Now that there is an ocamlbuild package in opam it should be listed in the generated opam file.

Running oasis2opam on debian-formats generates this version constraint which is not satisfiable on OCaml 4.01+: ("mikmatch" {= "1.0.6"} | "mikmatch" {= "1.0.5"})

However the original _oasis file didn't have a version constraint, apparently this is because versions higher than 1.0.6 of mikmatch have pcre as a depopts, so I think that oasis2opam should in this case generate this: "mikmatch" "pcre"

$ oasis2opam --query mikmatch_pcre
"mikmatch_pcre" is provided by: ("mikmatch" {= "1.0.6"} | "mikmatch" {= "1.0.5"})
$ opam install mikmatch.1.0.6
[ERROR] mikmatch.1.0.6 is not available because it requires OCaml >= 4.00 & < 4.01.
$ opam install mikmatch.1.0.5
[ERROR] mikmatch.1.0.5 is not available because it requires OCaml < 4.01.
$ opam info mikmatch
             package: mikmatch
             version: 1.0.8
          repository: default
        upstream-url: https://github.com/mjambon/mikmatch/archive/v1.0.8.tar.gz
       upstream-kind: http
   upstream-checksum: 0f3b272491bff4fe842948dbf71d022e
            homepage: http://mjambon.com/micmatch.html
                 doc: http://mjambon.com/mikmatch-manual.html
             depends: ocamlfind & camlp4 & tophide >= 1.0.2
             depopts: pcre
   installed-version: 1.0.8 [system 4.02.1 4.02.0+trunk]
  available-versions: 1.0.5, 1.0.6, 1.0.7, 1.0.8
         description: OCaml syntax extension for regexps

Workaround:

oasis2opam --local
sed -i -e 's/("mikmatch".*/("mikmatch" "pcre")/' opam/opam

It seems that, if a BuildDepends entry appears in an Executable but not in a Library, it is not included in the opam file. For instance, my project includes a single library with the following BuildDepends:

  BuildDepends:
    batteries,
    monadlib,
    ocaml-monadic,
    ppx_deriving.std (>= 2.0),
    yojson

It has a single executable with this BuildDepends:

  BuildDepends:
    batteries,
    jhupllib,
    oUnit,
    ppx_deriving.std (>= 2.0),
    ppx_deriving_yojson

The resulting opam file contains this depends entry:

depends: [
  "base-threads"
  "batteries"
  "monadlib"
  "oasis" {build & >= "0.4.7"}
  "ocaml-monadic"
  "ocamlbuild" {build}
  "ocamlfind" {build}
  "ounit" {build}
  "ppx_deriving" {>= "2.0"}
  "yojson"
]

As a result, the OPAM package fails to install unless the user has already manually installed ppx_deriving_yojson. Am I misunderstanding the function of these fields? Is this an oversight?

The above project can be found here. Steps to reproduce:

mkdir -p ztemp
cd ztemp
export OPAMROOT="$(pwd)/opam"
mkdir -p $OPAMROOT
opam init
eval `opam config env`
git clone https://github.com/JHU-PL-Lab/jhu-pl-lib.git
cd jhu-pl-lib
git checkout c901c56ea93640e5aaa0232e6b05000e5f87120b
opam pin add jhupllib .

The last command will fail with an error message something like this:

#=== ERROR while installing jhupllib.0.1+dev ==================================#
# opam-version 1.2.2
# os           linux
# command      ocaml setup.ml -configure --prefix /home/zpalmer/ztemp/opam/4.04.1
# path         /home/zpalmer/ztemp/opam/4.04.1/build/jhupllib.0.1+dev
# compiler     4.04.1
# exit-code    1
# env-file     /home/zpalmer/ztemp/opam/4.04.1/build/jhupllib.0.1+dev/jhupllib-4107-aaa640.env
# stdout-file  /home/zpalmer/ztemp/opam/4.04.1/build/jhupllib.0.1+dev/jhupllib-4107-aaa640.out
# stderr-file  /home/zpalmer/ztemp/opam/4.04.1/build/jhupllib.0.1+dev/jhupllib-4107-aaa640.err
### stderr ###
# ocamlfind: Package `ppx_deriving_yojson' not found

Please let me know if I can provide additional information. Thank you for the tool!

When trying to generate an OPAM package for OASIS itself, I got a very ocamlbuild dependency:

$ oasis2opam --query ocamlbuild
"ocamlbuild" is provided by: ("ocamlbuild" {= "0.9.3"} | "ocamlbuild" {= "0.9.2"} | "ocamlbuild" {= "0.9.1"} | "ocamlbuild" {= "0.9.0"} | "ocamlbuild" {= "0"})

@Chris00 why the package doesn't simply depend on ocamlbuild?

After an opam update && opam upgrade this morning it looks like there is a change in oasis which breaks oasis2opam. The opam output is pasted below.

===== ERROR while recompiling oasis2opam.0.3.6 =====
# opam-version 1.1.1
# os           linux
# command      ocaml setup.ml -build
# path         /home/hcarty/.opam/4.01.0/build/oasis2opam.0.3.6
# compiler     4.01.0
# exit-code    1
# env-file     /home/hcarty/.opam/4.01.0/build/oasis2opam.0.3.6/oasis2opam-7428-ad6566.env
# stdout-file  /home/hcarty/.opam/4.01.0/build/oasis2opam.0.3.6/oasis2opam-7428-ad6566.out
# stderr-file  /home/hcarty/.opam/4.01.0/build/oasis2opam.0.3.6/oasis2opam-7428-ad6566.err
### stdout ###
# ...[truncated]
# /home/hcarty/.opam/4.01.0/bin/ocamlfind ocamlc -c -g -annot -package oasis -package str -package unix -I src -o src/BuildDepends.cmo src/BuildDepends.ml
# /home/hcarty/.opam/4.01.0/bin/ocamlfind ocamlc -c -g -annot -package oasis -package str -package unix -I src -o src/oasis2opam.cmo src/oasis2opam.ml
# + /home/hcarty/.opam/4.01.0/bin/ocamlfind ocamlc -c -g -annot -package oasis -package str -package unix -I src -o src/oasis2opam.cmo src/oasis2opam.ml
# File "src/oasis2opam.ml", line 83, characters 22-467:
# Warning 8: this pattern-matching is not exhaustive.
# Here is an example of a value that is not matched:
# Object (_, _, _)
# File "src/oasis2opam.ml", line 237, characters 32-49:
# Error: Unbound value OASISContext.args
# Command exited with code 2.
### stderr ###
# fatal: Not a git repository (or any of the parent directories): .git
# fatal: Not a git repository (or any of the parent directories): .git
# E: Failure("Command ''/home/hcarty/.opam/4.01.0/bin/ocamlbuild' src/oasis2opam.native -tag debug' terminated with error code 10")

opam lint warns that there is no remove field when _oasis only builds an executable:
warning 27: No field 'remove' while a field 'install' is present, uncomplete uninstallation suspected

I thought that in this case the install field could be removed too and just rely on the generated .install file, however that file only contains the bin section.
For example for this _oasis file oasis2opam --local doesn't generate the sbin,etc or doc sections in the .install file:

-sbin: [
-  "libres3/_build/src/server/libres3_setup.native" {"libres3_setup"}
-  "libres3/_build/src/server/libres3_report.native" {"libres3_report"}
-  "libres3/_build/src/ocsigen/libres3_ocsigen.native" {"libres3_ocsigen"}
-  "libres3/src/files/sbin/libres3_certgen"
-  "libres3/src/files/sbin/libres3"
-  "libres3/src/files/sbin/libres3_env.sh"
-]
-etc: [
-  "libres3/src/files/conf/libres3.sample.s3cfg"
-  "libres3/src/files/conf/libres3-insecure.sample.s3cfg"
-  "libres3/src/files/conf/mime.types"
-]
-doc: [
-  "libres3/README"
-  "libres3/src/files/s3genlink.py"
-  "libres3/doc/manual/manual.pdf"
+bin: [
+  "?_build/src/server/libres3_report.byte" {"libres3_report"}
+  "?_build/src/server/libres3_report.native" {"libres3_report"}
+  "?_build/src/server/libres3_setup.byte" {"libres3_setup"}
+  "?_build/src/server/libres3_setup.native" {"libres3_setup"}
+  "?_build/src/ocsigen/libres3_ocsigen.byte" {"libres3_ocsigen"}
+  "?_build/src/ocsigen/libres3_ocsigen.native" {"libres3_ocsigen"}

This is a note to check that oasis installs Changes* to docdir. If not, oasis2opam could add the line iff a Changes* file exists.

Camelus now tags missing homepage as an error:

error 35: Missing field 'homepage'

oasis2opam should do the same at an earlier stage.

On my system, the code returned here is not 66 (it's 1).
I'm not sure if it's specific or not.

Pre-emptive bug, I don't yet have the issue.

I see in commit 77b07e3, that you have removed the generation of oasis_remove.ml (which is a good thing).

The problem is that '-C' is only fixed with OASIS 0.4.7 and you may have a setup.ml generated with former version (e.g. 0.4.6).

Can you check the version of OASIS used to generate setup.ml and issue an error if < 0.4.7 ?

To check the version

$ ocaml setup.ml -version

These files were in opam/files/ previously and now they are created in the project root with oasis2opam 0.7.

Related to #14, running oasis2opam on debian-formats generates a depopts on oUnit, but the _oasis file doesn't contain a flag to disable building the tests, so it should be a regular dependency, otherwise opam install fails:

Executable test
  Path:       test
  MainIs:     test.ml
  Install:    false
  BuildDepends: debian-formats, oUnit

Workaround: manually move ounit from depopts to depends.

I don't have direct access to the error, but it is a type mismatch on line 35 of oasis2opam.ml.

This expression has type OASISText.t = OASISText.elt list
but an expression was expected of type string

Just a very minor comment:

For the depends field, I quite like to have one dependency per line (it makes clearer to which package the version contraints, if any, belongs to). Would it be possible to change that ?

The latest oasis2opam can generate correct conflicts field for most situations (when only a single version comparison is used), but if the version constraint is a conjunction then opam doesn't accept the generated constraint.

I'll send a new PR once I've clarified the behaviour in opam

oasis2opam is tightly linked to OASIS and we should make sure it is always in sync with oasis. One way to achieve that, is to make it a plugin of OASIS. In this case we will be sure that the parsing of _oasis files is up to date.

I have been hit by this bug a few time, because oasis2opam was using an old parser from OASIS that didn't handled some special features (like AlphaFeatures and BetaFeatures introduced recently).

While testing #22 I came across a bug where depopts are no longer being quoted. Where as previously they would be generated like this:

depopts: [
  "js_of_ocaml"
]

they are now being generated like this:

depopts: [
  js_of_ocaml
]

513bdbe seems to be the culprit.

When I use the tools with an archive containing the following _oasis file, I
get :

Fatal error: exception Failure("Feature stdfiles_markdown doesn't exist.")

The _oasis file :

OASISFormat: 0.4
Name:        OcLaunch
Version:     0.1.2
Synopsis:    Launch commands automatically
Authors:     Joly Clément <[email protected]>
Maintainers: Joly Clément <[email protected]>
License:     CeCILL
LicenseFile: LICENSE
Copyrights: (C) 2014 Joly Clément
Homepage: http://www.oclaunch.tuxfamily.org
BuildTools: ocamlbuild, camlp4o
Plugins: StdFiles (0.4), DevFiles (0.4)
XStdFilesREADME: true
XStdFilesINSTALL: true
XStdFilesAUTHORS: true
AlphaFeatures: stdfiles_markdown, compiled_setup_ml
Description: OcLaunch is a command-line tool to launch successively (each time the program is called) commands. It is designed to be used with any program, interactive or not. This a early version. Feedback is welcomed at [email protected].

PreBuildCommand: atdgen -t ./src/settings.atd
PreBuildCommand: atdgen -j ./src/settings.atd
PreBuildCommand: atdgen -v ./src/settings.atd

Executable oclaunch
  Path:       src
  MainIs:     oclaunch.ml
  BuildDepends: core, yojson, atdgen, threads, core_extended
  CompiledObject: byte

The _oasis file is of course working with oasis

Latest version fails to install from OPAM, apparently due to regenerating the setup.ml file:

$ cat /home/edwin/.opam/4.00.1/build/oasis2opam.0.3.3/oasis2opam-10604-865888.err
File "setup.ml", line 1:
Error: Reference to undefined global `Unix'

If I clone this upstream repository everything works fine, unless I run 'oasis setup', which then fails the same as above due to the use of 'Unix.gettimeofday' in setup.ml.
Would it be possible to move this to myocamlbuild.ml where the Unix (well Ocamlbuild_pack.My_unix) module is available?

Forking the discussion on #29

For .install, the OPAM manual indeed [talks about that file] (https://opam.ocaml.org/doc/Manual.html#packagenameinstall) without expressing a clear preference. A discussion — somewhere on Github I think — made clear however that <pkg>.install files are not welcome in the opam-repository in order not to "pollute" everybody with extra files that may not be useful for them.

Not sure to understand where the .install should be ?

1. in the upstream source?
   I don't see the use of it in there. Except for OPAM, it won't be useful (hence polluting the source).
2. in the OPAM repository?
   I thought it was a good option. If you can point me to the right place for the mentioned discussion. that would be nice.

When this kind of situations occurs, oasis2opam should refuse to create the OPAM package (which will not behave as expected).

It would be nice to have a "local" mode that output only an opam file, given an _oasis one (no need for a tarball, etc). This would especially fit the new opam feature where you can pin an unknown package, as long as there is an opam file a the root of the project.

I used oasis2opam for my usbmux project but stumbled on this bug at the worst moment, when a user had reported it when I was debugging a different issue with them!

$ opam pin add usbmux https://github.com/fxfactorial/ocaml-usbmux -y

and it blows up with:

[usbmux] https://github.com/fxfactorial/ocaml-usbmux downloaded

usbmux needs to be installed.
The following actions will be performed:
∗ install usbmux 1.3.1*

=-=- Gathering sources =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
[usbmux.1.3.1] https://github.com/fxfactorial/ocaml-usbmux downloaded

=-=- Processing actions -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
[ERROR] The compilation of usbmux failed at "oasis setup".
Processing 1/1: [usbmux: ocaml]
#=== ERROR while installing usbmux.1.3.1 ======================================#

full thread here:
onlinemediagroup/ocaml-usbmux#6 (comment)

I'm not sure if this is opam's fault, oasis's fault or oasis2opam.

Right now oasis2opam uses whatever source repository is available, like this one:

SourceRepository head
  Type: git
  Location: git://github.com/ocaml/oasis.git
  Browser: https://github.com/ocaml/oasis

I think it would be better to differentiate between head and opam-pin, by introducing another source repository with a different name:

SourceRepository opam-pin
  Type: git
  Location: git://github.com/ocaml/oasis.git
  Branch: opam/testing

If not defined, we can fallback to the default behavior.

oasis2opam generated the following dependency :

 ("oasis" {>= "0.4.4"} | "oasis" {= "0.4.3"} | "oasis" {= "0.4.2"} | "oasis" {= "0.4.1"} | "oasis" {= "0.4.0"} | "oasis" {= "0.3.0"} | "oasis-mirage")

However, I have in my _oasis file :

OASISFormat: 0.4

oasis 0.3.0 shouldn't be present.

opam lint complains about several issues on files generated by oasis2opam. E.g. with Lacaml:

Validation failed for ~/archive/github/mmottl/forked/opam-repository/packages/lacaml/lacaml.7.2.1/opam:
  - Field 'ocaml-version' is deprecated, use 'available' instead
  - Missing field 'bug-reports'
  - Package declares 'depexts', but has no 'post-messages' to help the user out when they are missing

If I have in my _oasis

AlphaFeatures: ocamlbuild_more_args

oasis2opam errors with :

Fatal error: exception Failure("Feature ocamlbuild_more_args doesn't exist.")

The SourceRepository is pretty generic and Camelus enforces a stricter check:

error 42: The 'dev-repo' field doesn't specify an explicit VCS. You may use
URLs of the form "git+https://" or a ".hg" or ".git" suffix

It would be nice to have this check earlier in the process.

See ocaml/opam-repository#8031

I have the following in my _oasis:

Flag quickstart_tests                                                           
  Description: Build test-quickstart                                            
  Default: true   

[...]

Executable "test-quickstart"                                                    
  Path: test/test-quickstart                                                    
  MainIs: TestQuickstart.ml                                                     
  Install: false                                                                
  CompiledObject: best                                                          
  Build$: flag(tests) && flag(quickstart_tests)                                 
  BuildDepends: oUnit (>= 2.0.0), findlib, fileutils (>= 0.4.2),                
                expect.pcre (>= 0.0.4), oasis, oasis.builtin-plugins,           
                test-common 

The generated opam:

build-test: [
  ["ocaml" "setup.ml" "-configure" "--enable-tests"]
  ["ocaml" "setup.ml" "-build"]
  ["ocaml" "setup.ml" "-test"]
]
build-doc: [ "ocaml" "setup.ml" "-doc" ]
depends: [
  "base-unix"
  "camlp4" {test}
  "fileutils" {test & >= "0.4.2"}
  "ocamlbuild"
  "ocamlfind" {>= "1.3.1"}
  "ocamlify" {build}
  "ocamlmod" {build}
  "omake" {test}
  "ounit" {test & >= "2.0.0"}
  "pcre" {test}
]
depopts: [
  "benchmark"
  "expect"
]
conflicts: [
  "benchmark" {< "1.2"}
  "expect" {< "0.0.4"}
  "oasis-mirage" {= "0.3.0"}
  "oasis-mirage" {= "0.3.0a"}
]

And the following error when building:

# ocamlfind: Package `expect.pcre' not found
# W: Field 'pkg_expect_pcre' is not set: Command ''/home/travis/.opam/4.03.0/bin/ocamlfind' query -format %d expect.pcre > '/tmp/oasis-402383.txt'' terminated with error code 2
# E: Cannot find findlib package expect.pcre (>= 0.0.4)
# E: Failure("1 configuration error")

What I expect is to have either:

• build-test to disable quickstart-tests:

build-test: [
  ["ocaml" "setup.ml" "-configure" "--enable-tests" "--disable-quickstart-tests"]
  ["ocaml" "setup.ml" "-build"]
  ["ocaml" "setup.ml" "-test"]
]

• OR take into account default value of the flag and update depends/depopts/conflicts accordingly:

depends: [
  "base-unix"
  "camlp4" {test}
  "fileutils" {test & >= "0.4.2"}
  "ocamlbuild"
  "ocamlfind" {>= "1.3.1"}
  "ocamlify" {build}
  "ocamlmod" {build}
  "omake" {test}
  "ounit" {test & >= "2.0.0"}
  "pcre" {test}
  "expect" {test & >= "0.0.4"}
]
depopts: [
  "benchmark"
]
conflicts: [
  "benchmark" {< "1.2"}
  "oasis-mirage" {= "0.3.0"}
  "oasis-mirage" {= "0.3.0a"}
]

I've invoked oasis2opam on a package containing OCamlVersion: >= 4.02, and it generated a field ocaml-version: [ (>= "4.01") & (>= "4.02") ], which is rejected by opam 1.1.1.

package.install:

etc: [
  "setup.ml"
  "setup.data"
  "setup.log"
  "_oasis_remove_.ml"
]

and

_oasis_remove_.ml:

open Printf

let () =
  let dir = Sys.argv.(1) in
  (try Sys.chdir dir
   with _ -> eprintf "Cannot change directory to %s\n%!" dir);
  exit (Sys.command "ocaml setup.ml -uninstall")

get added to every version of every package that uses this tool and are distributed to every user of opam even if they don't use those packages. They are always the same. They increase bandwidth and storage costs with very little benefit. They belong in the build system of the package. They make opam package analysis harder because the package is no longer self-contained.

Perhaps the solution is to upstream oasis changes so setup.ml can change its own directory?