response to review

cylc/flow/scripts/lint.py

@@ -31,8 +31,7 @@
 In-place mode ("-i, --inplace") writes suggestions into the file as comments.
 Commit to version control before using this, in case you want to back out.
 
-Configurations for Cylc lint can also be set in a pyproject.toml file. For
-example:
+Configurations for Cylc lint can also be set in a pyproject.toml file.
 
 """
 from colorama import Fore
@@ -46,6 +45,7 @@
 from cylc.flow.exceptions import CylcError
 from cylc.flow.option_parsers import (
     CylcOptionParser as COP,
+    WORKFLOW_ID_OR_PATH_ARG_DOC
 )
 from cylc.flow.cfgspec.workflow import upg, SPEC
 from cylc.flow.id_cli import parse_id
@@ -239,7 +239,10 @@ def get_pyproject_toml(dir_):
     tomlfile = Path(dir_ / 'pyproject.toml')
     tomldata = {}
     if tomlfile.is_file():
-        loadeddata = tomli.loads(tomlfile.read_text())
+        try:
+            loadeddata = tomli.loads(tomlfile.read_text())
+        except Exception as exc:  # noqa
+            raise CylcError('pyproject.toml did not load: ' + exc.args[0])
         if 'cylc-lint' in loadeddata:
             for key in keys:
                 tomldata[key] = loadeddata.get('cylc-lint').get(key, [])
@@ -386,7 +389,7 @@ def get_upgrader_info():
 }
 
 
-def parse_checks(check_args, ignores=None, max_line_len=None):
+def parse_checks(check_args, ignores=None, max_line_len=130, reference=False):
     """Collapse metadata in checks dicts.
 
     Args:
@@ -411,11 +414,19 @@ def parse_checks(check_args, ignores=None, max_line_len=None):
                     meta.update({'index': index})
                 if f'{purpose}{index:03d}' not in ignores:
                     parsedchecks.update({pattern: meta})
-            # Add max line length check.
-            if 'S' in purpose and max_line_len:
+            if 'S' in purpose:
+                if not max_line_len:
+                    max_line_len = 130
                 regex = r"^.{" + str(max_line_len) + r"}"
+                if reference:
+                    msg = (
+                        'line > {max_line_len} characters. Max line length '
+                        'set in pyproject.toml (default 130)'
+                    )
+                else:
+                    msg = f'line > {max_line_len} characters.'
                 parsedchecks[re.compile(regex)] = {
-                    'short': f'line > {max_line_len} characters.',
+                    'short': msg,
                     'url': STYLE_GUIDE + 'line-length-and-continuation',
                     'index': 8,
                     'purpose': 'S'
@@ -565,7 +576,7 @@ def get_reference_text(checks):
 def get_option_parser() -> COP:
     parser = COP(
         COP_DOC,
-        argdoc=[COP.optional(('WORKFLOW | PATH ...', 'Workflows to lint'))],
+        argdoc=[COP.optional(WORKFLOW_ID_OR_PATH_ARG_DOC)],
     )
     parser.add_option(
         '--inplace', '-i',
@@ -617,7 +628,7 @@ def main(parser: COP, options: 'Values', *targets) -> None:
             rulesets = ['728', 'style']
         else:
             rulesets = [options.linter]
-        print(get_reference_text(parse_checks(rulesets)))
+        print(get_reference_text(parse_checks(rulesets, reference=True)))
         exit(0)
 
     # If target not given assume we are looking at PWD
@@ -710,4 +721,4 @@ def main(parser: COP, options: 'Values', *targets) -> None:
 
 # NOTE: use += so that this works with __import__
 # (docstring needed for `cylc help all` output)
-__doc__ += get_reference_rst(parse_checks(['728', 'style']))
+__doc__ += get_reference_rst(parse_checks(['728', 'style'], reference=True))

tests/functional/cylc-lint/00.lint.t

@@ -29,7 +29,7 @@ __HERE__
 rm etc/global.cylc
 
 TEST_NAME="${TEST_NAME_BASE}.vanilla"
-run_ok "${TEST_NAME}" cylc lint
+run_ok "${TEST_NAME}" cylc lint .
 named_grep_ok "check-for-error-code" "S004" "${TEST_NAME}.stdout"
 
 TEST_NAME="${TEST_NAME_BASE}.pick-a-ruleset"

tests/unit/scripts/test_lint.py

@@ -472,3 +472,26 @@ def test_validate_toml_items(input_, error):
 def test_merge_cli_with_tomldata(clidata, tomldata, expect):
     """It merges each of the three sections correctly: see function.__doc__"""
     assert merge_cli_with_tomldata(clidata, tomldata) == expect
+
+
+def test_invalid_tomlfile(tmp_path):
+    """It fails nicely if pyproject.toml is malformed"""
+    tomlfile = (tmp_path / 'pyproject.toml')
+    tomlfile.write_text('foo :{}')
+    expected_msg = 'pyproject.toml did not load:'
+    with pytest.raises(CylcError, match=expected_msg):
+        get_pyproject_toml(tmp_path)
+
+
+@pytest.mark.parametrize(
+    'ref, expect',
+    [
+        [True, 'line > {max_line_len} characters'],
+        [False, 'line > 130 characters']
+    ]
+)
+def test_parse_checks_reference_mode(ref, expect):
+    result = parse_checks(['style'], reference=ref)
+    key = [i for i in result.keys()][-1]
+    value = result[key]
+    assert expect in value['short']