Provide test case for testing the `noclobber` option from zsh

This tests the absence of the bug from #615

test/fast/Aliases/Running "nvm alias <aliasname> <target>" again should change the target

@@ -0,0 +1,21 @@
+#!/bin/sh
+
+. ../../../nvm.sh
+
+die () { echo $@ ; exit 1; }
+
+if [ -n "$ZSH_VERSION" ]; then
+  # set clobber option in order to test that this does not produce any
+  # incompatibilities
+  setopt noclobber
+fi
+
+nvm alias test-stable-1 0.0.2
+
+nvm alias test-stable-1 | \grep -e "test-stable-1 -> 0.0.2 (-> v0.0.2)" \
+  || die "nvm alias test-stable-1 0.0.2 did not set test-stable-1 to 0.0.2"
+
+nvm alias test-stable-1 0.0.1
+
+nvm alias test-stable-1 | \grep -e "test-stable-1 -> 0.0.1 (-> v0.0.1)" \
+  || die "nvm alias test-stable-1 0.0.1 did not set test-stable-1 to 0.0.1"