From d95d87c0d8e44d2b030e1528c396c62846e5f7ff Mon Sep 17 00:00:00 2001
From: Karma Riuk <riukkarma@gmail.com>
Date: Mon, 14 Aug 2023 15:08:27 +0200
Subject: [PATCH] Finally written some good tests for the image writer

---
 io/writer/image_test.go | 177 ++++++++++++++++++++++++++--------------
 1 file changed, 114 insertions(+), 63 deletions(-)

diff --git a/io/writer/image_test.go b/io/writer/image_test.go
index 9479918..fc923ae 100644
--- a/io/writer/image_test.go
+++ b/io/writer/image_test.go
@@ -1,71 +1,122 @@
 package writer
 
 import (
+	"bytes"
+	"image/color"
+	"io"
+	"maze-solver/maze"
+	"os"
 	"testing"
+
+	"github.com/mazznoer/colorgrad"
+)
+
+const (
+	OUT_DIR      = "./out"
+	EXPECTED_DIR = "../../assets/solved"
 )
 
 func TestImageWriter(t *testing.T) {
-	// pathGradient, err := colorgrad.NewGradient().Colors(color.White).Build()
-	// if err != nil {
-	// 	panic(err)
-	// }
-	//
-	// tests := []struct {
-	// 	name                  string
-	// 	filename              string
-	// 	m                     *maze.SolvedMaze
-	// 	CellWidth, cellHeight int
-	// 	pathColor, wallColor  color.Color
-	// 	gradient              colorgrad.Gradient
-	// }{
-	// 	{
-	// 		"Trivial",
-	// 		"../../out/trivial_sol.png",
-	// 		trivial(),
-	// 		40, 40,
-	// 		color.White, color.Black,
-	// 		colorgrad.Warm(),
-	// 	},
-	// 	{
-	// 		"Bigger",
-	// 		"../../out/bigger_sol.png",
-	// 		bigger(),
-	// 		40, 40,
-	// 		color.White, color.Black,
-	// 		colorgrad.Warm(),
-	// 	},
-	// 	{
-	// 		"Bigger Staggered",
-	// 		"../../out/bigger_staggered_sol.png",
-	// 		bigger_staggered(),
-	// 		40, 40,
-	// 		color.White, color.Black,
-	// 		pathGradient,
-	// 	},
-	// 	{
-	// 		"Normal",
-	// 		"../../out/normal_sol.png",
-	// 		normal(),
-	// 		40, 40,
-	// 		color.White, color.Black,
-	// 		colorgrad.Warm(),
-	// 	},
-	// }
-	//
-	// for _, test := range tests {
-	// 	writer := ImageWriter{
-	// 		Filename:         test.filename,
-	// 		Maze:             test.m,
-	// 		CellWidth:        test.CellWidth,
-	// 		CellHeight:       test.cellHeight,
-	// 		WallColor:        test.wallColor,
-	// 		PathColor:        test.pathColor,
-	// 		SolutionGradient: test.gradient,
-	// 	}
-	//
-	// 	err := writer.Write()
-	// 	if err != nil {
-	// 		t.Fatalf("%s: couldn't write solution, got following error\n%v", test.name, err)
-	// 	}
-	// }
+	if _, err := os.Stat(OUT_DIR); os.IsNotExist(err) {
+		os.Mkdir(OUT_DIR, 0700)
+	}
+
+	tests := []struct {
+		name                  string
+		filename              string
+		m                     *maze.SolvedMaze
+		CellWidth, cellHeight int
+		pathColor, wallColor  color.Color
+		gradient              colorgrad.Gradient
+	}{
+		{
+			"Trivial",
+			"trivial.png",
+			trivial(),
+			20, 20,
+			color.White, color.Black,
+			colorgrad.Warm(),
+		},
+		{
+			"Trivial Bigger",
+			"trivial-bigger.png",
+			bigger(),
+			20, 20,
+			color.White, color.Black,
+			colorgrad.Warm(),
+		},
+		{
+			"Trivial Bigger Staggered",
+			"trivial-bigger-staggered.png",
+			bigger_staggered(),
+			20, 20,
+			color.White, color.Black,
+			colorgrad.Warm(),
+		},
+		{
+			"Normal",
+			"normal.png",
+			normal(),
+			20, 20,
+			color.White, color.Black,
+			colorgrad.Warm(),
+		},
+	}
+
+	for _, test := range tests {
+		writer := ImageWriter{
+			Filename:         OUT_DIR + "/" + test.filename,
+			Maze:             test.m,
+			CellWidth:        test.CellWidth,
+			CellHeight:       test.cellHeight,
+			WallColor:        test.wallColor,
+			PathColor:        test.pathColor,
+			SolutionGradient: test.gradient,
+		}
+
+		err := writer.Write()
+		if err != nil {
+			t.Fatalf("%s: couldn't write solution, got following error\n%v", test.name, err)
+		}
+
+		assertEqualFile(t, EXPECTED_DIR+"/"+test.filename, OUT_DIR+"/"+test.filename, test.name)
+		os.Remove(writer.Filename)
+	}
+	os.Remove(OUT_DIR)
+}
+
+const chunkSize = 64000
+
+func assertEqualFile(t *testing.T, file1, file2, name string) {
+	f1, err := os.Open(file1)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer f1.Close()
+
+	f2, err := os.Open(file2)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer f2.Close()
+
+	for {
+		b1 := make([]byte, chunkSize)
+		_, err1 := f1.Read(b1)
+
+		b2 := make([]byte, chunkSize)
+		_, err2 := f2.Read(b2)
+
+		if err1 != nil || err2 != nil {
+			if err1 == io.EOF && err2 == io.EOF {
+				return
+			} else if err1 == io.EOF || err2 == io.EOF {
+				t.Fatalf("%s: files are not equal. Got %q, wanted %q", name, file1, file2)
+			}
+		}
+
+		if !bytes.Equal(b1, b2) {
+			t.Fatalf("%s: files are not equal. Got %q, wanted %q", name, file1, file2)
+		}
+	}
 }