install-sharness.sh: implement updates

We want to be able to update Sharness to benefit from
new features.

License: MIT
Signed-off-by: Christian Couder <chriscool@tuxfamily.org>

test/sharness/lib/install-sharness.sh

@@ -11,16 +11,37 @@ urlprefix=https://github.com/mlafeldt/sharness.git
 clonedir=lib
 sharnessdir=sharness
 
+if test -f "$clonedir/$sharnessdir/SHARNESS_VERSION_$version"
+then
+    # There is the right version file. Great, we are done!
+    exit 0
+fi
+
 die() {
-  echo >&2 "$@"
-  exit 1
+    echo >&2 "$@"
+    exit 1
 }
 
-mkdir -p "$clonedir" || die "Could not create '$clonedir' directory"
-cd "$clonedir" || die "Could not cd into '$clonedir' directory"
+checkout_version() {
+    git checkout "$version" || die "Could not checkout '$version'"
+    rm -f SHARNESS_VERSION_* || die "Could not remove 'SHARNESS_VERSION_*'"
+    touch "SHARNESS_VERSION_$version" || die "Could not create 'SHARNESS_VERSION_$version'"
+    echo "Sharness version $version is checked out!"
+}
 
-git clone "$urlprefix" || die "Could not clone '$urlprefix'"
-cd "$sharnessdir" || die "Could not cd into '$sharnessdir' directory"
-git checkout "$version" || die "Could not checkout '$version'"
+if test -d "$clonedir/$sharnessdir/.git"
+then
+    # We need to update sharness!
+    cd "$clonedir/$sharnessdir" || die "Could not cd into '$clonedir/$sharnessdir' directory"
+    git fetch || die "Could not fetch to update sharness"
+    checkout_version
+else
+    # We need to clone sharness!
+    mkdir -p "$clonedir" || die "Could not create '$clonedir' directory"
+    cd "$clonedir" || die "Could not cd into '$clonedir' directory"
 
+    git clone "$urlprefix" || die "Could not clone '$urlprefix'"
+    cd "$sharnessdir" || die "Could not cd into '$sharnessdir' directory"
+    checkout_version
+fi
 exit 0