Rollback to fetch failure

[rjbou]

• If all action error are fetching failure, return code 31 (Sync_error) instead of code 40 (Package_operation_error).
• if there is mixed failures, exit with code 40
• if there is some sucess, and some fetching failures, exit with code 31

Fix #4214

[rjbou]

ping @kit-ty-kate

[kit-ty-kate]

Mh, I just tried and it still didn't give me the right exit code:

$ opam install kappa-library.4.1.0
The following actions will be performed:
  ∗ install kappa-library 4.1.0

<><> Processing actions <><><><><><><><><><><><><><><><><><><><><><><><><><><><>
[ERROR] Failed to get sources of kappa-library.4.1.0: Bad checksum

#=== ERROR while fetching sources for kappa-library.4.1.0 ====================#
https://github.com/Kappa-Dev/KappaTools/archive/v4.1.tar.gz (Bad checksum, expected sha256=f24a38f73a88f1b3d8137aa083bad8d76c679c4b6c59ec29e1567ad95bf1df13)


<><> Error report ><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><>
┌─ The following actions failed
│ ⬇ fetch kappa-library 4.1.0
└─ 
╶─ No changes have been performed
$ echo $?
31

[rjbou]

hmm... I don't have the same locally :

$ ./opam install kappa-library.4.1.0
The following actions will be performed:
  ∗ install fmt           0.8.9 [required by kappa-library]
  ∗ install num           1.4   [required by kappa-library]
  ∗ install logs          0.7.0 [required by kappa-library]
  ∗ install kappa-library 4.1.0
===== ∗ 4 =====
Do you want to continue? [Y/n] y

<><> Processing actions <><><><><><><><><><><><><><><><><><><><><><><><><><><><>
⬇ retrieved fmt.0.8.9  (cached)
⬇ retrieved logs.0.7.0  (cached)
⬇ retrieved num.1.4  (cached)
∗ installed fmt.0.8.9
∗ installed num.1.4
∗ installed logs.0.7.0
[ERROR] Failed to get sources of kappa-library.4.1.0: Bad checksum

#=== ERROR while fetching sources for kappa-library.4.1.0 =====================#
OpamSolution.Fetch_fail("https://github.com/Kappa-Dev/KappaTools/archive/v4.1.tar.gz (Bad checksum, expected sha256=f24a38f73a88f1b3d8137aa083bad8d76c679c4b6c59ec29e1567ad95bf1df13)")


<><> Error report <><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><>
┌─ The following actions failed
│ ⬇ fetch kappa-library 4.1.0
└─ 
┌─ The following changes have been performed
│ ∗ install fmt  0.8.9
│ ∗ install logs 0.7.0
│ ∗ install num  1.4
└─ 

The former state can be restored with:
    opam/_build/default/src/client/opamMain.exe switch import ".opam/switch/.opam-switch/backup/state-20201203142116.export"
Or you can retry to install your package selection with:
    opam/_build/default/src/client/opamMain.exe install --restore

==> err code [40]


$ ./opam install kappa-library.4.1.0
The following actions will be performed:
  ∗ install kappa-library 4.1.0

<><> Processing actions <><><><><><><><><><><><><><><><><><><><><><><><><><><><>
[ERROR] Failed to get sources of kappa-library.4.1.0: Bad checksum

#=== ERROR while fetching sources for kappa-library.4.1.0 =====================#
OpamSolution.Fetch_fail("https://github.com/Kappa-Dev/KappaTools/archive/v4.1.tar.gz (Bad checksum, expected sha256=f24a38f73a88f1b3d8137aa083bad8d76c679c4b6c59ec29e1567ad95bf1df13)")


<><> Error report <><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><>
┌─ The following actions failed
│ ⬇ fetch kappa-library 4.1.0
└─ 
╶─ No changes have been performed

==> err code [40]


$ ./opam install kappa-library.4.1.0 pat-sub #pat-sub is a fail on build local package

<><> Synchronising pinned packages ><><><><><><><><><><><><><><><><><><><><><><>
[pat-sub.0.1] synchronised (file://pat-sub)
[WARNING] Failed checks in opam file from upstream of pat-sub:
  warning 62: License doesn't adhere to the SPDX standard, see https://spdx.org/licenses/: " "
[pat-sub] Installing new package description from upstream file:///w/pkgs_opam/pat-sub

The following actions will be performed:
  ∗ install kappa-library 4.1.0
  ∗ install pat-sub       0.1*
===== ∗ 2 =====

<><> Processing actions <><><><><><><><><><><><><><><><><><><><><><><><><><><><>
[ERROR] The compilation of pat-sub.0.1 failed at "bcat foo bar baz".
[ERROR] Failed to get sources of kappa-library.4.1.0: Bad checksum

#=== ERROR while compiling pat-sub.0.1 ========================================#
# context     2.1.0~beta4 | linux/x86_64 |  | pinned(file:///w/pkgs_opam/pat-sub)
# path        ~/.opam/switch/.opam-switch/build/pat-sub.0.1
# command     ~/.opam/opam-init/hooks/sandbox.sh build bcat foo bar baz
# exit-code   1
# env-file    ~/.opam/log/pat-sub-2545285-9b2e35.env
# output-file ~/.opam/log/pat-sub-2545285-9b2e35.out
### output ###
# bwrap: execvp bcat: No such file or directory


#=== ERROR while fetching sources for kappa-library.4.1.0 =====================#
OpamSolution.Fetch_fail("https://github.com/Kappa-Dev/KappaTools/archive/v4.1.tar.gz (Bad checksum, expected sha256=f24a38f73a88f1b3d8137aa083bad8d76c679c4b6c59ec29e1567ad95bf1df13)")


<><> Error report <><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><>
┌─ The following actions failed
│ ⬇ fetch kappa-library 4.1.0
│ λ build pat-sub       0.1
└─ 
╶─ No changes have been performed

==> err code: [31]