From c9ed44aafa8561a0774fb570dd04cf76064842a7 Mon Sep 17 00:00:00 2001
From: drinob <drinob@gmail.com>
Date: Mon, 12 Oct 2020 09:37:59 +0300
Subject: [PATCH 01/24] Added kw_only support for py2

---
 src/attr/_make.py  | 25 ++++++++++++++++++------
 tests/test_make.py | 47 +++++++++++++++++-----------------------------
 2 files changed, 36 insertions(+), 36 deletions(-)

diff --git a/src/attr/_make.py b/src/attr/_make.py
index 4c9e074f8..4b34642dd 100644
--- a/src/attr/_make.py
+++ b/src/attr/_make.py
@@ -2159,14 +2159,27 @@ def fmt_setter_with_converter(
     args = ", ".join(args)
     if kw_only_args:
         if PY2:
-            raise PythonTooOldError(
-                "Keyword-only arguments only work on Python 3 and later."
+            kw_only_args.sort(key=lambda arg: "=" in arg)
+            kw_only_arg_tuple = ", ".join(
+                arg.split("=", 1)[0] for arg in kw_only_args
             )
 
-        args += "{leading_comma}*, {kw_only_args}".format(
-            leading_comma=", " if args else "",
-            kw_only_args=", ".join(kw_only_args),
-        )
+            parse_kw_only_args_lines = [
+                "def __attrs_unpack_kw_only__(%s):" % ", ".join(kw_only_args),
+                "    return %s" % kw_only_arg_tuple,
+                "%s = __attrs_unpack_kw_only__(**_kwargs)" % kw_only_arg_tuple,
+                "    ",
+            ]
+            lines = parse_kw_only_args_lines + lines
+
+            args += "{leading_comma} **_kwargs".format(
+                leading_comma=", " if args else ""
+            )
+        else:
+            args += "{leading_comma}*, {kw_only_args}".format(
+                leading_comma=", " if args else "",
+                kw_only_args=", ".join(kw_only_args),
+            )
     return (
         """\
 def __init__(self, {args}):
diff --git a/tests/test_make.py b/tests/test_make.py
index d3f4a279e..47d0cc323 100644
--- a/tests/test_make.py
+++ b/tests/test_make.py
@@ -712,7 +712,6 @@ class SubClass(BaseClass):
         assert hash(ba) == hash(sa)
 
 
-@pytest.mark.skipif(PY2, reason="keyword-only arguments are PY3-only.")
 class TestKeywordOnlyAttributes(object):
     """
     Tests for keyword-only attributes.
@@ -724,7 +723,7 @@ def test_adds_keyword_only_arguments(self):
         """
 
         @attr.s
-        class C:
+        class C(object):
             a = attr.ib()
             b = attr.ib(default=2, kw_only=True)
             c = attr.ib(kw_only=True)
@@ -743,7 +742,7 @@ def test_ignores_kw_only_when_init_is_false(self):
         """
 
         @attr.s
-        class C:
+        class C(object):
             x = attr.ib(init=False, default=0, kw_only=True)
             y = attr.ib()
 
@@ -759,15 +758,20 @@ def test_keyword_only_attributes_presence(self):
         """
 
         @attr.s
-        class C:
+        class C(object):
             x = attr.ib(kw_only=True)
 
         with pytest.raises(TypeError) as e:
             C()
 
-        assert (
-            "missing 1 required keyword-only argument: 'x'"
-        ) in e.value.args[0]
+        if PY2:
+            assert (
+                "__attrs_unpack_kw_only__() takes exactly 1 argument (0 given)"
+            ) in e.value.args[0]
+        else:
+            assert (
+                "missing 1 required keyword-only argument: 'x'"
+            ) in e.value.args[0]
 
     def test_keyword_only_attributes_can_come_in_any_order(self):
         """
@@ -778,7 +782,7 @@ def test_keyword_only_attributes_can_come_in_any_order(self):
         """
 
         @attr.s
-        class C:
+        class C(object):
             a = attr.ib(kw_only=True)
             b = attr.ib(kw_only=True, default="b")
             c = attr.ib(kw_only=True)
@@ -807,7 +811,7 @@ def test_keyword_only_attributes_allow_subclassing(self):
         """
 
         @attr.s
-        class Base:
+        class Base(object):
             x = attr.ib(default=0)
 
         @attr.s
@@ -826,7 +830,7 @@ def test_keyword_only_class_level(self):
         """
 
         @attr.s(kw_only=True)
-        class C:
+        class C(object):
             x = attr.ib()
             y = attr.ib(kw_only=True)
 
@@ -845,7 +849,7 @@ def test_keyword_only_class_level_subclassing(self):
         """
 
         @attr.s
-        class Base:
+        class Base(object):
             x = attr.ib(default=0)
 
         @attr.s(kw_only=True)
@@ -868,7 +872,7 @@ def test_init_false_attribute_after_keyword_attribute(self):
         """
 
         @attr.s
-        class KwArgBeforeInitFalse:
+        class KwArgBeforeInitFalse(object):
             kwarg = attr.ib(kw_only=True)
             non_init_function_default = attr.ib(init=False)
             non_init_keyword_default = attr.ib(
@@ -896,7 +900,7 @@ def test_init_false_attribute_after_keyword_attribute_with_inheritance(
         """
 
         @attr.s
-        class KwArgBeforeInitFalseParent:
+        class KwArgBeforeInitFalseParent(object):
             kwarg = attr.ib(kw_only=True)
 
         @attr.s
@@ -923,23 +927,6 @@ class TestKeywordOnlyAttributesOnPy2(object):
     Tests for keyword-only attribute behavior on py2.
     """
 
-    def test_syntax_error(self):
-        """
-        Keyword-only attributes raise Syntax error on ``__init__`` generation.
-        """
-
-        with pytest.raises(PythonTooOldError):
-
-            @attr.s(kw_only=True)
-            class ClassLevel(object):
-                a = attr.ib()
-
-        with pytest.raises(PythonTooOldError):
-
-            @attr.s()
-            class AttrLevel(object):
-                a = attr.ib(kw_only=True)
-
     def test_no_init(self):
         """
         Keyworld-only is a no-op, not any error, if ``init=false``.

From c938678ab1dd47a8a34ee731d21487710b5ae07c Mon Sep 17 00:00:00 2001
From: drinob <drinob@gmail.com>
Date: Mon, 12 Oct 2020 10:33:00 +0300
Subject: [PATCH 02/24] Docs update

---
 docs/examples.rst | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/docs/examples.rst b/docs/examples.rst
index 508aa9f6e..b4023bf36 100644
--- a/docs/examples.rst
+++ b/docs/examples.rst
@@ -146,7 +146,7 @@ On Python 3 it overrides the implicit detection.
 Keyword-only Attributes
 ~~~~~~~~~~~~~~~~~~~~~~~
 
-When using ``attrs`` on Python 3, you can also add `keyword-only <https://docs.python.org/3/glossary.html#keyword-only-parameter>`_ attributes:
+You can also add `keyword-only <https://docs.python.org/3/glossary.html#keyword-only-parameter>`_ attributes:
 
 .. doctest::
 
@@ -160,6 +160,8 @@ When using ``attrs`` on Python 3, you can also add `keyword-only <https://docs.p
     >>> A(a=1)
     A(a=1)
 
+``attrs`` supports ``kw_only`` attributes even on Python 2, though error messages are default python error messages and may be a bit confusing.
+
 ``kw_only`` may also be specified at via ``attr.s``, and will apply to all attributes:
 
 .. doctest::

From ca337e9628db28769f7d2aa9b873025987d82fb5 Mon Sep 17 00:00:00 2001
From: drinob <drinob@gmail.com>
Date: Thu, 15 Oct 2020 11:31:37 +0300
Subject: [PATCH 03/24] Added changelog

---
 changelog.d/700.changing.rst | 1 +
 1 file changed, 1 insertion(+)
 create mode 100644 changelog.d/700.changing.rst

diff --git a/changelog.d/700.changing.rst b/changelog.d/700.changing.rst
new file mode 100644
index 000000000..292a4d8d9
--- /dev/null
+++ b/changelog.d/700.changing.rst
@@ -0,0 +1 @@
+Added support for `kw_only=True` on Python 2.

From f636e147c09ec7684ac702ade0a8c97195f348e0 Mon Sep 17 00:00:00 2001
From: drinob <drinob@gmail.com>
Date: Thu, 15 Oct 2020 11:32:34 +0300
Subject: [PATCH 04/24] Better exception message, moved code to function

---
 src/attr/_make.py  | 48 +++++++++++++++++++++++++++++-----------------
 tests/test_make.py |  2 +-
 2 files changed, 31 insertions(+), 19 deletions(-)

diff --git a/src/attr/_make.py b/src/attr/_make.py
index 4b34642dd..9939705d0 100644
--- a/src/attr/_make.py
+++ b/src/attr/_make.py
@@ -1905,6 +1905,31 @@ def _assign_with_converter(attr_name, value_var, has_on_setattr):
     )
 
 
+def _unpack_kw_only_py2(attr_name, default=None):
+    """
+    Unpack *attr_name* for _kw_only dict. Used to support kw_only arguments in py2.
+    """
+    if default is not None:
+        arg_default = ", %s" % default
+    else:
+        arg_default = ""
+    return "%s = _kw_only.pop('%s'%s)" % (attr_name, attr_name, arg_default)
+
+
+def _unpack_kw_only_lines_py2(kw_only_args):
+    lines = ["try:"]
+    lines += [
+        "    " + _unpack_kw_only_py2(*arg.split("=")) for arg in kw_only_args
+    ]
+    lines += [
+        "except KeyError as _key_error:",
+        "    raise TypeError('__init__() missing required keyword-only argument: %s' % _key_error)",
+        "if _kw_only:",
+        "    raise TypeError('__init__() got an unexpected keyword argument %r' % next(iter(_kw_only)))",
+    ]
+    return lines
+
+
 def _attrs_to_init_script(
     attrs,
     frozen,
@@ -2159,26 +2184,13 @@ def fmt_setter_with_converter(
     args = ", ".join(args)
     if kw_only_args:
         if PY2:
-            kw_only_args.sort(key=lambda arg: "=" in arg)
-            kw_only_arg_tuple = ", ".join(
-                arg.split("=", 1)[0] for arg in kw_only_args
-            )
+            lines = _unpack_kw_only_lines_py2(kw_only_args) + lines
 
-            parse_kw_only_args_lines = [
-                "def __attrs_unpack_kw_only__(%s):" % ", ".join(kw_only_args),
-                "    return %s" % kw_only_arg_tuple,
-                "%s = __attrs_unpack_kw_only__(**_kwargs)" % kw_only_arg_tuple,
-                "    ",
-            ]
-            lines = parse_kw_only_args_lines + lines
-
-            args += "{leading_comma} **_kwargs".format(
-                leading_comma=", " if args else ""
-            )
+            args += "%s**_kw_only" % (", " if args else "",)  # leading comma
         else:
-            args += "{leading_comma}*, {kw_only_args}".format(
-                leading_comma=", " if args else "",
-                kw_only_args=", ".join(kw_only_args),
+            args += "%s*, %s" % (
+                ", " if args else "",  # leading comma
+                ", ".join(kw_only_args),  # kw_only args
             )
     return (
         """\
diff --git a/tests/test_make.py b/tests/test_make.py
index 47d0cc323..5fe79eefc 100644
--- a/tests/test_make.py
+++ b/tests/test_make.py
@@ -766,7 +766,7 @@ class C(object):
 
         if PY2:
             assert (
-                "__attrs_unpack_kw_only__() takes exactly 1 argument (0 given)"
+                "missing required keyword-only argument: 'x'"
             ) in e.value.args[0]
         else:
             assert (

From e12ad7549e3871cb5797cb714bb5c79cddd8c707 Mon Sep 17 00:00:00 2001
From: drinob <drinob@gmail.com>
Date: Thu, 15 Oct 2020 11:40:15 +0300
Subject: [PATCH 05/24] Moved py2-only functions under if PY2:

---
 src/attr/_make.py | 48 ++++++++++++++++++++++++++---------------------
 1 file changed, 27 insertions(+), 21 deletions(-)

diff --git a/src/attr/_make.py b/src/attr/_make.py
index 9939705d0..d4bc2c479 100644
--- a/src/attr/_make.py
+++ b/src/attr/_make.py
@@ -1905,29 +1905,35 @@ def _assign_with_converter(attr_name, value_var, has_on_setattr):
     )
 
 
-def _unpack_kw_only_py2(attr_name, default=None):
-    """
-    Unpack *attr_name* for _kw_only dict. Used to support kw_only arguments in py2.
-    """
-    if default is not None:
-        arg_default = ", %s" % default
-    else:
-        arg_default = ""
-    return "%s = _kw_only.pop('%s'%s)" % (attr_name, attr_name, arg_default)
+if PY2:
 
+    def _unpack_kw_only_py2(attr_name, default=None):
+        """
+        Unpack *attr_name* for _kw_only dict. Used to support kw_only arguments in py2.
+        """
+        if default is not None:
+            arg_default = ", %s" % default
+        else:
+            arg_default = ""
+        return "%s = _kw_only.pop('%s'%s)" % (
+            attr_name,
+            attr_name,
+            arg_default,
+        )
 
-def _unpack_kw_only_lines_py2(kw_only_args):
-    lines = ["try:"]
-    lines += [
-        "    " + _unpack_kw_only_py2(*arg.split("=")) for arg in kw_only_args
-    ]
-    lines += [
-        "except KeyError as _key_error:",
-        "    raise TypeError('__init__() missing required keyword-only argument: %s' % _key_error)",
-        "if _kw_only:",
-        "    raise TypeError('__init__() got an unexpected keyword argument %r' % next(iter(_kw_only)))",
-    ]
-    return lines
+    def _unpack_kw_only_lines_py2(kw_only_args):
+        lines = ["try:"]
+        lines += [
+            "    " + _unpack_kw_only_py2(*arg.split("="))
+            for arg in kw_only_args
+        ]
+        lines += [
+            "except KeyError as _key_error:",
+            "    raise TypeError('__init__() missing required keyword-only argument: %s' % _key_error)",
+            "if _kw_only:",
+            "    raise TypeError('__init__() got an unexpected keyword argument %r' % next(iter(_kw_only)))",
+        ]
+        return lines
 
 
 def _attrs_to_init_script(

From c6e58aa066b9eb175cde254497ce4c50c062174e Mon Sep 17 00:00:00 2001
From: drinob <drinob@gmail.com>
Date: Thu, 15 Oct 2020 11:50:57 +0300
Subject: [PATCH 06/24] Tested fancy error message for unexpected kw-only
 argument

---
 tests/test_make.py | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/tests/test_make.py b/tests/test_make.py
index 5fe79eefc..c78af7203 100644
--- a/tests/test_make.py
+++ b/tests/test_make.py
@@ -773,6 +773,23 @@ class C(object):
                 "missing 1 required keyword-only argument: 'x'"
             ) in e.value.args[0]
 
+    def test_keyword_only_attributes_unexpected(self):
+        """
+        Raises `TypeError` when unexpected keyword argument passed.
+        """
+
+        @attr.s
+        class C(object):
+            x = attr.ib(kw_only=True)
+
+        with pytest.raises(TypeError) as e:
+            C(x=5, y=10)
+
+        assert(
+            "got an unexpected keyword argument 'y'"
+        ) in e.value.args[0]
+
+
     def test_keyword_only_attributes_can_come_in_any_order(self):
         """
         Mandatory vs non-mandatory attr order only matters when they are part

From 0a453404bbc0e9e4571673412eaa187ca96d6e02 Mon Sep 17 00:00:00 2001
From: drinob <drinob@gmail.com>
Date: Thu, 15 Oct 2020 11:55:10 +0300
Subject: [PATCH 07/24] Tested fancy error message for unexpected kw-only
 argument

---
 tests/test_make.py | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/tests/test_make.py b/tests/test_make.py
index c78af7203..fb6148777 100644
--- a/tests/test_make.py
+++ b/tests/test_make.py
@@ -785,10 +785,7 @@ class C(object):
         with pytest.raises(TypeError) as e:
             C(x=5, y=10)
 
-        assert(
-            "got an unexpected keyword argument 'y'"
-        ) in e.value.args[0]
-
+        assert ("got an unexpected keyword argument 'y'") in e.value.args[0]
 
     def test_keyword_only_attributes_can_come_in_any_order(self):
         """

From d052808a650fa4d29ec1d3f8c719285e411a4443 Mon Sep 17 00:00:00 2001
From: drinob <drinob@gmail.com>
Date: Thu, 15 Oct 2020 12:00:13 +0300
Subject: [PATCH 08/24] Fixed line length

---
 src/attr/_make.py | 58 +++++++++++++++++++++++++----------------------
 1 file changed, 31 insertions(+), 27 deletions(-)

diff --git a/src/attr/_make.py b/src/attr/_make.py
index d4bc2c479..12ca15312 100644
--- a/src/attr/_make.py
+++ b/src/attr/_make.py
@@ -1905,35 +1905,39 @@ def _assign_with_converter(attr_name, value_var, has_on_setattr):
     )
 
 
-if PY2:
+def _unpack_kw_only_py2(attr_name, default=None):
+    """
+    Unpack *attr_name* from _kw_only dict.
+    """
+    if default is not None:
+        arg_default = ", %s" % default
+    else:
+        arg_default = ""
+    return "%s = _kw_only.pop('%s'%s)" % (
+        attr_name,
+        attr_name,
+        arg_default,
+    )
 
-    def _unpack_kw_only_py2(attr_name, default=None):
-        """
-        Unpack *attr_name* for _kw_only dict. Used to support kw_only arguments in py2.
-        """
-        if default is not None:
-            arg_default = ", %s" % default
-        else:
-            arg_default = ""
-        return "%s = _kw_only.pop('%s'%s)" % (
-            attr_name,
-            attr_name,
-            arg_default,
-        )
 
-    def _unpack_kw_only_lines_py2(kw_only_args):
-        lines = ["try:"]
-        lines += [
-            "    " + _unpack_kw_only_py2(*arg.split("="))
-            for arg in kw_only_args
-        ]
-        lines += [
-            "except KeyError as _key_error:",
-            "    raise TypeError('__init__() missing required keyword-only argument: %s' % _key_error)",
-            "if _kw_only:",
-            "    raise TypeError('__init__() got an unexpected keyword argument %r' % next(iter(_kw_only)))",
-        ]
-        return lines
+def _unpack_kw_only_lines_py2(kw_only_args):
+    """
+    Unpack all *kw_only_args* from _kw_only dict and handle errors.
+    """
+    lines = ["try:"]
+    lines += [
+        "    " + _unpack_kw_only_py2(*arg.split("="))
+        for arg in kw_only_args
+    ]
+    lines += """\
+except KeyError as _key_error:
+    _msg = '__init__() missing required keyword-only argument: %s'
+    raise TypeError(_msg % _key_error)
+if _kw_only:
+    _msg = '__init__() got an unexpected keyword argument %r'
+    raise TypeError(_msg % next(iter(_kw_only)))
+""".split('\n')
+    return lines
 
 
 def _attrs_to_init_script(

From 356a25603970f9f1285b590d9addb550d2c4945e Mon Sep 17 00:00:00 2001
From: drinob <drinob@gmail.com>
Date: Thu, 15 Oct 2020 12:03:11 +0300
Subject: [PATCH 09/24] Added versionchanged

---
 src/attr/_make.py | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/attr/_make.py b/src/attr/_make.py
index 12ca15312..e3a636e40 100644
--- a/src/attr/_make.py
+++ b/src/attr/_make.py
@@ -223,6 +223,7 @@ def attrib(
     .. deprecated:: 19.2.0 *cmp* Removal on or after 2021-06-01.
     .. versionadded:: 19.2.0 *eq* and *order*
     .. versionadded:: 20.1.0 *on_setattr*
+    .. versionchanged:: 20.3.0 *kw_only* supported on python 2
     """
     eq, order = _determine_eq_order(cmp, eq, order, True)
 

From 430ea7324c29aa4518057ee81f8a154953f6eadb Mon Sep 17 00:00:00 2001
From: drinob <drinob@gmail.com>
Date: Thu, 15 Oct 2020 12:10:45 +0300
Subject: [PATCH 10/24] Updated docs

---
 docs/examples.rst | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/docs/examples.rst b/docs/examples.rst
index b4023bf36..8497734fc 100644
--- a/docs/examples.rst
+++ b/docs/examples.rst
@@ -146,7 +146,7 @@ On Python 3 it overrides the implicit detection.
 Keyword-only Attributes
 ~~~~~~~~~~~~~~~~~~~~~~~
 
-You can also add `keyword-only <https://docs.python.org/3/glossary.html#keyword-only-parameter>`_ attributes:
+You can also add `keyword-only <https://docs.python.org/3/glossary.html#keyword-only-parameter>`_ attributes (even on Python 2):
 
 .. doctest::
 
@@ -160,8 +160,6 @@ You can also add `keyword-only <https://docs.python.org/3/glossary.html#keyword-
     >>> A(a=1)
     A(a=1)
 
-``attrs`` supports ``kw_only`` attributes even on Python 2, though error messages are default python error messages and may be a bit confusing.
-
 ``kw_only`` may also be specified at via ``attr.s``, and will apply to all attributes:
 
 .. doctest::

From c228a64333def6168d6b5bf6a2e21101e7e6eb2a Mon Sep 17 00:00:00 2001
From: drinob <drinob@gmail.com>
Date: Thu, 15 Oct 2020 12:11:13 +0300
Subject: [PATCH 11/24] Moved functions back under if PY2 - seems codecov
 doesn't like them in module scope

---
 src/attr/_make.py | 51 ++++++++++++++++++++++++-----------------------
 1 file changed, 26 insertions(+), 25 deletions(-)

diff --git a/src/attr/_make.py b/src/attr/_make.py
index e3a636e40..86d14485c 100644
--- a/src/attr/_make.py
+++ b/src/attr/_make.py
@@ -223,7 +223,7 @@ def attrib(
     .. deprecated:: 19.2.0 *cmp* Removal on or after 2021-06-01.
     .. versionadded:: 19.2.0 *eq* and *order*
     .. versionadded:: 20.1.0 *on_setattr*
-    .. versionchanged:: 20.3.0 *kw_only* supported on python 2
+    .. versionchanged:: 20.3.0 *kw_only* backported to Python 2
     """
     eq, order = _determine_eq_order(cmp, eq, order, True)
 
@@ -1906,31 +1906,32 @@ def _assign_with_converter(attr_name, value_var, has_on_setattr):
     )
 
 
-def _unpack_kw_only_py2(attr_name, default=None):
-    """
-    Unpack *attr_name* from _kw_only dict.
-    """
-    if default is not None:
-        arg_default = ", %s" % default
-    else:
-        arg_default = ""
-    return "%s = _kw_only.pop('%s'%s)" % (
-        attr_name,
-        attr_name,
-        arg_default,
-    )
+if PY2:
+    def _unpack_kw_only_py2(attr_name, default=None):
+        """
+        Unpack *attr_name* from _kw_only dict.
+        """
+        if default is not None:
+            arg_default = ", %s" % default
+        else:
+            arg_default = ""
+        return "%s = _kw_only.pop('%s'%s)" % (
+            attr_name,
+            attr_name,
+            arg_default,
+        )
 
 
-def _unpack_kw_only_lines_py2(kw_only_args):
-    """
-    Unpack all *kw_only_args* from _kw_only dict and handle errors.
-    """
-    lines = ["try:"]
-    lines += [
-        "    " + _unpack_kw_only_py2(*arg.split("="))
-        for arg in kw_only_args
-    ]
-    lines += """\
+    def _unpack_kw_only_lines_py2(kw_only_args):
+        """
+        Unpack all *kw_only_args* from _kw_only dict and handle errors.
+        """
+        lines = ["try:"]
+        lines += [
+            "    " + _unpack_kw_only_py2(*arg.split("="))
+            for arg in kw_only_args
+        ]
+        lines += """\
 except KeyError as _key_error:
     _msg = '__init__() missing required keyword-only argument: %s'
     raise TypeError(_msg % _key_error)
@@ -1938,7 +1939,7 @@ def _unpack_kw_only_lines_py2(kw_only_args):
     _msg = '__init__() got an unexpected keyword argument %r'
     raise TypeError(_msg % next(iter(_kw_only)))
 """.split('\n')
-    return lines
+        return lines
 
 
 def _attrs_to_init_script(

From ca9600d12db6de99c1d9850b048aea8f9c66facb Mon Sep 17 00:00:00 2001
From: drinob <drinob@gmail.com>
Date: Thu, 15 Oct 2020 12:19:20 +0300
Subject: [PATCH 12/24] Blacked

---
 src/attr/_make.py | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/attr/_make.py b/src/attr/_make.py
index 86d14485c..cfbb302b1 100644
--- a/src/attr/_make.py
+++ b/src/attr/_make.py
@@ -1907,6 +1907,7 @@ def _assign_with_converter(attr_name, value_var, has_on_setattr):
 
 
 if PY2:
+
     def _unpack_kw_only_py2(attr_name, default=None):
         """
         Unpack *attr_name* from _kw_only dict.
@@ -1921,7 +1922,6 @@ def _unpack_kw_only_py2(attr_name, default=None):
             arg_default,
         )
 
-
     def _unpack_kw_only_lines_py2(kw_only_args):
         """
         Unpack all *kw_only_args* from _kw_only dict and handle errors.
@@ -1938,7 +1938,9 @@ def _unpack_kw_only_lines_py2(kw_only_args):
 if _kw_only:
     _msg = '__init__() got an unexpected keyword argument %r'
     raise TypeError(_msg % next(iter(_kw_only)))
-""".split('\n')
+""".split(
+            "\n"
+        )
         return lines
 
 

From 2dd691f776643373e11751c2c8b56c9600d2a11e Mon Sep 17 00:00:00 2001
From: drinob <drinob@gmail.com>
Date: Thu, 15 Oct 2020 12:58:19 +0300
Subject: [PATCH 13/24] Fixed changelog.d

---
 changelog.d/700.change.rst   | 1 +
 changelog.d/700.changing.rst | 1 -
 2 files changed, 1 insertion(+), 1 deletion(-)
 create mode 100644 changelog.d/700.change.rst
 delete mode 100644 changelog.d/700.changing.rst

diff --git a/changelog.d/700.change.rst b/changelog.d/700.change.rst
new file mode 100644
index 000000000..d4dc2dfd0
--- /dev/null
+++ b/changelog.d/700.change.rst
@@ -0,0 +1 @@
+``kw_only=True`` now works on Python 2.
diff --git a/changelog.d/700.changing.rst b/changelog.d/700.changing.rst
deleted file mode 100644
index 292a4d8d9..000000000
--- a/changelog.d/700.changing.rst
+++ /dev/null
@@ -1 +0,0 @@
-Added support for `kw_only=True` on Python 2.

From edd79f21aeb7bf71b6ea4af13af66992e04e42e2 Mon Sep 17 00:00:00 2001
From: drinob <drinob@gmail.com>
Date: Thu, 15 Oct 2020 13:08:03 +0300
Subject: [PATCH 14/24] Removed redundant brackets in test

---
 tests/test_make.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tests/test_make.py b/tests/test_make.py
index 534f5b8de..fad4ec7e2 100644
--- a/tests/test_make.py
+++ b/tests/test_make.py
@@ -789,7 +789,7 @@ class C(object):
         with pytest.raises(TypeError) as e:
             C(x=5, y=10)
 
-        assert ("got an unexpected keyword argument 'y'") in e.value.args[0]
+        assert "got an unexpected keyword argument 'y'" in e.value.args[0]
 
     def test_keyword_only_attributes_can_come_in_any_order(self):
         """

From b03f015f0a0cf37090035c2720b3b3b20d88e75e Mon Sep 17 00:00:00 2001
From: drinob <drinob@gmail.com>
Date: Thu, 15 Oct 2020 23:21:36 +0300
Subject: [PATCH 15/24] Added assertion to the _unpack_kw_only_lines_py2 - hope
 it will increase code coverage

---
 src/attr/_make.py | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/attr/_make.py b/src/attr/_make.py
index d269e3753..b4168a7f9 100644
--- a/src/attr/_make.py
+++ b/src/attr/_make.py
@@ -1945,6 +1945,7 @@ def _unpack_kw_only_lines_py2(kw_only_args):
         """
         Unpack all *kw_only_args* from _kw_only dict and handle errors.
         """
+        assert kw_only_args
         lines = ["try:"]
         lines += [
             "    " + _unpack_kw_only_py2(*arg.split("="))

From 6e15d380f0c1dc0afdd755c758fb56353c75b274 Mon Sep 17 00:00:00 2001
From: drinob <drinob@gmail.com>
Date: Thu, 15 Oct 2020 23:29:01 +0300
Subject: [PATCH 16/24] List comprehension -> for loop

---
 src/attr/_make.py | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/src/attr/_make.py b/src/attr/_make.py
index b4168a7f9..0c30448f3 100644
--- a/src/attr/_make.py
+++ b/src/attr/_make.py
@@ -1947,10 +1947,8 @@ def _unpack_kw_only_lines_py2(kw_only_args):
         """
         assert kw_only_args
         lines = ["try:"]
-        lines += [
-            "    " + _unpack_kw_only_py2(*arg.split("="))
-            for arg in kw_only_args
-        ]
+        for arg in kw_only_args:
+            lines.append("    " + _unpack_kw_only_py2(*arg.split("=")))
         lines += """\
 except KeyError as _key_error:
     _msg = '__init__() missing required keyword-only argument: %s'

From 42d5e427bbda57098473f7c7a3a370fbf0008592 Mon Sep 17 00:00:00 2001
From: drinob <drinob@gmail.com>
Date: Thu, 15 Oct 2020 23:42:31 +0300
Subject: [PATCH 17/24] lines.extend? I do not like for-loops

---
 src/attr/_make.py | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/attr/_make.py b/src/attr/_make.py
index 0c30448f3..b5794bb58 100644
--- a/src/attr/_make.py
+++ b/src/attr/_make.py
@@ -1947,8 +1947,10 @@ def _unpack_kw_only_lines_py2(kw_only_args):
         """
         assert kw_only_args
         lines = ["try:"]
-        for arg in kw_only_args:
+        lines.extend(
             lines.append("    " + _unpack_kw_only_py2(*arg.split("=")))
+            for arg in kw_only_args
+        )
         lines += """\
 except KeyError as _key_error:
     _msg = '__init__() missing required keyword-only argument: %s'

From 69c6de61b333d5a0369abac5bfd9577b2fb367a9 Mon Sep 17 00:00:00 2001
From: drinob <drinob@gmail.com>
Date: Thu, 15 Oct 2020 23:47:17 +0300
Subject: [PATCH 18/24] Fix code

---
 src/attr/_make.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/attr/_make.py b/src/attr/_make.py
index b5794bb58..c6f6cbb44 100644
--- a/src/attr/_make.py
+++ b/src/attr/_make.py
@@ -1948,7 +1948,7 @@ def _unpack_kw_only_lines_py2(kw_only_args):
         assert kw_only_args
         lines = ["try:"]
         lines.extend(
-            lines.append("    " + _unpack_kw_only_py2(*arg.split("=")))
+            "    " + _unpack_kw_only_py2(*arg.split("="))
             for arg in kw_only_args
         )
         lines += """\

From c0e0e06b5a77e7923aafd85916519b2013e35b41 Mon Sep 17 00:00:00 2001
From: drinob <drinob@gmail.com>
Date: Fri, 16 Oct 2020 11:22:26 +0300
Subject: [PATCH 19/24] Fixed style/added comment

---
 src/attr/_make.py | 18 +++++++++++++-----
 1 file changed, 13 insertions(+), 5 deletions(-)

diff --git a/src/attr/_make.py b/src/attr/_make.py
index c6f6cbb44..172ca83cd 100644
--- a/src/attr/_make.py
+++ b/src/attr/_make.py
@@ -1944,8 +1944,13 @@ def _unpack_kw_only_py2(attr_name, default=None):
     def _unpack_kw_only_lines_py2(kw_only_args):
         """
         Unpack all *kw_only_args* from _kw_only dict and handle errors.
+
+        Given a list of strings "{attr_name}" and "{attr_name}={attr_default}"
+        generate a list of lines "{attr_name} = _kw_only.pop('{attr_name}')"
+        and "{attr_name} = _kw_only.pop('{attr_name}', {attr_default}).
+        If required attr is missing in _kw_only dict or extra key is passed
+        - generated code raises TypeError with TypeError similar to builtins.
         """
-        assert kw_only_args
         lines = ["try:"]
         lines.extend(
             "    " + _unpack_kw_only_py2(*arg.split("="))
@@ -1953,11 +1958,14 @@ def _unpack_kw_only_lines_py2(kw_only_args):
         )
         lines += """\
 except KeyError as _key_error:
-    _msg = '__init__() missing required keyword-only argument: %s'
-    raise TypeError(_msg % _key_error)
+    raise TypeError(
+        '__init__() missing required keyword-only argument: %s' % _key_error
+    )
 if _kw_only:
-    _msg = '__init__() got an unexpected keyword argument %r'
-    raise TypeError(_msg % next(iter(_kw_only)))
+    raise TypeError(
+        '__init__() got an unexpected keyword argument %r' 
+        % next(iter(_kw_only))
+    )
 """.split(
             "\n"
         )

From f775c7af708def3cdffb3798f4caca2961bc500d Mon Sep 17 00:00:00 2001
From: drinob <drinob@gmail.com>
Date: Fri, 16 Oct 2020 11:22:40 +0300
Subject: [PATCH 20/24] Fixed docs (removed python2 mention)

---
 docs/examples.rst | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/examples.rst b/docs/examples.rst
index 8497734fc..0fac312a0 100644
--- a/docs/examples.rst
+++ b/docs/examples.rst
@@ -146,7 +146,7 @@ On Python 3 it overrides the implicit detection.
 Keyword-only Attributes
 ~~~~~~~~~~~~~~~~~~~~~~~
 
-You can also add `keyword-only <https://docs.python.org/3/glossary.html#keyword-only-parameter>`_ attributes (even on Python 2):
+You can also add `keyword-only <https://docs.python.org/3/glossary.html#keyword-only-parameter>`_ attributes:
 
 .. doctest::
 

From b5d04efab949291315506218b56608fa1383a33a Mon Sep 17 00:00:00 2001
From: drinob <drinob@gmail.com>
Date: Fri, 16 Oct 2020 11:26:19 +0300
Subject: [PATCH 21/24] Fix lint

---
 src/attr/_make.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/attr/_make.py b/src/attr/_make.py
index 172ca83cd..b2edfcae4 100644
--- a/src/attr/_make.py
+++ b/src/attr/_make.py
@@ -1963,7 +1963,7 @@ def _unpack_kw_only_lines_py2(kw_only_args):
     )
 if _kw_only:
     raise TypeError(
-        '__init__() got an unexpected keyword argument %r' 
+        '__init__() got an unexpected keyword argument %r'
         % next(iter(_kw_only))
     )
 """.split(

From 80cbb003437b06da6c871000745e7baaecaf5335 Mon Sep 17 00:00:00 2001
From: drinob <drinob@gmail.com>
Date: Fri, 16 Oct 2020 12:02:20 +0300
Subject: [PATCH 22/24] Better docstring

---
 src/attr/_make.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/attr/_make.py b/src/attr/_make.py
index b2edfcae4..6735e4678 100644
--- a/src/attr/_make.py
+++ b/src/attr/_make.py
@@ -1949,7 +1949,7 @@ def _unpack_kw_only_lines_py2(kw_only_args):
         generate a list of lines "{attr_name} = _kw_only.pop('{attr_name}')"
         and "{attr_name} = _kw_only.pop('{attr_name}', {attr_default}).
         If required attr is missing in _kw_only dict or extra key is passed
-        - generated code raises TypeError with TypeError similar to builtins.
+        - generated code raises TypeError similar to python builtin.
         """
         lines = ["try:"]
         lines.extend(

From e2ad8afb8a63e3fa10cc6c7da3d50e209ba6972a Mon Sep 17 00:00:00 2001
From: drinob <drinob@gmail.com>
Date: Fri, 16 Oct 2020 12:46:03 +0300
Subject: [PATCH 23/24] Rewritten docstring and added example code

---
 src/attr/_make.py | 20 +++++++++++++++-----
 1 file changed, 15 insertions(+), 5 deletions(-)

diff --git a/src/attr/_make.py b/src/attr/_make.py
index 6735e4678..68ad381a9 100644
--- a/src/attr/_make.py
+++ b/src/attr/_make.py
@@ -1945,11 +1945,21 @@ def _unpack_kw_only_lines_py2(kw_only_args):
         """
         Unpack all *kw_only_args* from _kw_only dict and handle errors.
 
-        Given a list of strings "{attr_name}" and "{attr_name}={attr_default}"
-        generate a list of lines "{attr_name} = _kw_only.pop('{attr_name}')"
-        and "{attr_name} = _kw_only.pop('{attr_name}', {attr_default}).
-        If required attr is missing in _kw_only dict or extra key is passed
-        - generated code raises TypeError similar to python builtin.
+        Given a list of strings {attr_name} and {attr_name}={default}
+        generates list of lines of code that pop attrs from _kw_only dict and
+        raise TypeError similar to builtin if required attr is missing or
+        extra key is passed.
+
+        >>> print("\n".join(_unpack_kw_only_lines_py2(["a", "b=42"])))
+        try:
+            a = _kw_only.pop('a')
+            b = _kw_only.pop('b', 42)
+        except KeyError as _key_error:
+            raise TypeError(
+                ...
+        if _kw_only:
+            raise TypeError(
+                ...
         """
         lines = ["try:"]
         lines.extend(

From 89cfd5fcaaaed74b286c32e9da69a5ee9ddb4932 Mon Sep 17 00:00:00 2001
From: drinob <drinob@gmail.com>
Date: Fri, 16 Oct 2020 12:52:42 +0300
Subject: [PATCH 24/24] Added quotes

---
 src/attr/_make.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/attr/_make.py b/src/attr/_make.py
index 68ad381a9..35d6e864d 100644
--- a/src/attr/_make.py
+++ b/src/attr/_make.py
@@ -1945,7 +1945,7 @@ def _unpack_kw_only_lines_py2(kw_only_args):
         """
         Unpack all *kw_only_args* from _kw_only dict and handle errors.
 
-        Given a list of strings {attr_name} and {attr_name}={default}
+        Given a list of strings "{attr_name}" and "{attr_name}={default}"
         generates list of lines of code that pop attrs from _kw_only dict and
         raise TypeError similar to builtin if required attr is missing or
         extra key is passed.