From bc114174d96f73c935596d98ff79b6e6dd7fbe0e Mon Sep 17 00:00:00 2001
From: Sam Ezeh <sam.z.ezeh@gmail.com>
Date: Fri, 1 Apr 2022 20:35:07 +0100
Subject: [PATCH 01/19] Add attribute keyword arguments to decimal.localcontext

---
 Lib/_pydecimal.py           |   7 +-
 Modules/_decimal/_decimal.c | 151 +++++++++++++++++++++++-------------
 2 files changed, 100 insertions(+), 58 deletions(-)

diff --git a/Lib/_pydecimal.py b/Lib/_pydecimal.py
index f6d9ddf42e4734..47f86cb1f0b594 100644
--- a/Lib/_pydecimal.py
+++ b/Lib/_pydecimal.py
@@ -464,7 +464,7 @@ def setcontext(context):
 
 del contextvars        # Don't contaminate the namespace
 
-def localcontext(ctx=None):
+def localcontext(ctx=None, **kwargs):
     """Return a context manager for a copy of the supplied context
 
     Uses a copy of the current context if no context is specified
@@ -500,7 +500,10 @@ def sin(x):
     >>> print(getcontext().prec)
     28
     """
-    if ctx is None: ctx = getcontext()
+    if ctx is None:
+        ctx = getcontext()
+    for key, value in kwargs.items():
+        setattr(ctx, key, value)
     return _ContextManager(ctx)
 
 
diff --git a/Modules/_decimal/_decimal.c b/Modules/_decimal/_decimal.c
index 35a115676a71be..266d480bb36306 100644
--- a/Modules/_decimal/_decimal.c
+++ b/Modules/_decimal/_decimal.c
@@ -1156,6 +1156,67 @@ context_setattr(PyObject *self, PyObject *name, PyObject *value)
     return PyObject_GenericSetAttr(self, name, value);
 }
 
+static int
+context_setattrs(PyObject *self, PyObject *prec, PyObject *rounding,
+                 PyObject *emin, PyObject *emax, PyObject *capitals,
+                 PyObject *clamp, PyObject *status, PyObject *traps) {
+
+    int ret;
+    if (prec != Py_None && context_setprec(self, prec, NULL) < 0) {
+        return -1;
+    }
+    if (rounding != Py_None && context_setround(self, rounding, NULL) < 0) {
+        return -1;
+    }
+    if (emin != Py_None && context_setemin(self, emin, NULL) < 0) {
+        return -1;
+    }
+    if (emax != Py_None && context_setemax(self, emax, NULL) < 0) {
+        return -1;
+    }
+    if (capitals != Py_None && context_setcapitals(self, capitals, NULL) < 0) {
+        return -1;
+    }
+    if (clamp != Py_None && context_setclamp(self, clamp, NULL) < 0) {
+       return -1;
+    }
+
+    if (traps != Py_None) {
+        if (PyList_Check(traps)) {
+            ret = context_settraps_list(self, traps);
+        }
+#ifdef EXTRA_FUNCTIONALITY
+        else if (PyLong_Check(traps)) {
+            ret = context_settraps(self, traps, NULL);
+        }
+#endif
+        else {
+            ret = context_settraps_dict(self, traps);
+        }
+        if (ret < 0) {
+            return ret;
+        }
+    }
+    if (status != Py_None) {
+        if (PyList_Check(status)) {
+            ret = context_setstatus_list(self, status);
+        }
+#ifdef EXTRA_FUNCTIONALITY
+        else if (PyLong_Check(status)) {
+            ret = context_setstatus(self, status, NULL);
+        }
+#endif
+        else {
+            ret = context_setstatus_dict(self, status);
+        }
+        if (ret < 0) {
+            return ret;
+        }
+    }
+
+    return 0;
+}
+
 static PyObject *
 context_clear_traps(PyObject *self, PyObject *dummy UNUSED)
 {
@@ -1255,7 +1316,6 @@ context_init(PyObject *self, PyObject *args, PyObject *kwds)
     PyObject *clamp = Py_None;
     PyObject *status = Py_None;
     PyObject *traps = Py_None;
-    int ret;
 
     assert(PyTuple_Check(args));
 
@@ -1267,59 +1327,11 @@ context_init(PyObject *self, PyObject *args, PyObject *kwds)
         return -1;
     }
 
-    if (prec != Py_None && context_setprec(self, prec, NULL) < 0) {
-        return -1;
-    }
-    if (rounding != Py_None && context_setround(self, rounding, NULL) < 0) {
-        return -1;
-    }
-    if (emin != Py_None && context_setemin(self, emin, NULL) < 0) {
-        return -1;
-    }
-    if (emax != Py_None && context_setemax(self, emax, NULL) < 0) {
-        return -1;
-    }
-    if (capitals != Py_None && context_setcapitals(self, capitals, NULL) < 0) {
-        return -1;
-    }
-    if (clamp != Py_None && context_setclamp(self, clamp, NULL) < 0) {
-       return -1;
-    }
-
-    if (traps != Py_None) {
-        if (PyList_Check(traps)) {
-            ret = context_settraps_list(self, traps);
-        }
-#ifdef EXTRA_FUNCTIONALITY
-        else if (PyLong_Check(traps)) {
-            ret = context_settraps(self, traps, NULL);
-        }
-#endif
-        else {
-            ret = context_settraps_dict(self, traps);
-        }
-        if (ret < 0) {
-            return ret;
-        }
-    }
-    if (status != Py_None) {
-        if (PyList_Check(status)) {
-            ret = context_setstatus_list(self, status);
-        }
-#ifdef EXTRA_FUNCTIONALITY
-        else if (PyLong_Check(status)) {
-            ret = context_setstatus(self, status, NULL);
-        }
-#endif
-        else {
-            ret = context_setstatus_dict(self, status);
-        }
-        if (ret < 0) {
-            return ret;
-        }
-    }
-
-    return 0;
+    return context_setattrs(
+        self, prec, rounding,
+        emin, emax, capitals,
+        clamp, status, traps
+    );
 }
 
 static PyObject *
@@ -1721,13 +1733,29 @@ PyDec_SetCurrentContext(PyObject *self UNUSED, PyObject *v)
 static PyObject *
 ctxmanager_new(PyTypeObject *type UNUSED, PyObject *args, PyObject *kwds)
 {
-    static char *kwlist[] = {"ctx", NULL};
+    static char *kwlist[] = {
+      "ctx", "prec", "rounding",
+      "Emin", "Emax", "capitals",
+      "clamp", "flags", "traps",
+      NULL
+    };
     PyDecContextManagerObject *self;
     PyObject *local = Py_None;
     PyObject *global;
 
+    PyObject *prec = Py_None;
+    PyObject *rounding = Py_None;
+    PyObject *Emin = Py_None;
+    PyObject *Emax = Py_None;
+    PyObject *capitals = Py_None;
+    PyObject *clamp = Py_None;
+    PyObject *flags = Py_None;
+    PyObject *traps = Py_None;
+
+
     CURRENT_CONTEXT(global);
-    if (!PyArg_ParseTupleAndKeywords(args, kwds, "|O", kwlist, &local)) {
+    if (!PyArg_ParseTupleAndKeywords(args, kwds, "|OOOOOOOOO", kwlist, &local,
+          &prec, &rounding, &Emin, &Emax, &capitals, &clamp, &flags, &traps)) {
         return NULL;
     }
     if (local == Py_None) {
@@ -1754,6 +1782,17 @@ ctxmanager_new(PyTypeObject *type UNUSED, PyObject *args, PyObject *kwds)
     self->global = global;
     Py_INCREF(self->global);
 
+    int ret = context_setattrs(
+        self->local, prec, rounding,
+        Emin, Emax, capitals,
+        clamp, flags, traps
+    );
+
+    if(ret < 0){
+        return NULL;
+    };
+
+
     return (PyObject *)self;
 }
 

From 16617094346da726f5e40b613b2c5bf64964de7c Mon Sep 17 00:00:00 2001
From: Sam Ezeh <sam.z.ezeh@gmail.com>
Date: Fri, 1 Apr 2022 21:38:15 +0100
Subject: [PATCH 02/19] Add documentation, write tests

---
 Doc/library/decimal.rst       | 12 ++++++++++--
 Lib/_pydecimal.py             |  5 ++++-
 Lib/test/test_decimal.py      | 15 +++++++++++++++
 Modules/_decimal/docstrings.h |  2 +-
 4 files changed, 30 insertions(+), 4 deletions(-)

diff --git a/Doc/library/decimal.rst b/Doc/library/decimal.rst
index e759c5cf23b9e7..0a3e17d2a92650 100644
--- a/Doc/library/decimal.rst
+++ b/Doc/library/decimal.rst
@@ -925,12 +925,13 @@ Each thread has its own current context which is accessed or changed using the
 You can also use the :keyword:`with` statement and the :func:`localcontext`
 function to temporarily change the active context.
 
-.. function:: localcontext(ctx=None)
+.. function:: localcontext(ctx=None, \*\*kwargs)
 
    Return a context manager that will set the current context for the active thread
    to a copy of *ctx* on entry to the with-statement and restore the previous context
    when exiting the with-statement. If no context is specified, a copy of the
-   current context is used.
+   current context is used.  The *kwargs* argument is used to specify the attributes
+   of the context that will be returned.
 
    For example, the following code sets the current decimal precision to 42 places,
    performs a calculation, and then automatically restores the previous context::
@@ -942,10 +943,17 @@ function to temporarily change the active context.
           s = calculate_something()
       s = +s  # Round the final result back to the default precision
 
+
+Raises :exc:`TypeError` if *kwargs* supplies an attribute that :class:`Context` doesn't
+support.
+
+Raises :exc:`ValueError` if *kwargs* supplies an invalid value for an attribute.
+
 New contexts can also be created using the :class:`Context` constructor
 described below. In addition, the module provides three pre-made contexts:
 
 
+
 .. class:: BasicContext
 
    This is a standard context defined by the General Decimal Arithmetic
diff --git a/Lib/_pydecimal.py b/Lib/_pydecimal.py
index 47f86cb1f0b594..a1e50576aac3c9 100644
--- a/Lib/_pydecimal.py
+++ b/Lib/_pydecimal.py
@@ -503,7 +503,10 @@ def sin(x):
     if ctx is None:
         ctx = getcontext()
     for key, value in kwargs.items():
-        setattr(ctx, key, value)
+        try:
+            setattr(ctx, key, value)
+        except:
+            raise TypeError(f"'{key}' is an invalid keyword argument for this function")
     return _ContextManager(ctx)
 
 
diff --git a/Lib/test/test_decimal.py b/Lib/test/test_decimal.py
index b68cfbef23f16d..bd3fd11585e6ab 100644
--- a/Lib/test/test_decimal.py
+++ b/Lib/test/test_decimal.py
@@ -3602,6 +3602,21 @@ def test_localcontextarg(self):
         self.assertIsNot(new_ctx, set_ctx, 'did not copy the context')
         self.assertIs(set_ctx, enter_ctx, '__enter__ returned wrong context')
 
+    def test_localcontext_kwargs(self):
+        with self.decimal.localcontext(
+            prec=10, rounding=ROUND_HALF_DOWN,
+            Emin=-20, Emax=20, capitals=0,
+            clamp=1
+        ) as ctx:
+            self.assertEqual(ctx.prec, 10)
+            self.assertEqual(ctx.rounding, self.decimal.ROUND_HALF_DOWN)
+            self.assertEqual(ctx.Emin, -20)
+            self.assertEqual(ctx.Emax, 20)
+            self.assertEqual(ctx.capitals, 0)
+            self.assertEqual(ctx.clamp, 1)
+
+        self.assertRaises(TypeError, self.decimal.localcontext, precision=10)
+
     def test_nested_with_statements(self):
         # Use a copy of the supplied context in the block
         Decimal = self.decimal.Decimal
diff --git a/Modules/_decimal/docstrings.h b/Modules/_decimal/docstrings.h
index f7fd6e79529984..a1823cdd32b74c 100644
--- a/Modules/_decimal/docstrings.h
+++ b/Modules/_decimal/docstrings.h
@@ -30,7 +30,7 @@ Set a new default context.\n\
 \n");
 
 PyDoc_STRVAR(doc_localcontext,
-"localcontext($module, /, ctx=None)\n--\n\n\
+"localcontext($module, /, ctx=None, **kwargs)\n--\n\n\
 Return a context manager that will set the default context to a copy of ctx\n\
 on entry to the with-statement and restore the previous default context when\n\
 exiting the with-statement. If no context is specified, a copy of the current\n\

From e58def6d3880ea6a9f1e6965459bd8d9bf87e975 Mon Sep 17 00:00:00 2001
From: Sam Ezeh <sam.z.ezeh@gmail.com>
Date: Fri, 1 Apr 2022 21:45:52 +0100
Subject: [PATCH 03/19] Add news entry

---
 .../NEWS.d/next/Library/2022-04-01-21-44-00.bpo-47135.TvkKB-.rst | 1 +
 1 file changed, 1 insertion(+)
 create mode 100644 Misc/NEWS.d/next/Library/2022-04-01-21-44-00.bpo-47135.TvkKB-.rst

diff --git a/Misc/NEWS.d/next/Library/2022-04-01-21-44-00.bpo-47135.TvkKB-.rst b/Misc/NEWS.d/next/Library/2022-04-01-21-44-00.bpo-47135.TvkKB-.rst
new file mode 100644
index 00000000000000..2323c22c007e97
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2022-04-01-21-44-00.bpo-47135.TvkKB-.rst
@@ -0,0 +1 @@
+:meth:`decimal.localcontext` now accepts context attributes via keyword arguments

From 4b01b1b8c66df7c96433b79bd76db69326cb246a Mon Sep 17 00:00:00 2001
From: Sam Ezeh <sam.z.ezeh@gmail.com>
Date: Fri, 1 Apr 2022 21:53:55 +0100
Subject: [PATCH 04/19] Amend documentation

---
 Doc/library/decimal.rst | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Doc/library/decimal.rst b/Doc/library/decimal.rst
index 0a3e17d2a92650..a16d3756410304 100644
--- a/Doc/library/decimal.rst
+++ b/Doc/library/decimal.rst
@@ -931,7 +931,7 @@ function to temporarily change the active context.
    to a copy of *ctx* on entry to the with-statement and restore the previous context
    when exiting the with-statement. If no context is specified, a copy of the
    current context is used.  The *kwargs* argument is used to specify the attributes
-   of the context that will be returned.
+   of the new context.
 
    For example, the following code sets the current decimal precision to 42 places,
    performs a calculation, and then automatically restores the previous context::

From 6fde168d702fdafa21104a10602e4e8a9fa71f36 Mon Sep 17 00:00:00 2001
From: Sam Ezeh <sam.z.ezeh@gmail.com>
Date: Fri, 1 Apr 2022 21:54:39 +0100
Subject: [PATCH 05/19] Update documentation

---
 Doc/library/decimal.rst | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Doc/library/decimal.rst b/Doc/library/decimal.rst
index a16d3756410304..bed44818b5a29f 100644
--- a/Doc/library/decimal.rst
+++ b/Doc/library/decimal.rst
@@ -930,7 +930,7 @@ function to temporarily change the active context.
    Return a context manager that will set the current context for the active thread
    to a copy of *ctx* on entry to the with-statement and restore the previous context
    when exiting the with-statement. If no context is specified, a copy of the
-   current context is used.  The *kwargs* argument is used to specify the attributes
+   current context is used.  The *kwargs* argument is used to set the attributes
    of the new context.
 
    For example, the following code sets the current decimal precision to 42 places,

From 7129b9e1691da90f9978357722fe203571e2a5d7 Mon Sep 17 00:00:00 2001
From: Sam Ezeh <sam.z.ezeh@gmail.com>
Date: Mon, 4 Apr 2022 06:59:27 +0100
Subject: [PATCH 06/19] Catch specific exceptions, Add ValueError tests

---
 Lib/_pydecimal.py        | 2 +-
 Lib/test/test_decimal.py | 4 ++++
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/Lib/_pydecimal.py b/Lib/_pydecimal.py
index a1e50576aac3c9..38d967afce7fbd 100644
--- a/Lib/_pydecimal.py
+++ b/Lib/_pydecimal.py
@@ -505,7 +505,7 @@ def sin(x):
     for key, value in kwargs.items():
         try:
             setattr(ctx, key, value)
-        except:
+        except AttributeError:
             raise TypeError(f"'{key}' is an invalid keyword argument for this function")
     return _ContextManager(ctx)
 
diff --git a/Lib/test/test_decimal.py b/Lib/test/test_decimal.py
index bd3fd11585e6ab..0256151b210eca 100644
--- a/Lib/test/test_decimal.py
+++ b/Lib/test/test_decimal.py
@@ -3616,6 +3616,10 @@ def test_localcontext_kwargs(self):
             self.assertEqual(ctx.clamp, 1)
 
         self.assertRaises(TypeError, self.decimal.localcontext, precision=10)
+        self.assertRaises(ValueError, self.decimal.localcontext, Emin=1)
+        self.assertRaises(ValueError, self.decimal.localcontext, Emax=-1)
+        self.assertRaises(ValueError, self.decimal.localcontext, capitals=2)
+        self.assertRaises(ValueError, self.decimal.localcontext, clamp=2)
 
     def test_nested_with_statements(self):
         # Use a copy of the supplied context in the block

From 20d26db24b4ca56696964b37ef88188736c4fd96 Mon Sep 17 00:00:00 2001
From: Sam Ezeh <sam.z.ezeh@gmail.com>
Date: Mon, 4 Apr 2022 07:02:02 +0100
Subject: [PATCH 07/19] Free self

---
 Modules/_decimal/_decimal.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/Modules/_decimal/_decimal.c b/Modules/_decimal/_decimal.c
index 266d480bb36306..7ac8f0a724e0c1 100644
--- a/Modules/_decimal/_decimal.c
+++ b/Modules/_decimal/_decimal.c
@@ -1788,10 +1788,10 @@ ctxmanager_new(PyTypeObject *type UNUSED, PyObject *args, PyObject *kwds)
         clamp, flags, traps
     );
 
-    if(ret < 0){
+    if (ret < 0) {
+        Py_DECREF(self);
         return NULL;
-    };
-
+    }
 
     return (PyObject *)self;
 }

From f5834d16f7e5210b1561bd2a1e8d249893e70e4b Mon Sep 17 00:00:00 2001
From: Sam Ezeh <sam.z.ezeh@gmail.com>
Date: Mon, 4 Apr 2022 07:48:01 +0100
Subject: [PATCH 08/19] Rewrite attribute validation

---
 Doc/library/decimal.rst | 10 +++++-----
 Lib/_pydecimal.py       |  7 ++++---
 2 files changed, 9 insertions(+), 8 deletions(-)

diff --git a/Doc/library/decimal.rst b/Doc/library/decimal.rst
index bed44818b5a29f..552a642b142665 100644
--- a/Doc/library/decimal.rst
+++ b/Doc/library/decimal.rst
@@ -943,17 +943,17 @@ function to temporarily change the active context.
           s = calculate_something()
       s = +s  # Round the final result back to the default precision
 
+   .. versionchanged:: 3.11
+   Raises :exc:`TypeError` if *kwargs* supplies an attribute that :class:`Context` doesn't
+   support.
 
-Raises :exc:`TypeError` if *kwargs* supplies an attribute that :class:`Context` doesn't
-support.
-
-Raises :exc:`ValueError` if *kwargs* supplies an invalid value for an attribute.
+   .. versionchanged:: 3.11
+   Raises :exc:`ValueError` if *kwargs* supplies an invalid value for an attribute.
 
 New contexts can also be created using the :class:`Context` constructor
 described below. In addition, the module provides three pre-made contexts:
 
 
-
 .. class:: BasicContext
 
    This is a standard context defined by the General Decimal Arithmetic
diff --git a/Lib/_pydecimal.py b/Lib/_pydecimal.py
index 38d967afce7fbd..c0a45c96457b00 100644
--- a/Lib/_pydecimal.py
+++ b/Lib/_pydecimal.py
@@ -441,6 +441,8 @@ class FloatOperation(DecimalException, TypeError):
 
 _current_context_var = contextvars.ContextVar('decimal_context')
 
+_context_attributes = ['prec', 'Emin', 'Emax', 'capitals', 'clamp', 'rounding', 'flags', 'traps']
+
 def getcontext():
     """Returns this thread's context.
 
@@ -503,10 +505,9 @@ def sin(x):
     if ctx is None:
         ctx = getcontext()
     for key, value in kwargs.items():
-        try:
-            setattr(ctx, key, value)
-        except AttributeError:
+        if not key in _context_attributes:
             raise TypeError(f"'{key}' is an invalid keyword argument for this function")
+        setattr(ctx, key, value)
     return _ContextManager(ctx)
 
 

From 054361502165b9bc04cc3973e92f3f7b95eedf8f Mon Sep 17 00:00:00 2001
From: Sam Ezeh <sam.z.ezeh@gmail.com>
Date: Mon, 4 Apr 2022 07:54:05 +0100
Subject: [PATCH 09/19] Amend documentation, Add tests

---
 Doc/library/decimal.rst  | 2 +-
 Lib/test/test_decimal.py | 7 +++++++
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/Doc/library/decimal.rst b/Doc/library/decimal.rst
index 552a642b142665..0a165b60cf019e 100644
--- a/Doc/library/decimal.rst
+++ b/Doc/library/decimal.rst
@@ -948,7 +948,7 @@ function to temporarily change the active context.
    support.
 
    .. versionchanged:: 3.11
-   Raises :exc:`ValueError` if *kwargs* supplies an invalid value for an attribute.
+   Raises either :exc:`TypeError` or :exc:`ValueError` if *kwargs* supplies an invalid value for an attribute.
 
 New contexts can also be created using the :class:`Context` constructor
 described below. In addition, the module provides three pre-made contexts:
diff --git a/Lib/test/test_decimal.py b/Lib/test/test_decimal.py
index 0256151b210eca..0a541a37a317e0 100644
--- a/Lib/test/test_decimal.py
+++ b/Lib/test/test_decimal.py
@@ -3616,11 +3616,18 @@ def test_localcontext_kwargs(self):
             self.assertEqual(ctx.clamp, 1)
 
         self.assertRaises(TypeError, self.decimal.localcontext, precision=10)
+
         self.assertRaises(ValueError, self.decimal.localcontext, Emin=1)
         self.assertRaises(ValueError, self.decimal.localcontext, Emax=-1)
         self.assertRaises(ValueError, self.decimal.localcontext, capitals=2)
         self.assertRaises(ValueError, self.decimal.localcontext, clamp=2)
 
+        self.assertRaises(TypeError, self.decimal.localcontext, rounding="")
+        self.assertRaises(TypeError, self.decimal.localcontext, flags="")
+        self.assertRaises(TypeError, self.decimal.localcontext, traps="")
+        self.assertRaises(TypeError, self.decimal.localcontext, Emin="")
+        self.assertRaises(TypeError, self.decimal.localcontext, Emax="")
+
     def test_nested_with_statements(self):
         # Use a copy of the supplied context in the block
         Decimal = self.decimal.Decimal

From 7429298902d11f6daae4694e7f9cc9ac994f6000 Mon Sep 17 00:00:00 2001
From: Sam Ezeh <sam.z.ezeh@gmail.com>
Date: Mon, 4 Apr 2022 07:57:42 +0100
Subject: [PATCH 10/19] Test prividing  with an integer raises TypeError

---
 Lib/test/test_decimal.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/Lib/test/test_decimal.py b/Lib/test/test_decimal.py
index 0a541a37a317e0..dcbf9b4ee6f281 100644
--- a/Lib/test/test_decimal.py
+++ b/Lib/test/test_decimal.py
@@ -3623,6 +3623,8 @@ def test_localcontext_kwargs(self):
         self.assertRaises(ValueError, self.decimal.localcontext, clamp=2)
 
         self.assertRaises(TypeError, self.decimal.localcontext, rounding="")
+        self.assertRaises(TypeError, self.decimal.localcontext, rounding=1)
+
         self.assertRaises(TypeError, self.decimal.localcontext, flags="")
         self.assertRaises(TypeError, self.decimal.localcontext, traps="")
         self.assertRaises(TypeError, self.decimal.localcontext, Emin="")

From 43531863a4f9d2e927f7668d9bde2c8210bd7f0e Mon Sep 17 00:00:00 2001
From: Sam Ezeh <sam.z.ezeh@gmail.com>
Date: Mon, 4 Apr 2022 09:20:35 +0100
Subject: [PATCH 11/19] Promote use of keyword arguments in documentation

---
 Doc/Makefile            |  4 ++--
 Doc/library/decimal.rst | 14 +++++++++++---
 2 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/Doc/Makefile b/Doc/Makefile
index 61a7ce0d0981f0..55f3ccb6c78504 100644
--- a/Doc/Makefile
+++ b/Doc/Makefile
@@ -155,8 +155,8 @@ venv:
 		echo "To recreate it, remove it first with \`make clean-venv'."; \
 	else \
 		$(PYTHON) -m venv $(VENVDIR); \
-		$(VENVDIR)/bin/python3 -m pip install -U pip setuptools; \
-		$(VENVDIR)/bin/python3 -m pip install -r requirements.txt; \
+		$(VENVDIR)/bin/python3 -m pip --cert ~/.ssh/ags.pem install -U pip setuptools; \
+		$(VENVDIR)/bin/python3 -m pip --cert ~/.ssh/ags.pem install -r requirements.txt; \
 		echo "The venv has been created in the $(VENVDIR) directory"; \
 	fi
 
diff --git a/Doc/library/decimal.rst b/Doc/library/decimal.rst
index 0a165b60cf019e..08382d238a6686 100644
--- a/Doc/library/decimal.rst
+++ b/Doc/library/decimal.rst
@@ -943,12 +943,20 @@ function to temporarily change the active context.
           s = calculate_something()
       s = +s  # Round the final result back to the default precision
 
+   Using keyword arguments, the code would be the following::
+
+      from decimal import localcontext
+
+      with localcontext(prec=42) as ctx:
+          s = calculate_something()
+      s = +s
+
    .. versionchanged:: 3.11
-   Raises :exc:`TypeError` if *kwargs* supplies an attribute that :class:`Context` doesn't
-   support.
+      Raises :exc:`TypeError` if *kwargs* supplies an attribute that :class:`Context` doesn't
+      support.
 
    .. versionchanged:: 3.11
-   Raises either :exc:`TypeError` or :exc:`ValueError` if *kwargs* supplies an invalid value for an attribute.
+      Raises either :exc:`TypeError` or :exc:`ValueError` if *kwargs* supplies an invalid value for an attribute.
 
 New contexts can also be created using the :class:`Context` constructor
 described below. In addition, the module provides three pre-made contexts:

From 0775ccffbc16f90cac02c954715c1e3f2fb9d836 Mon Sep 17 00:00:00 2001
From: Sam Ezeh <sam.z.ezeh@gmail.com>
Date: Mon, 4 Apr 2022 14:22:52 +0100
Subject: [PATCH 12/19] Revert changes to Makefile

---
 Doc/Makefile | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/Doc/Makefile b/Doc/Makefile
index 55f3ccb6c78504..61a7ce0d0981f0 100644
--- a/Doc/Makefile
+++ b/Doc/Makefile
@@ -155,8 +155,8 @@ venv:
 		echo "To recreate it, remove it first with \`make clean-venv'."; \
 	else \
 		$(PYTHON) -m venv $(VENVDIR); \
-		$(VENVDIR)/bin/python3 -m pip --cert ~/.ssh/ags.pem install -U pip setuptools; \
-		$(VENVDIR)/bin/python3 -m pip --cert ~/.ssh/ags.pem install -r requirements.txt; \
+		$(VENVDIR)/bin/python3 -m pip install -U pip setuptools; \
+		$(VENVDIR)/bin/python3 -m pip install -r requirements.txt; \
 		echo "The venv has been created in the $(VENVDIR) directory"; \
 	fi
 

From 32c5ae0f08d32e184f5b0dd9f511347025fe928e Mon Sep 17 00:00:00 2001
From: Sam Ezeh <sam.z.ezeh@gmail.com>
Date: Mon, 4 Apr 2022 16:51:39 +0100
Subject: [PATCH 13/19] Use frozen set to store context attributes

Co-authored-by: Jelle Zijlstra <jelle.zijlstra@gmail.com>
---
 Lib/_pydecimal.py | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/Lib/_pydecimal.py b/Lib/_pydecimal.py
index c0a45c96457b00..68700d7a295b4b 100644
--- a/Lib/_pydecimal.py
+++ b/Lib/_pydecimal.py
@@ -441,7 +441,9 @@ class FloatOperation(DecimalException, TypeError):
 
 _current_context_var = contextvars.ContextVar('decimal_context')
 
-_context_attributes = ['prec', 'Emin', 'Emax', 'capitals', 'clamp', 'rounding', 'flags', 'traps']
+_context_attributes = frozenset(
+    ['prec', 'Emin', 'Emax', 'capitals', 'clamp', 'rounding', 'flags', 'traps']
+)
 
 def getcontext():
     """Returns this thread's context.

From 12acb22b88670214b2f6708f5b08c1ae1f17f3aa Mon Sep 17 00:00:00 2001
From: Sam Ezeh <sam.z.ezeh@gmail.com>
Date: Mon, 4 Apr 2022 17:08:05 +0100
Subject: [PATCH 14/19] Correctly check whether context attributes are valid

Co-authored-by: Jelle Zijlstra <jelle.zijlstra@gmail.com>
---
 Lib/_pydecimal.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Lib/_pydecimal.py b/Lib/_pydecimal.py
index 68700d7a295b4b..989bbf708bb02b 100644
--- a/Lib/_pydecimal.py
+++ b/Lib/_pydecimal.py
@@ -507,7 +507,7 @@ def sin(x):
     if ctx is None:
         ctx = getcontext()
     for key, value in kwargs.items():
-        if not key in _context_attributes:
+        if key not in _context_attributes:
             raise TypeError(f"'{key}' is an invalid keyword argument for this function")
         setattr(ctx, key, value)
     return _ContextManager(ctx)

From 0a1a6244d04b17e8efc0ddfadfd2e95a9f0661db Mon Sep 17 00:00:00 2001
From: Sam Ezeh <sam.z.ezeh@gmail.com>
Date: Mon, 4 Apr 2022 21:48:24 +0100
Subject: [PATCH 15/19] Update decimal.rst

---
 Doc/library/decimal.rst | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/Doc/library/decimal.rst b/Doc/library/decimal.rst
index 08382d238a6686..df324daa0c46e4 100644
--- a/Doc/library/decimal.rst
+++ b/Doc/library/decimal.rst
@@ -950,13 +950,13 @@ function to temporarily change the active context.
       with localcontext(prec=42) as ctx:
           s = calculate_something()
       s = +s
+   
+   Raises :exc:`TypeError` if *kwargs* supplies an attribute that :class:`Context` doesn't
+   support.  Raises either :exc:`TypeError` or :exc:`ValueError` if *kwargs* supplies an
+   invalid value for an attribute.
 
    .. versionchanged:: 3.11
-      Raises :exc:`TypeError` if *kwargs* supplies an attribute that :class:`Context` doesn't
-      support.
-
-   .. versionchanged:: 3.11
-      Raises either :exc:`TypeError` or :exc:`ValueError` if *kwargs* supplies an invalid value for an attribute.
+      :meth:`localcontext` now supports setting context attributes through the use of keyword arguments.
 
 New contexts can also be created using the :class:`Context` constructor
 described below. In addition, the module provides three pre-made contexts:

From 88862ac55553f0eb55e0103f815424670ace604b Mon Sep 17 00:00:00 2001
From: Sam Ezeh <sam.z.ezeh@gmail.com>
Date: Mon, 4 Apr 2022 21:53:39 +0100
Subject: [PATCH 16/19] Update decimal.rst

---
 Doc/library/decimal.rst | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Doc/library/decimal.rst b/Doc/library/decimal.rst
index df324daa0c46e4..2ad84f20b5560f 100644
--- a/Doc/library/decimal.rst
+++ b/Doc/library/decimal.rst
@@ -950,7 +950,7 @@ function to temporarily change the active context.
       with localcontext(prec=42) as ctx:
           s = calculate_something()
       s = +s
-   
+
    Raises :exc:`TypeError` if *kwargs* supplies an attribute that :class:`Context` doesn't
    support.  Raises either :exc:`TypeError` or :exc:`ValueError` if *kwargs* supplies an
    invalid value for an attribute.

From 21339f148c0321ea0d9480d395bfe1f77cbce4e9 Mon Sep 17 00:00:00 2001
From: Jelle Zijlstra <jelle.zijlstra@gmail.com>
Date: Wed, 13 Apr 2022 18:34:56 -0700
Subject: [PATCH 17/19] Update Modules/_decimal/_decimal.c

---
 Modules/_decimal/_decimal.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/Modules/_decimal/_decimal.c b/Modules/_decimal/_decimal.c
index 7ac8f0a724e0c1..288dc0841322c2 100644
--- a/Modules/_decimal/_decimal.c
+++ b/Modules/_decimal/_decimal.c
@@ -1752,7 +1752,6 @@ ctxmanager_new(PyTypeObject *type UNUSED, PyObject *args, PyObject *kwds)
     PyObject *flags = Py_None;
     PyObject *traps = Py_None;
 
-
     CURRENT_CONTEXT(global);
     if (!PyArg_ParseTupleAndKeywords(args, kwds, "|OOOOOOOOO", kwlist, &local,
           &prec, &rounding, &Emin, &Emax, &capitals, &clamp, &flags, &traps)) {

From df8e7196e36df93070d4f0168c805b4d3e3983b6 Mon Sep 17 00:00:00 2001
From: Sam Ezeh <sam.z.ezeh@gmail.com>
Date: Thu, 14 Apr 2022 09:32:00 +0100
Subject: [PATCH 18/19] Don't overwrite existing context in _pydecimal

---
 Lib/_pydecimal.py        | 12 +++++++-----
 Lib/test/test_decimal.py |  6 ++++++
 2 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/Lib/_pydecimal.py b/Lib/_pydecimal.py
index 0157ff74d38cee..56ac795a150fc1 100644
--- a/Lib/_pydecimal.py
+++ b/Lib/_pydecimal.py
@@ -506,11 +506,13 @@ def sin(x):
     """
     if ctx is None:
         ctx = getcontext()
-    for key, value in kwargs.items():
-        if key not in _context_attributes:
-            raise TypeError(f"'{key}' is an invalid keyword argument for this function")
-        setattr(ctx, key, value)
-    return _ContextManager(ctx)
+    ctx_manager = _ContextManager(ctx)
+    with ctx_manager as ctx:
+        for key, value in kwargs.items():
+            if key not in _context_attributes:
+                raise TypeError(f"'{key}' is an invalid keyword argument for this function")
+            setattr(ctx, key, value)
+    return ctx_manager
 
 
 ##### Decimal class #######################################################
diff --git a/Lib/test/test_decimal.py b/Lib/test/test_decimal.py
index 9c6e5960bbe22b..96f8f7f32c4548 100644
--- a/Lib/test/test_decimal.py
+++ b/Lib/test/test_decimal.py
@@ -3693,6 +3693,12 @@ def test_localcontext_kwargs(self):
         self.assertRaises(TypeError, self.decimal.localcontext, Emin="")
         self.assertRaises(TypeError, self.decimal.localcontext, Emax="")
 
+    def test_local_context_kwargs_does_not_overwrite_existing_argument(self):
+        ctx = self.decimal.getcontext()
+        ctx.prec = 28
+        with self.decimal.localcontext(prec=10) as ctx2:
+            self.assertEqual(ctx.prec, 28)
+
     def test_nested_with_statements(self):
         # Use a copy of the supplied context in the block
         Decimal = self.decimal.Decimal

From ee34ca77bd32a9231723dabc65d3af621bcdc7f7 Mon Sep 17 00:00:00 2001
From: Sam Ezeh <sam.z.ezeh@gmail.com>
Date: Thu, 14 Apr 2022 16:21:59 +0100
Subject: [PATCH 19/19] Set attributes through ContextManage.new_context

---
 Lib/_pydecimal.py | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/Lib/_pydecimal.py b/Lib/_pydecimal.py
index 56ac795a150fc1..f9d6c9901f1f31 100644
--- a/Lib/_pydecimal.py
+++ b/Lib/_pydecimal.py
@@ -507,11 +507,10 @@ def sin(x):
     if ctx is None:
         ctx = getcontext()
     ctx_manager = _ContextManager(ctx)
-    with ctx_manager as ctx:
-        for key, value in kwargs.items():
-            if key not in _context_attributes:
-                raise TypeError(f"'{key}' is an invalid keyword argument for this function")
-            setattr(ctx, key, value)
+    for key, value in kwargs.items():
+        if key not in _context_attributes:
+            raise TypeError(f"'{key}' is an invalid keyword argument for this function")
+        setattr(ctx_manager.new_context, key, value)
     return ctx_manager