diff --git a/package.json b/package.json
index d5ebb31..0e2fc67 100644
--- a/package.json
+++ b/package.json
@@ -9,9 +9,9 @@
     "test": "urchin test",
     "test/fast": "urchin -f test/fast",
     "test/slow": "urchin -f test/slow",
+    "test/install_script": "urchin -f test/install_script",
     "test/installation": "urchin -f test/installation",
-    "test/sourcing": "urchin -f test/sourcing",
-    "test/install_script": "urchin -f test/install_script"
+    "test/sourcing": "urchin -f test/sourcing"
   },
   "repository": {
     "type": "git",
diff --git a/test/install_script/nvm_do_install b/test/install_script/nvm_do_install
index 02c77f3..a969602 100755
--- a/test/install_script/nvm_do_install
+++ b/test/install_script/nvm_do_install
@@ -1,6 +1,9 @@
 #!/bin/sh
 
+die () { echo $@ ; exit 1; }
+
 NVM_ENV=testing . ../../install.sh
 
 #nvm_do_install is available
-type nvm_do_install > /dev/null 2>&1
+type nvm_do_install > /dev/null 2>&1 || die 'nvm_do_install is not available'
+
diff --git a/test/install_script/nvm_reset b/test/install_script/nvm_reset
index 25d9a34..4005d9c 100755
--- a/test/install_script/nvm_reset
+++ b/test/install_script/nvm_reset
@@ -1,21 +1,29 @@
 #!/bin/sh
 
+cleanup () {
+  unset -f safe_type
+}
+die () { echo $@ ; cleanup ; exit 1; }
+
 NVM_ENV=testing . ../../install.sh
 
 safe_type() {
-  type "$1" > /dev/null 2>&1 && return 0 || return 1
+  type "$1" > /dev/null 2>&1
 }
 
 # Check nvm_reset exists
-type nvm_reset > /dev/null 2>&1
+safe_type nvm_reset || die 'nvm_reset is not available'
 
 # Apply nvm_reset
 nvm_reset
 
 # The names should be unset
-! safe_type nvm_do_install && \
-  ! safe_type nvm_has && \
-  ! safe_type nvm_download && \
-  ! safe_type install_nvm_as_script && \
-  ! safe_type install_nvm_from_git && \
-  ! safe_type nvm_reset
+! safe_type nvm_do_install || die 'nvm_do_install is still available'
+! safe_type nvm_has || die 'nvm_has is still available'
+! safe_type nvm_download || die 'nvm_download is still available'
+! safe_type install_nvm_as_script || die 'install_nvm_as_script is still available'
+! safe_type install_nvm_from_git || die 'install_nvm_from_git is still available'
+! safe_type nvm_reset || die 'nvm_reset is still available'
+
+cleanup
+