Print warning if notify-send is a missing dependency

auto-notify.plugin.zsh

@@ -122,4 +122,12 @@ function enable_auto_notify() {
 }
 
 _auto_notify_reset_tracking
-enable_auto_notify
+
+
+platform="$(uname)"
+if [[ "$platform" == "Linux" ]] && ! type notify-send > /dev/null; then
+    printf "'notify-send' must be installed for zsh-auto-notify to work\n"
+    printf "Please install it with your relevant package manager\n"
+else
+    enable_auto_notify
+fi

tests/test_plugin.zunit

@@ -1,23 +1,57 @@
 #!/usr/bin/env zunit
 
 @setup {
-    load "../auto-notify.plugin.zsh"
+    function uname {
+        printf "Linux"
+    }
+    # Mock function for passing builds where we don't
+    # really need notify-send to be installed (e.g. Mac OSX)
+    function notify-send {
+    }
 }
 
 @test 'version exported' {
     git_version="$(git tag --list | sort -V | tail -1)"
     git tag --list
 
+    load "../auto-notify.plugin.zsh"
+
     assert "$AUTO_NOTIFY_VERSION" is_not_empty
     assert "$AUTO_NOTIFY_VERSION" same_as "$git_version"
 }
 
+@test 'print warning if notify-send is not installed' {
+    function type {
+        return 1
+    }
+
+    run load "../auto-notify.plugin.zsh"
+
+    assert "$lines[1]" same_as "'notify-send' must be installed for zsh-auto-notify to work"
+    assert "$lines[2]" same_as "Please install it with your relevant package manager"
+
+@test 'dont load auto-notify if notify-send is not installed' {
+    function type {
+        return 1
+    }
+
+    load "../auto-notify.plugin.zsh"
+
+    assert "_auto_notify_track" not_in $preexec_functions
+    assert "_auto_notify_send" not_in $precmd_functions
+}
+
+
 @test 'hook functions are loaded by default' {
+    load "../auto-notify.plugin.zsh"
+
     assert '_auto_notify_track' in $preexec_functions
     assert '_auto_notify_send' in $precmd_functions
 }
 
 @test 'enable/disable auto-notify' {
+    load "../auto-notify.plugin.zsh"
+
     disable_auto_notify
     assert '_auto_notify_track' not_in $preexec_functions
     assert '_auto_notify_send' not_in $precmd_functions