            "{% if obj.getit.y|str %}S{% endif %}" +
             "!",
             { 'obj': obj, 'str': str },
             "@XS!"
@@ -229,10 +229,10 @@ class TempliteTest(CoverageTest):
 
     def test_nested_loops(self):
         self.try_render(
-            "@"
-            "{% for n in nums %}"
-                "{% for a in abc %}{{a}}{{n}}{% endfor %}"
-            "{% endfor %}"
+            "@" +
+            "{% for n in nums %}" +
+                "{% for a in abc %}{{a}}{{n}}{% endfor %}" +
+            "{% endfor %}" +
             "!",
             {'nums': [0,1,2], 'abc': ['a', 'b', 'c']},
             "@a0b0c0a1b1c1a2b2c2!"
@@ -240,28 +240,28 @@ class TempliteTest(CoverageTest):
 
     def test_whitespace_handling(self):
         self.try_render(
-            "@{% for n in nums %}\n"
-            " {% for a in abc %}{{a}}{{n}}{% endfor %}\n"
+            "@{% for n in nums %}\n" +
+            " {% for a in abc %}{{a}}{{n}}{% endfor %}\n" +
             "{% endfor %}!\n",
             {'nums': [0, 1, 2], 'abc': ['a', 'b', 'c']},
             "@\n a0b0c0\n\n a1b1c1\n\n a2b2c2\n!\n"
             )
         self.try_render(
-            "@{% for n in nums -%}\n"
-            " {% for a in abc -%}\n"
-            "  {# this disappears completely -#}\n"
-            "  {{a-}}\n"
-            "  {{n -}}\n"
-            "  {{n    -}}\n"
-            " {% endfor %}\n"
+            "@{% for n in nums -%}\n" +
+            " {% for a in abc -%}\n" +
+            "  {# this disappears completely -#}\n" +
+            "  {{a-}}\n" +
+            "  {{n -}}\n" +
+            "  {{n    -}}\n" +
+            " {% endfor %}\n" +
             "{% endfor %}!\n",
             {'nums': [0, 1, 2], 'abc': ['a', 'b', 'c']},
             "@a00b00c00\na11b11c11\na22b22c22\n!\n"
             )
         self.try_render(
-            "@{% for n in nums -%}\n"
-            "  {{n -}}\n"
-            "  x\n"
+            "@{% for n in nums -%}\n" +
+            "  {{n -}}\n" +
+            "  x\n" +
             "{% endfor %}!\n",
             {'nums': [0, 1, 2]},
             "@0x\n1x\n2x\n!\n"
@@ -270,17 +270,17 @@ class TempliteTest(CoverageTest):
 
     def test_eat_whitespace(self):
         self.try_render(
-            "Hey!\n"
-            "{% joined %}\n"
-            "@{% for n in nums %}\n"
-            " {% for a in abc %}\n"
-            "  {# this disappears completely #}\n"
-            "  X\n"
-            "  Y\n"
-            "  {{a}}\n"
-            "  {{n }}\n"
-            " {% endfor %}\n"
-            "{% endfor %}!\n"
+            "Hey!\n" +
+            "{% joined %}\n" +
+            "@{% for n in nums %}\n" +
+            " {% for a in abc %}\n" +
+            "  {# this disappears completely #}\n" +
+            "  X\n" +
+            "  Y\n" +
+            "  {{a}}\n" +
+            "  {{n }}\n" +
+            " {% endfor %}\n" +
+            "{% endfor %}!\n" +
             "{% endjoined %}\n",
             {'nums': [0, 1, 2], 'abc': ['a', 'b', 'c']},
             "Hey!\n@XYa0XYb0XYc0XYa1XYb1XYc1XYa2XYb2XYc2!\n"
diff --git a/tests/test_testing.py b/tests/test_testing.py
index 4699799e..eae18890 100644
--- a/tests/test_testing.py
+++ b/tests/test_testing.py
@@ -61,20 +61,19 @@ class CoverageTestTest(CoverageTest):
         self.assert_file_count("afile.*", 1)
         self.assert_file_count("*.q", 0)
         msg = re.escape(
-            "There should be 13 files matching 'a*.txt', but there are these: "
+            "There should be 13 files matching 'a*.txt', but there are these: " +
             "['abcde.txt', 'afile.txt', 'axczz.txt']"
         )
         with pytest.raises(AssertionError, match=msg):
             self.assert_file_count("a*.txt", 13)
         msg = re.escape(
-            "There should be 12 files matching '*c*.txt', but there are these: "
+            "There should be 12 files matching '*c*.txt', but there are these: " +
             "['abcde.txt', 'axczz.txt']"
         )
         with pytest.raises(AssertionError, match=msg):
             self.assert_file_count("*c*.txt", 12)
         msg = re.escape(
-            "There should be 11 files matching 'afile.*', but there are these: "
-            "['afile.txt']"
+            "There should be 11 files matching 'afile.*', but there are these: ['afile.txt']"
         )
         with pytest.raises(AssertionError, match=msg):
             self.assert_file_count("afile.*", 11)
@@ -374,11 +373,11 @@ class ArczTest(CoverageTest):
         ([(-1, 1), (1, 2), (2, -5)], "(-1, 1) # .1\n(1, 2) # 12\n(2, -5) # 2-5\n"),
         ([(-26, 10), (12, 11), (18, 29), (35, -10), (1, 33), (100, 7)],
             (
-            "(-26, 10) # -QA\n"
-            "(12, 11) # CB\n"
-            "(18, 29) # IT\n"
-            "(35, -10) # Z-A\n"
-            "(1, 33) # 1X\n"
+            "(-26, 10) # -QA\n" +
+            "(12, 11) # CB\n" +
+            "(18, 29) # IT\n" +
+            "(35, -10) # Z-A\n" +
+            "(1, 33) # 1X\n" +
             "(100, 7) # ?7\n"
             )
         ),