国际象棋 (#720)

* init commit for chess

* fix lint & error

* remove issue link

* fix lint

* remove embed

* regex fix

* use strings.Builder

* 改不动了，先 push 了备份下

* 基本上改好了

* limit

* 使用等宽字体渲染棋盘

* use syncx

* 不会更新依赖库😭

* 先 push 备份下

* 更新依赖版本，确保能读取到字体文件

* fix log

plugin/chess/elo_test.go

@@ -0,0 +1,80 @@
+package chess
+
+import (
+	"math"
+	"testing"
+)
+
+func TestCalculateNewRate(t *testing.T) {
+	type args struct {
+		whiteRate  int
+		blackRate  int
+		whiteScore float64
+		blackScore float64
+	}
+	tests := []struct {
+		name  string
+		args  args
+		want  int
+		want1 int
+	}{
+		{
+			name: "test1",
+			args: args{
+				whiteRate:  1613,
+				blackRate:  1573,
+				whiteScore: 0.5,
+				blackScore: 0.5,
+			},
+			want:  1611,
+			want1: 1575,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got, got1 := calculateNewRate(tt.args.whiteRate, tt.args.blackRate, tt.args.whiteScore, tt.args.blackScore)
+			if got != tt.want {
+				t.Errorf("CalculateNewRate() got = %v, want %v", got, tt.want)
+			}
+			if got1 != tt.want1 {
+				t.Errorf("CalculateNewRate() got1 = %v, want %v", got1, tt.want1)
+			}
+		})
+	}
+}
+
+func Test_calculateException(t *testing.T) {
+	type args struct {
+		rate         int
+		opponentRate int
+	}
+	tests := []struct {
+		name string
+		args args
+		want float64
+	}{
+		{
+			name: "test1",
+			args: args{
+				rate:         1613,
+				opponentRate: 1573,
+			},
+			want: 0.5573116,
+		},
+		{
+			name: "test2",
+			args: args{
+				rate:         1613,
+				opponentRate: 1613,
+			},
+			want: 0.5,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if got := calculateException(tt.args.rate, tt.args.opponentRate); math.Abs(got-tt.want) > 0.0001 {
+				t.Errorf("calculateException() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}