use spack branch only if specified

Author: pramodk

tests/jenkins/Jenkinsfile

@@ -5,7 +5,7 @@ pipeline {
     parameters {
         string(name: 'sha1', defaultValue: 'master',
                description: 'What branch of CoreNeuron to test.')
-        string(name: 'SPACK_BRANCH', defaultValue: 'develop',
+        string(name: 'SPACK_BRANCH', defaultValue: '',
                description: 'Which branch of spack to use.')
         string(name: 'NEURON_BRANCH', defaultValue: '',
                description: 'Which branch of neuron to use. For master branch (neuron@develop) leave this parameter blank.')

tests/jenkins/spack_setup.sh

@@ -18,8 +18,15 @@ install_spack() (
     SPACK_REPO=https://github.com/BlueBrain/spack.git
     SPACK_BRANCH=${SPACK_BRANCH:-"develop"}
 
-    echo "Installing SPACK. Cloning $SPACK_REPO $SPACK_ROOT --depth 1 -b $SPACK_BRANCH"
-    git clone $SPACK_REPO $SPACK_ROOT --depth 1 -b $SPACK_BRANCH
+    # cloning branch option
+    BRANCH_OPT=""
+    if [ -n "$SPACK_BRANCH" ]; then
+        BRANCH_OPT="-b ${SPACK_BRANCH}"
+    fi
+
+    echo "Installing SPACK. Cloning $SPACK_REPO $SPACK_ROOT --depth 1 $BRANCH_OPT"
+    git clone $SPACK_REPO $SPACK_ROOT --depth 1 $BRANCH_OPT
+
     # Use BBP configs
     mkdir -p $SPACK_ROOT/etc/spack/defaults/linux
     cp /gpfs/bbp.cscs.ch/apps/hpc/jenkins/config/*.yaml $SPACK_ROOT/etc/spack/