Standalone comments inside nested bracketed expressions block the expression from wrapping

[njsmith]

This is... not what I expected black to do :-)

     # Capture each of the exceptions in the MultiError along with each of their causes and contexts
     if isinstance(exc_value, MultiError):
         embedded = []
         for exc in exc_value.exceptions:
             if exc not in _seen:
                 embedded.append(
-                    traceback.TracebackException.from_exception(
-                        exc,
-                        limit=limit,
-                        lookup_lines=lookup_lines,
-                        capture_locals=capture_locals,
-                        # copy the set of _seen exceptions so that duplicates
-                        # shared between sub-exceptions are not omitted
-                        _seen=set(_seen)
-                    )
+                    traceback.TracebackException.from_exception(exc, limit=limit, lookup_lines=lookup_lines, capture_locals=capture_locals, _seen=set(_seen))
+                    # copy the set of _seen exceptions so that duplicates
+                    # shared between sub-exceptions are not omitted
                 )

[dstufft]

I believe I am also experiencing this, which ends up with a 3000+ length line for me:

@@ -749,183 +667,19 @@ class TestFileUpload:

     @pytest.mark.parametrize(
         ("post_data", "message"),
-        [
-            # metadata_version errors.
-            (
-                {},
-                "None is an invalid value for Metadata-Version. "
-                "Error: This field is required. "
-                "see "
-                "https://packaging.python.org/specifications/core-metadata",
-            ),
-            (
-                {"metadata_version": "-1"},
-                "'-1' is an invalid value for Metadata-Version. "
-                "Error: Unknown Metadata Version "
-                "see "
-                "https://packaging.python.org/specifications/core-metadata",
-            ),
-
-            # name errors.
-            (
-                {"metadata_version": "1.2"},
-                "'' is an invalid value for Name. "
-                "Error: This field is required. "
-                "see "
-                "https://packaging.python.org/specifications/core-metadata",
-            ),
-            (
-                {"metadata_version": "1.2", "name": "foo-"},
-                "'foo-' is an invalid value for Name. "
-                "Error: Must start and end with a letter or numeral and "
-                "contain only ascii numeric and '.', '_' and '-'. "
-                "see "
-                "https://packaging.python.org/specifications/core-metadata",
-            ),
-
-            # version errors.
-            (
-                {"metadata_version": "1.2", "name": "example"},
-                "'' is an invalid value for Version. "
-                "Error: This field is required. "
-                "see "
-                "https://packaging.python.org/specifications/core-metadata",
-            ),
-            (
-                {
-                    "metadata_version": "1.2",
-                    "name": "example",
-                    "version": "dog",
-                },
-                "'dog' is an invalid value for Version. "
-                "Error: Must start and end with a letter or numeral and "
-                "contain only ascii numeric and '.', '_' and '-'. "
-                "see "
-                "https://packaging.python.org/specifications/core-metadata",
-            ),
-
-            # filetype/pyversion errors.
-            (
-                {
-                    "metadata_version": "1.2",
-                    "name": "example",
-                    "version": "1.0",
-                    "md5_digest": "bad",
-                },
-                "filetype: This field is required.",
-            ),
-            (
-                {
-                    "metadata_version": "1.2",
-                    "name": "example",
-                    "version": "1.0",
-                    "filetype": "bdist_wat",
-                },
-                "Error: Python version is required for binary distribution "
-                "uploads."
-            ),
-            (
-                {
-                    "metadata_version": "1.2",
-                    "name": "example",
-                    "version": "1.0",
-                    "filetype": "bdist_wat",
-                    "pyversion": "1.0",
-                    "md5_digest": "bad",
-                },
-                "filetype: Unknown type of file.",
-            ),
-            (
-                {
-                    "metadata_version": "1.2",
-                    "name": "example",
-                    "version": "1.0",
-                    "filetype": "sdist",
-                    "pyversion": "1.0",
-                },
-                "Error: The only valid Python version for a sdist is "
-                "'source'."
-            ),
-
-            # digest errors.
-            (
-                {
-                    "metadata_version": "1.2",
-                    "name": "example",
-                    "version": "1.0",
-                    "filetype": "sdist",
-                },
-                "Error: Must include at least one message digest."
-            ),
-            (
-                {
-                    "metadata_version": "1.2",
-                    "name": "example",
-                    "version": "1.0",
-                    "filetype": "sdist",
-                    "sha256_digest": "an invalid sha256 digest",
-                },
-                "sha256_digest: "
-                "Must be a valid, hex encoded, SHA256 message digest."
-            ),
-
-            # summary errors
-            (
-                {
-                    "metadata_version": "1.2",
-                    "name": "example",
-                    "version": "1.0",
-                    "filetype": "sdist",
-                    "md5_digest": "a fake md5 digest",
-                    "summary": "A" * 513,
-                },
-                "'" + "A" * 513 + "' is an invalid value for Summary. "
-                "Error: Field cannot be longer than 512 characters. "
-                "see "
-                "https://packaging.python.org/specifications/core-metadata",
-            ),
-            (
-                {
-                    "metadata_version": "1.2",
-                    "name": "example",
-                    "version": "1.0",
-                    "filetype": "sdist",
-                    "md5_digest": "a fake md5 digest",
-                    "summary": "A\nB",
-                },
-                ("{!r} is an invalid value for Summary. ".format('A\nB') +
-                 "Error: Multiple lines are not allowed. "
-                 "see "
-                 "https://packaging.python.org/specifications/core-metadata"),
-            ),
-
-            # classifiers are a FieldStorage
-            (
-                {
-                    "metadata_version": "1.2",
-                    "name": "example",
-                    "version": "1.0",
-                    "filetype": "sdist",
-                    "classifiers": FieldStorage(),
-                },
-                "classifiers: Should not be a tuple.",
-            ),
-
-            # keywords are a FieldStorage
-            (
-                {
-                    "metadata_version": "1.2",
-                    "name": "example",
-                    "version": "1.0",
-                    "filetype": "sdist",
-                    "keywords": FieldStorage(),
-                },
-                "keywords: Should not be a tuple.",
-            ),
-        ],
+        [({}, "None is an invalid value for Metadata-Version. " "Error: This field is required. " "see " "https://packaging.python.org/specifications/core-metadata"), ({"metadata_version": "-1"}, "'-1' is an invalid value for Metadata-Version. " "Error: Unknown Metadata Version " "see " "https://packaging.python.org/specifications/core-metadata"), ({"metadata_version": "1.2"}, "'' is an invalid value for Name. " "Error: This field is required. " "see " "https://packaging.python.org/specifications/core-metadata"), ({"metadata_version": "1.2", "name": "foo-"}, "'foo-' is an invalid value for Name. " "Error: Must start and end with a letter or numeral and " "contain only ascii numeric and '.', '_' and '-'. " "see " "https://packaging.python.org/specifications/core-metadata"), ({"metadata_version": "1.2", "name": "example"}, "'' is an invalid value for Version. " "Error: This field is required. " "see " "https://packaging.python.org/specifications/core-metadata"), ({"metadata_version": "1.2", "name": "example", "version": "dog"}, "'dog' is an invalid value for Version. " "Error: Must start and end with a letter or numeral and " "contain only ascii numeric and '.', '_' and '-'. " "see " "https://packaging.python.org/specifications/core-metadata"), ({"metadata_version": "1.2", "name": "example", "version": "1.0", "md5_digest": "bad"}, "filetype: This field is required."), ({"metadata_version": "1.2", "name": "example", "version": "1.0", "filetype": "bdist_wat"}, "Error: Python version is required for binary distribution " "uploads."), ({"metadata_version": "1.2", "name": "example", "version": "1.0", "filetype": "bdist_wat", "pyversion": "1.0", "md5_digest": "bad"}, "filetype: Unknown type of file."), ({"metadata_version": "1.2", "name": "example", "version": "1.0", "filetype": "sdist", "pyversion": "1.0"}, "Error: The only valid Python version for a sdist is " "'source'."), ({"metadata_version": "1.2", "name": "example", "version": "1.0", "filetype": "sdist"}, "Error: Must include at least one message digest."), ({"metadata_version": "1.2", "name": "example", "version": "1.0", "filetype": "sdist", "sha256_digest": "an invalid sha256 digest"}, "sha256_digest: " "Must be a valid, hex encoded, SHA256 message digest."), ({"metadata_version": "1.2", "name": "example", "version": "1.0", "filetype": "sdist", "md5_digest": "a fake md5 digest", "summary": "A" * 513}, "'" + "A" * 513 + "' is an invalid value for Summary. " "Error: Field cannot be longer than 512 characters. " "see " "https://packaging.python.org/specifications/core-metadata"), ({"metadata_version": "1.2", "name": "example", "version": "1.0", "filetype": "sdist", "md5_digest": "a fake md5 digest", "summary": "A\nB"}, ("{!r} is an invalid value for Summary. ".format('A\nB') + "Error: Multiple lines are not allowed. " "see " "https://packaging.python.org/specifications/core-metadata")), ({"metadata_version": "1.2", "name": "example", "version": "1.0", "filetype": "sdist", "classifiers": FieldStorage()}, "classifiers: Should not be a tuple."), ({"metadata_version": "1.2", "name": "example", "version": "1.0", "filetype": "sdist", "keywords": FieldStorage()}, "keywords: Should not be a tuple.")],
+        # metadata_version errors.
+        # name errors.
+        # version errors.
+        # filetype/pyversion errors.
+        # digest errors.
+        # summary errors
+        # classifiers are a FieldStorage
+        # keywords are a FieldStorage
     )
-    def test_fails_invalid_post_data(self, pyramid_config, db_request,
-                                     post_data, message):
+    def test_fails_invalid_post_data(
+        self, pyramid_config, db_request, post_data, message
+    ):
         pyramid_config.testing_securitypolicy(userid=1)
         db_request.POST = MultiDict(post_data)

[wbolster]

Another example of this with long SQLAlchemy queries containing some inline comments in long chained calls like x.filter().order_by().all():

def foo(list_a, list_b):
    results = (
        User.query
        .filter(User.foo == 'bar')  # Because foo.
        .filter(db.or_(
            User.field_a.astext.in_(list_a),
            User.field_b.astext.in_(list_b),
        ))
        .filter(User.xyz.is_(None))
        # Another comment about the filtering on is_quux goes here.
        .filter(db.not_(
            User.is_pending.astext.cast(db.Boolean).is_(True)))
        .order_by(User.created_at.desc())
        .with_for_update(key_share=True)
        .all())
    return results

becomes

def foo(list_a, list_b):
    results = (
        User.query.filter(User.foo == 'bar').filter(db.or_(User.field_a.astext.in_(list_a), User.field_b.astext.in_(list_b))).filter(User.xyz.is_(None)).filter(db.not_(User.is_pending.astext.cast(db.Boolean).is_(True))).order_by(User.created_at.desc()).with_for_update(key_share=True).all()  # Because foo.
        # Another comment about the filtering on is_quux goes here.
    )
    return results

This produces extremely long lines, and moves the comments around to the wrong places.

[ambv]

@wbolster, Black will not support the "fluent interfaces" indentation style that you're employing in your SQLAlchemy queries. Your example is reformatted like this:

def foo(list_a, list_b):
    results = (
        User.query.filter(User.foo == 'bar').filter(  # Because foo.
            db.or_(User.field_a.astext.in_(list_a), User.field_b.astext.in_(list_b))
        ).filter(
            User.xyz.is_(None)
        )
        # Another comment about the filtering on is_quux goes here.
        .filter(db.not_(User.is_pending.astext.cast(db.Boolean).is_(True))).order_by(
            User.created_at.desc()
        ).with_for_update(
            key_share=True
        ).all()
    )
    return results

See #67 for more reference.

[dstufft]

Damn, I find the fluent interfaces way nicer for SQLAlchemy queries :) ah well.