diff --git a/test/common.sh b/test/common.sh
index 8162b8a..beadafa 100644
--- a/test/common.sh
+++ b/test/common.sh
@@ -29,8 +29,16 @@ make_fake_node() {
   VERSION="${1-}"
   [ -n "${VERSION}" ] || return 1
 
+  local FORMATTED_VERSION
+  FORMATTED_VERSION="$(nvm_format_version "${VERSION}")"
+
   local BIN_PATH
-  BIN_PATH="$(nvm_version_path "$(nvm_format_version "${VERSION}")")/bin"
+  BIN_PATH="$(nvm_version_path "${FORMATTED_VERSION}")/bin"
+  [ "${BIN_PATH}" != "/bin" ] || {
+    echo >&2 'nvm_version_path was empty'
+    return 5
+  }
+
   mkdir -p "${BIN_PATH}" || {
     echo >&2 'unable to make bin dir'
     return 2
@@ -40,6 +48,11 @@ make_fake_node() {
     echo >&2 'unable to make fake node bin'
     return 3
   }
+
+  nvm_is_version_installed "${FORMATTED_VERSION}" || {
+    echo >&2 'fake node is not installed'
+    return 4
+  }
 }
 
 make_fake_iojs() {
@@ -47,8 +60,16 @@ make_fake_iojs() {
   VERSION="${1-}"
   [ -n "${VERSION}" ] || return 1
 
+  local FORMATTED_VERSION
+  FORMATTED_VERSION="$(nvm_format_version "iojs-${VERSION}")"
+
   local BIN_PATH
-  BIN_PATH="$(nvm_version_path "$(nvm_format_version "iojs-${VERSION}")")/bin"
+  BIN_PATH="$(nvm_version_path "${FORMATTED_VERSION}")/bin"
+  [ "${BIN_PATH}" != "/bin" ] || {
+    echo >&2 'nvm_version_path was empty'
+    return 5
+  }
+
   mkdir -p "${BIN_PATH}" || {
     echo >&2 'unable to make bin dir'
     return 2
@@ -62,6 +83,11 @@ make_fake_iojs() {
     echo >&2 'unable to make fake iojs bin'
     return 3
   }
+
+  nvm_is_version_installed "${FORMATTED_VERSION}" || {
+    echo >&2 'fake iojs is not installed'
+    return 4
+  }
 }
 
 watch() {