From b2709eeb419eef22a889b07eaafd2867b37e28a6 Mon Sep 17 00:00:00 2001
From: Alexander Iljin <ajsoft@yandex.ru>
Date: Sun, 25 Dec 2016 02:24:13 +0300
Subject: [PATCH] google.charts: fix tests, add comments

---
 extra/google/charts/charts-tests.factor | 42 ++++++++++++++-----------
 1 file changed, 24 insertions(+), 18 deletions(-)

diff --git a/extra/google/charts/charts-tests.factor b/extra/google/charts/charts-tests.factor
index 6dd9c7640f..efa9694bca 100644
--- a/extra/google/charts/charts-tests.factor
+++ b/extra/google/charts/charts-tests.factor
@@ -4,23 +4,17 @@ USING: accessors colors.constants google.charts
 google.charts.private kernel math present sequences tools.test ;
 IN: google.charts.tests
 
-{ t } [
-
-    { 0 0 } <line>
-    { 0 0 } <line> COLOR: red >>background
-    [ chart>url present length ] bi@ <
-] unit-test
+! The order of the constructors below is important, because we
+! are testing side-effects. If you remove the clone word from
+! chart>url implementation, the second object in each test
+! will incorrectly result in the same URL as the first one
+! (although the order of parameters in the URL may vary).
+! The order of tests is important for the same reason.
 
 { t } [
-    { 0 0 } <line>
-    { 0 0 } <line> COLOR: red >>foreground
-    [ chart>url present length ] bi@ <
-] unit-test
-
-{ t } [
-    "" <formula>
     "" <formula> t >>data-scale
-    [ chart>url present length ] bi@ <
+    "" <formula>
+    [ chart>url present length ] bi@ >
 ] unit-test
 
 { t } [
@@ -30,13 +24,25 @@ IN: google.charts.tests
 ] unit-test
 
 { t } [
+    { 0 0 } <line> COLOR: red >>background
     { 0 0 } <line>
-    { 0 0 } <line> { 0 0 } >>margin
-    [ chart>url present length ] bi@ <
+    [ chart>url present length ] bi@ >
 ] unit-test
 
 { t } [
+    { 0 0 } <line> COLOR: red >>foreground
     { 0 0 } <line>
-    { 0 0 } <line> 5 >>bar-width
-    [ chart>url present length ] bi@ <
+    [ chart>url present length ] bi@ >
+] unit-test
+
+{ t } [
+    { 0 0 } <line> { 0 0 } >>margin
+    { 0 0 } <line>
+    [ chart>url present length ] bi@ >
+] unit-test
+
+{ t } [
+    { 0 0 } <line> 5 >>bar-width
+    { 0 0 } <line>
+    [ chart>url present length ] bi@ >
 ] unit-test