From 6eb3dac397506a3f0e2710c408635118557cf62e Mon Sep 17 00:00:00 2001
From: Timo Hocker <thocker@oas.de>
Date: Tue, 28 Apr 2020 10:58:37 +0200
Subject: [PATCH] fix

---
 lib/Graph.ts  | 10 +++++-----
 test/Graph.ts | 25 ++++++++++++++++++++++++-
 2 files changed, 29 insertions(+), 6 deletions(-)

diff --git a/lib/Graph.ts b/lib/Graph.ts
index a61693a..4d2c53d 100644
--- a/lib/Graph.ts
+++ b/lib/Graph.ts
@@ -27,15 +27,15 @@ export class Graph extends Element {
   private get attributes (): Array<{name: string; value: string}> {
     const attributes = [];
 
-    if (this.color)
+    if (typeof this.color !== 'undefined')
       attributes.push ({ name: 'color', value: this.color.toString () });
-    if (this.style)
+    if (typeof this.style !== 'undefined')
       attributes.push ({ name: 'style', value: this.style.toString () });
-    if (this.overlap)
+    if (typeof this.overlap !== 'undefined')
       attributes.push ({ name: 'overlap', value: this.overlap.toString () });
-    if (this.splines)
+    if (typeof this.splines !== 'undefined')
       attributes.push ({ name: 'splines', value: this.splines.toString () });
-    if (this.layout)
+    if (typeof this.layout !== 'undefined')
       attributes.push ({ name: 'layout', value: this.layout.toString () });
 
     return attributes;
diff --git a/test/Graph.ts b/test/Graph.ts
index 2826a56..4208017 100644
--- a/test/Graph.ts
+++ b/test/Graph.ts
@@ -1,5 +1,5 @@
 import test from 'ava';
-import { Graph, GraphStyles, Color, NodeStyles } from '../lib';
+import { Graph, GraphStyles, Color, NodeStyles, GraphLayouts } from '../lib';
 
 const result = `digraph foo {
   subgraph cluster_foo_baz {
@@ -39,6 +39,14 @@ const non_directional = `graph foo {
   foo_bar_baz -- foo_foo
 }`;
 
+const attributes = `digraph attr {
+  color = #000000
+  style = bold
+  overlap = false
+  splines = true
+  layout = neato
+}`;
+
 test ('serialize', (t) => {
   const g = new Graph ('foo');
 
@@ -70,6 +78,7 @@ test ('serialize', (t) => {
 
   const baz = g.add_node ('baz');
   const foo = g.add_node ('foo');
+
   g.add_edge (foo, baz);
 
   const serialized = g.toString ();
@@ -79,6 +88,7 @@ test ('serialize', (t) => {
 
 test ('non directional', (t) => {
   const g = new Graph ('foo');
+
   g.directional = false;
 
   let n = '';
@@ -92,7 +102,20 @@ test ('non directional', (t) => {
   });
 
   const f = g.add_node ('foo');
+
   g.add_edge (n, f);
 
   t.is (g.toString (), non_directional);
 });
+
+test ('attributes', (t) => {
+  const g = new Graph ('attr');
+
+  g.layout = GraphLayouts.neato;
+  g.overlap = false;
+  g.splines = true;
+  g.color = Color.black;
+  g.style = GraphStyles.bold;
+
+  t.is (g.toString (), attributes);
+});