feat(setup/rebuild): use OPAMs prefix if possible

.utils/rebuild.sh

@@ -42,11 +42,12 @@ ocaml () {
     CURRENT="ocaml"
     dune build $([ -z $DUNEJOBS ] || echo "-j $DUNEJOBS")
     CURRENT="ocaml/install"
+
     # Small hack for those that are not using [opam] at all: by
     # default install OCaml binaries in `~/.cargo` (which is supposed
     # to be in PATH anyway).
-    DUNE_INSTALL_PREFIX="${DUNE_INSTALL_PREFIX:-$HOME/.cargo}"
-    dune install --profile dev --prefix $DUNE_INSTALL_PREFIX
+    INSTALL_PREFIX="${OPAM_SWITCH_PREFIX:-${DUNE_INSTALL_PREFIX:-$HOME/.cargo}}"
+    dune install --profile dev --prefix $INSTALL_PREFIX
 
     if ( command -v "which" && command -v "sort" && command -v "wc" ) >/dev/null; then
         case $(which -a hax-engine | sort -u | wc -l) in

setup.sh

@@ -2,7 +2,9 @@
 
 set -eu
 
-opam_jobs=2
+SCRIPTPATH="$( cd -- "$(dirname "$0")" >/dev/null 2>&1 ; pwd -P )"
+
+opam_jobs=4
 
 # Parse command line arguments.
 all_args=("$@")
@@ -16,6 +18,17 @@ while [ $# -gt 0 ]; do
     shift
 done
 
+# Warns if we're building in a dirty checkout of hax: while hacking on
+# hax, we should really be using the `./.utils/rebuild.sh`
+warn_if_dirty() {
+    (
+        cd "$SCRIPTPATH"
+        if ! git diff-index --quiet HEAD -- >& /dev/null; then
+            printf '\e[33mWarning: This is a dirty checkout of hax!\n         If you are hacking on hax, please use the \e[1m`./.utils/rebuild.sh`\e[0m\e[33m script.\e[0m\n\n'
+        fi
+    )
+}
+
 # Ensures a given binary is available in PATH
 ensure_binary_available() {
     command -v "$1" >/dev/null 2>&1 || {
@@ -73,6 +86,8 @@ install_ocaml_engine() {
     )
 }
 
+warn_if_dirty
+
 for binary in opam node rustup jq; do
     ensure_binary_available $binary
 done