Add detail to docs on constraints changes with new resolver
Related to
@@ -1449,22 +1449,27 @@ install x y`` in a single command. We would like your thoughts on what
pip's behavior should be; please answer `our survey on upgrades that
create conflicts`_.
-We are also changing our support for :ref:`Constraints Files` and
-related functionality. We did a fairly comprehensive overhaul and
-stripped constraints files down to being purely a way to specify
-global (version) limits for packages. Specifically:
+We are also changing our support for :ref:`Constraints Files`,
+editable installs, and related functionality. We did a fairly
+comprehensive overhaul and stripped constraints files down to being
+purely a way to specify global (version) limits for packages, and so
+some combinations that used to be allowed will now cause
+errors. Specifically:
* Constraints don't override the existing requirements; they simply
constrain what versions are visible as input to the resolver (see
:issue:`9020`)
-
* Providing an editable requirement (``-e .``) does not cause pip to
- ignore version specifiers or constraints (see :issue:`8076`)
-
+ ignore version specifiers or constraints (see :issue:`8076`), and if
+ you have a conflict between a pinned requirement and a local
+ directory then pip will indicate that it cannot find a version
+ satisfying both (see :issue:`8307`)
* Hash-checking mode requires that all requirements are specified as a
- `==` match on a version and may not work well in combination with
+ ``==`` match on a version and may not work well in combination with
constraints (see :issue:`9020` and :issue:`8792`)
-
+* If necessary to satisfy constraints, pip will happily reinstall
+ packages, upgrading or downgrading, without needing any additional
+ command-line options (see :issue:`8115` and :doc:`development/architecture/upgrade-options`)
* Unnamed requirements are not allowed as constraints (see :issue:`6628` and :issue:`8210`)
* Links are not allowed as constraints (see :issue:`8253`)
* Constraints cannot have extras (see :issue:`6628`)
