[ci] nix: pin batsim rather than use stable

ci/batsim-pinned.json

+{
+  "url": "https://framagit.org/batsim/batsim.git",
+  "rev": "6cdcd274c31fb11dfed03f2409f059b11c74a4f1",
+  "date": "2018-07-11T15:59:48+02:00",
+  "sha256": "1a0knfi935xw84g2lfn1s9fsnyvg00nygdqyyp5mird47gj8c72a",
+  "fetchSubmodules": true
+}

ci/default.nix

@@ -12,22 +12,22 @@ let
 
     # Redefine some packages for clarity's sake
     batexpe = kapack.batexpe;
-    batsim_stable = kapack.batsim;
+    batsim_pinned = kapack.batsim;
     batsim_dev = kapack.batsim_dev;
 
     # Packages defined in this tree
     batsched_local = callPackage ./local.nix {};
-    test_deps_stable = callPackage ./test-deps.nix {
-      batsim = batsim_stable;
+    test_deps_pinned = callPackage ./test-deps.nix {
+      batsim = batsim_pinned;
     };
     test_deps_dev = callPackage ./test-deps.nix {
       batsim = batsim_dev;
     };
 
     # Packages meant to be used as shells
-    test_stable = callPackage ./test-env.nix {
+    test_pinned = callPackage ./test-env.nix {
       batsched = batsched_local;
-      test_deps = test_deps_stable;
+      test_deps = test_deps_pinned;
     };
     test_dev = callPackage ./test-env.nix {
       batsched = batsched_local;

ci/pin-batsim.bash

+#!/usr/bin/env nix-shell
+#! nix-shell . -i bash -A test_deps_dev
+
+if [ "$#" -ne 1 ]; then
+    echo 'usage: pin-batsim.bash BATSIM-REV'
+    exit 1
+fi
+
+rev=$1
+nix-prefetch-git \
+    --url https://framagit.org/batsim/batsim.git \
+    --rev ${rev} \
+    > batsim-pinned.json

ci/test-deps.nix

 { stdenv, batsim, batexpe,
-  which, redis, procps, psmisc
+  which, redis, procps, psmisc,
+  nix-prefetch-git
 }:
 
 stdenv.mkDerivation rec {
@@ -8,5 +9,8 @@ stdenv.mkDerivation rec {
   # This package is not meant to be built
   unpackPhase = "true";
   installPhase = "true";
-  propagatedBuildInputs = [ batsim batexpe which redis procps psmisc ];
+  propagatedBuildInputs = [ batsim batexpe
+    which redis procps psmisc
+    nix-prefetch-git
+  ];
 }

ci/update-dependencies-cache.bash

@@ -3,5 +3,5 @@
 set -eu
 
 # (re)build up-to-date CI batsched package + deps, push them on binary cache
-nix-build ./ci -A test_stable | cachix push batsim
+nix-build ./ci -A test_pinned | cachix push batsim
 nix-build ./ci -A test_dev | cachix push batsim