Complain on non-existing exercises

Author: mquinson

Makefile

@@ -31,9 +31,8 @@ docker: all
 	rm -rf dockersite && cp -r site dockersite	
 	for f in `find dockersite -name '*setup.sh'`; do echo "Changing location of shtrl-check in $$f"; sed -i 's|usr/lib/shutorial/bin|shutorial/bin|' $$f; chmod +rx $$f; done
 	cp distros/Docker/shutorial.sh dockersite/
-	docker build -t shutorial -f distros/Docker/Dockerfile dockersite
+	docker build -t mquinson/shutorial -f distros/Docker/Dockerfile dockersite
 	rm -rf dockersite
-#	chmod +x shutorial
 
 install:
 	@echo "XX make install"

distros/Docker/shutorial.sh

@@ -13,7 +13,7 @@ login)
     # log into the docker
     exec bash
     ;;
-list)
+list|ls)
     echo "Here is the list of existing exercises:"
     sed 's/^/  /' /usr/share/shutorial/usage/exercises.list
     echo
@@ -35,6 +35,12 @@ run)
 
     user=$(id -un)
 
+    if [ ! -e "/usr/share/shutorial/usage/$exo/" ]; then
+        echo "There is no exercise $exo in the list. To see the current list,  simply type:"
+        echo "  shutorial list"
+        exit 1
+    fi
+    
     echo "Launching exercice $exo"
 
     # Tell the user what to do on login