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We are happy to announce the third alpha release of opam 2.2.0. It contains
some fixes and a new feature for Windows. You can view the full list in the
release note.
This version is an alpha, we invite users to test it to spot previously
unnoticed bugs as we head towards the stable release.
Major change: Environment variables handling on Windows
opam files now support a new x-env-path-rewrite field which
specifies rewriting rules for the environment variable updates defined in
the setenv and build-env fields. This field allows greater control over the
separator character used for PATH-like fields (i.e. ; vs :), conversion of
slashes to backslashes, and even conversion from Windows native path format
(C:\cygwin64\home\dra\.opam) to Cygwin format (/home/dra/.opam).
The rewriting rules allow opam directory-like variables (e.g. the %{lib}% directory
of a switch) to be used in setenv and build-env fields in a portable way.
For example, given:
setenv: [
[PKG_CONFIG_PATH += "%{lib}%/pkgconfig"]
[PATH += "%{share}%/bin"]
]
x-env-path-rewrite: [
[ PKG_CONFIG_PATH ":" "host" ]
[ PATH (":" {os != "win32"} | ";" {os = "win32"}) ("target" {os != "win32"} | "target-quoted" {os = "win32"}) ]
]
the environment variable changes given by opam env on Windows would be:
PKG_CONFIG_PATH='/cygdrive/c/Users/DRA/AppData/Local/opam/default/lib/pkgconfig[:<rest-of-PKG_CONFIG_PATH, if given>]'
PATH='C:\Users\DRA\AppData\Local\opam\default\share\bin;C:\Users\DRA\AppData\Local\opam\default\bin;<rest-of-PATH>'
with the following interesting parts for Windows users:
PKG_CONFIG_PATH, which is consumed by a Cygwin-tool, has the directory given in Unix-like syntax, and opam's share variable was automatically converted- The correct separator is used for each (
: for PKG_CONFIG_PATH, ; for PATH is used when adding entries)
- In the
PATH update, /bin was converted to \bin
Note that the specification for PATH is opam's default behaviour, so it's not actually necessary to have this formula for PATH in the x-env-path-rewrite field.
The full syntax is described in full in the manual.
Opam files carrying this new field are still compatible with the opam 2.0 syntax as it is an extension field, however its effect is only available with opam 2.2.0~alpha3 and above.
If you want to make sure users of the package containing it have a compatible opam, you can use the available field to that end:
available: opam-version >= "2.2.0~alpha3"
or, if the change is Windows-specific:
available: opam-version >= "2.2.0~alpha3" | os != "win32"
Other noteworthy changes
- Sandbox:
/tmp is now writable again, restoring POSIX compliance
- opam tree:
opam tree package.version is now supported, displaying the dependency tree of a specific version of a package
- opam tree:
--recurse and --subpath are supported for directory arguments
- opam admin: new
add-extrafiles command to add/check/update the extra-files: field according to the files present in the files/ directory
- opam lint: new syntax allow marking a set of warnings as errors e.g.
-W @1..9
- Releases: Pre-built binaries now include ppc64le and s390x
Miscellaneous changes
- A handful of issues related to the compilation of opam on Windows were fixed
- Bugs in the handling of the
OPAMCURL, OPAMFETCH and OPAMVERBOSE environment variables were fixed
- Bugs in the handling of the
--assume-built argument were fixed
- Sporadic crashes and segfaults during shell detection on Windows were fixed
Various other improvements were made and bugs were fixed.
API changes are denoted in the release note linked above.
This release also includes a handful of PRs improving the documentation and more than a dozen PRs improving and extending the tests.
Windows Support
The main opam-repository Windows compliance is still a work in progress, we
recommend to use existing compatible
repository (originally
from @fdopen) and 32/64 bit mingw-w64
packages (by
@dra27).
How to Test opam on Windows
If you're feeling adventurous, you can use the experimental pre-built binary for Windows available here. It should work but since it's our first public pre-built binary for Windows please use at your own risk.
Otherwise you can compile opam yourself using the following steps:
This alpha requires a preexisting Cygwin installation for compiling opam.
- Check that you have all dependencies installed:
autoconf, make, patch, curl- MinGW compilers:
mingw64-x86_64-gcc-g++, mingw64-i686-gcc-g++
- Or if you want to use the MSVC port of OCaml, you'll need to install Visual Studio or Visual Studio Build Tools
- Download & extract the opam archive
- In the directory:
- if you are using MSVC: launch
make cold
- if you are using MinGW: make sure the path to the
libc dlls are in your PATH and launch make cold. For instance: export PATH='C:\cygwin64\usr\x86_64-w64-mingw32\sys-root\mingw\bin':$PATH && make cold. Don’t forget to update PATH accordingly or place the opam binary in the same directory as the libc dlls if you want to move the resulting opam binary.
- alternatively, if you're using MinGW:
make cold CONFIGURE_ARGS=--with-private-runtime. If you change the location of the resulting opam binary, don't forget to copy Opam.Runtime.amd64 directory (or Opam.Runtime.i386) in the same directory.
- A coffee later, you now have an opam executable!
- Start your preferred Windows terminal (
cmd or PowerShell), and initialise opam with the Windows sunset repository:
opam init git+https://github.com/ocaml-opam/opam-repository-mingw
From here, you can try to install the sunset
repository
packages. If you find any bugs, please submit an
issue.
It will help opam-repository maintainers to add Windows repository packages
into the main repository.
Try it!
In case you plan a possible rollback, you may want to first backup your
~/.opam directory.
The upgrade instructions are unchanged:
-
Either from binaries: run
bash -c "sh <(curl -fsSL https://raw.githubusercontent.com/ocaml/opam/master/shell/install.sh) --version 2.2.0~alpha3"
or download manually from the Github "Releases" page to your PATH.
-
Or from source, manually: see the instructions in the README.
You should then run:
opam init --reinit -ni
Please report any issues to the bug-tracker.
Thanks for trying this new release out, and we hope you will enjoy the new features!