From f4780d184dddbe3233fed77dac7ddeb74c4f5b02 Mon Sep 17 00:00:00 2001
From: Paul Oliver <puzza007@gmail.com>
Date: Tue, 19 Aug 2014 11:41:51 +0200
Subject: [PATCH] hope_list:unique_preserve_order/1 property test

---
 .gitignore               |  1 +
 Makefile                 | 14 ++++++++++++++
 rebar.config             |  5 +++++
 test/hope_list_SUITE.erl | 21 +++++++++++++--------
 4 files changed, 33 insertions(+), 8 deletions(-)

diff --git a/.gitignore b/.gitignore
index 76b3746..34f27b0 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,4 @@
 ebin/
 logs/
 test/*.beam
+/deps/proper/
diff --git a/Makefile b/Makefile
index 34c0fe9..3d80498 100644
--- a/Makefile
+++ b/Makefile
@@ -3,10 +3,14 @@
 	fresh-build \
 	compile \
 	clean \
+	deps \
+	deps-get \
+	deps-update \
 	dialyze \
 	test
 
 ci: \
+	deps \
 	compile \
 	test
 
@@ -20,6 +24,16 @@ compile:
 clean:
 	@rebar clean
 
+deps: \
+	deps-get \
+	deps-update
+
+deps-get:
+	@rebar get-deps
+
+deps-update:
+	@rebar update-deps
+
 dialyze:
 	@dialyzer ebin
 
diff --git a/rebar.config b/rebar.config
index a760517..986fa40 100644
--- a/rebar.config
+++ b/rebar.config
@@ -1 +1,6 @@
+%%% -*- mode: erlang -*-
 {clean_files, ["test/*.beam"]}.
+
+{deps,
+ [{proper, ".*", {git, "https://github.com/manopapad/proper.git", {tag, "v1.1"}}}]
+}.
diff --git a/test/hope_list_SUITE.erl b/test/hope_list_SUITE.erl
index 751157d..819c4fc 100644
--- a/test/hope_list_SUITE.erl
+++ b/test/hope_list_SUITE.erl
@@ -1,5 +1,7 @@
 -module(hope_list_SUITE).
 
+-include_lib("proper/include/proper.hrl").
+
 %% Callbacks
 -export(
     [ all/0
@@ -14,6 +16,8 @@
 
 -define(GROUP , hope_list).
 
+-define(PROPTEST(A), true = proper:quickcheck(A())).
+
 
 %% ============================================================================
 %% Common Test callbacks
@@ -35,11 +39,12 @@ groups() ->
 %% =============================================================================
 
 t_unique_preserve_order(_Cfg) ->
-    ListAGiven = [a, a, g, b, f, c, a, d, a, e, f, d],
-    ListBGiven = "australia",
-    ListAExpected = [a, g, b, f, c, d, e],
-    ListBExpected = "austrli",
-    ListAComputed = hope_list:unique_preserve_order(ListAGiven),
-    ListBComputed = hope_list:unique_preserve_order(ListBGiven),
-    ListAComputed = ListAExpected,
-    ListBComputed = ListBExpected.
+    ?PROPTEST(prop_unique_preserve_order).
+
+prop_unique_preserve_order() ->
+    ?FORALL(L, list(),
+            begin
+                Duplicates = L -- lists:usort(L),
+                hope_list:unique_preserve_order(L) ==
+                    lists:reverse(lists:reverse(L) -- Duplicates)
+            end).
-- 
2.20.1