test: dune exec for absolute directories

Signed-off-by: Ali Caglayan <[email protected]>

Author: Alizter

test/blackbox-tests/test-cases/exec/exec-abs.t

@@ -0,0 +1,24 @@
+Testing interaction of dune exec and absolute directories.
+
+  $ cat > dune-project <<EOF
+  > (lang dune 3.20)
+  > EOF
+
+  $ cat > dune <<EOF
+  > (executable
+  >  (name foo))
+  > EOF
+
+  $ cat > foo.ml <<EOF
+  > let () = print_endline "hi" ;;
+  > EOF
+
+  $ dune exec ./foo.exe
+  hi
+
+  $ dune exec $PWD/foo.exe
+  Error: Program
+  '$TESTCASE_ROOT/foo.exe'
+  not found!
+  [1]
+