fix checking whether the repos already exist

prepare-opam.sh

@@ -44,19 +44,19 @@ eval `opam conf env`
 
 # Make sure we got the right set of repositories registered.
 # By default, they are added with rank 1, i.e. at the top of the list. So we add them with increasing priority.
-test -d "$OPAMROOT/repo/coq-released" || run opam repo add coq-released https://coq.inria.fr/opam/released
+test -f "$OPAMROOT/repo/coq-released.tar.gz" || run opam repo -a add coq-released https://coq.inria.fr/opam/released
 if echo "$@" | egrep "\b(dev|beta|rc)" > /dev/null; then
     # We are compiling against a dev version of something. Get ourselves the dev repositories.
     status "[prepare-opam] adding Coq dev repositories"
-    run opam repo -a add coq-extra-dev https://coq.inria.fr/opam/extra-dev
-    run opam repo -a add coq-core-dev https://coq.inria.fr/opam/core-dev
+    test -f "$OPAMROOT/repo/coq-extra-dev.tar.gz" || run opam repo -a add coq-extra-dev https://coq.inria.fr/opam/extra-dev
+    test -f "$OPAMROOT/repo/coq-core-dev.tar.gz" || run opam repo -a add coq-core-dev https://coq.inria.fr/opam/core-dev
 else
     # No dev version, make sure we do not have the dev repositories.
     status "[prepare-opam] removing Coq dev repositories"
     run opam repo -a remove coq-extra-dev
     run opam repo -a remove coq-core-dev
 fi
-test -d "$OPAMROOT/repo/iris-dev" || run opam repo add iris-dev git+https://gitlab.mpi-sws.org/iris/opam.git
+test -f "$OPAMROOT/repo/iris-dev.tar.gz" || run opam repo -a add iris-dev git+https://gitlab.mpi-sws.org/iris/opam.git
 run opam repo prio iris-dev 1 # make sure this stays at the top
 echo