test: add test for title render

title.go

@@ -30,12 +30,21 @@ import (
 )
 
 type TitleOption struct {
-	Text         string
+	// Title text, support \n for new line
-	Subtext      string
+	Text string
-	Style        chart.Style
+	// Subtitle text, support \n for new line
+	Subtext string
+	// Title style
+	Style chart.Style
+	// Subtitle style
 	SubtextStyle chart.Style
-	Left         string
+	// Distance between title component and the left side of the container.
-	Top          string
+	// It can be pixel value: 20, percentage value: 20%,
+	// or position value: right, center.
+	Left string
+	// Distance between title component and the top side of the container.
+	// It can be pixel value: 20.
+	Top string
 }
 type titleMeasureOption struct {
 	width  int
@@ -138,7 +147,7 @@ func drawTitle(p *Draw, opt *TitleOption) (chart.Box, error) {
 	}
 	height := titleY + padding.Top + padding.Bottom
 	box := padding.Clone()
-	box.Right = box.Left + width
+	box.Right = box.Left + titleX + width
 	box.Bottom = box.Top + height
 
 	return box, nil

title_test.go

@@ -0,0 +1,128 @@
+// MIT License
+
+// Copyright (c) 2022 Tree Xie
+
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+
+package charts
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/wcharczuk/go-chart/v2"
+	"github.com/wcharczuk/go-chart/v2/drawing"
+)
+
+func TestSplitTitleText(t *testing.T) {
+	assert := assert.New(t)
+
+	assert.Equal([]string{
+		"a",
+		"b",
+	}, splitTitleText("a\nb"))
+	assert.Equal([]string{
+		"a",
+	}, splitTitleText("a\n "))
+}
+
+func TestDrawTitle(t *testing.T) {
+	assert := assert.New(t)
+
+	newOption := func() *TitleOption {
+		f, _ := chart.GetDefaultFont()
+		return &TitleOption{
+			Text:    "title\nHello",
+			Subtext: "subtitle\nWorld!",
+			Style: chart.Style{
+				FontSize:  14,
+				Font:      f,
+				FontColor: drawing.ColorBlack,
+			},
+			SubtextStyle: chart.Style{
+				FontSize:  10,
+				Font:      f,
+				FontColor: drawing.ColorBlue,
+			},
+		}
+	}
+	newDraw := func() *Draw {
+		d, _ := NewDraw(DrawOption{
+			Width:  400,
+			Height: 300,
+		})
+		return d
+	}
+
+	tests := []struct {
+		newDraw   func() *Draw
+		newOption func() *TitleOption
+		result    string
+		box       chart.Box
+	}{
+		{
+			newDraw:   newDraw,
+			newOption: newOption,
+			result:    "<svg xmlns=\"http://www.w3.org/2000/svg\" xmlns:xlink=\"http://www.w3.org/1999/xlink\" width=\"400\" height=\"300\">\\n<text x=\"6\" y=\"0\" style=\"stroke-width:0;stroke:none;fill:rgba(0,0,0,1.0);font-size:17.9px;font-family:'Roboto Medium',sans-serif\">title</text><text x=\"0\" y=\"17\" style=\"stroke-width:0;stroke:none;fill:rgba(0,0,0,1.0);font-size:17.9px;font-family:'Roboto Medium',sans-serif\">Hello</text><text x=\"0\" y=\"34\" style=\"stroke-width:0;stroke:none;fill:rgba(0,0,255,1.0);font-size:12.8px;font-family:'Roboto Medium',sans-serif\">subtitle</text><text x=\"3\" y=\"46\" style=\"stroke-width:0;stroke:none;fill:rgba(0,0,255,1.0);font-size:12.8px;font-family:'Roboto Medium',sans-serif\">World!</text></svg>",
+			box: chart.Box{
+				Right:  43,
+				Bottom: 58,
+			},
+		},
+		{
+			newDraw: newDraw,
+			newOption: func() *TitleOption {
+				opt := newOption()
+				opt.Left = PositionRight
+				opt.Top = "50"
+				return opt
+			},
+			result: "<svg xmlns=\"http://www.w3.org/2000/svg\" xmlns:xlink=\"http://www.w3.org/1999/xlink\" width=\"400\" height=\"300\">\\n<text x=\"363\" y=\"50\" style=\"stroke-width:0;stroke:none;fill:rgba(0,0,0,1.0);font-size:17.9px;font-family:'Roboto Medium',sans-serif\">title</text><text x=\"357\" y=\"67\" style=\"stroke-width:0;stroke:none;fill:rgba(0,0,0,1.0);font-size:17.9px;font-family:'Roboto Medium',sans-serif\">Hello</text><text x=\"357\" y=\"84\" style=\"stroke-width:0;stroke:none;fill:rgba(0,0,255,1.0);font-size:12.8px;font-family:'Roboto Medium',sans-serif\">subtitle</text><text x=\"360\" y=\"96\" style=\"stroke-width:0;stroke:none;fill:rgba(0,0,255,1.0);font-size:12.8px;font-family:'Roboto Medium',sans-serif\">World!</text></svg>",
+			box: chart.Box{
+				Right:  400,
+				Bottom: 108,
+			},
+		},
+		{
+			newDraw: newDraw,
+			newOption: func() *TitleOption {
+				opt := newOption()
+				opt.Left = PositionCenter
+				opt.Top = "10"
+				return opt
+			},
+			result: "<svg xmlns=\"http://www.w3.org/2000/svg\" xmlns:xlink=\"http://www.w3.org/1999/xlink\" width=\"400\" height=\"300\">\\n<text x=\"185\" y=\"10\" style=\"stroke-width:0;stroke:none;fill:rgba(0,0,0,1.0);font-size:17.9px;font-family:'Roboto Medium',sans-serif\">title</text><text x=\"179\" y=\"27\" style=\"stroke-width:0;stroke:none;fill:rgba(0,0,0,1.0);font-size:17.9px;font-family:'Roboto Medium',sans-serif\">Hello</text><text x=\"179\" y=\"44\" style=\"stroke-width:0;stroke:none;fill:rgba(0,0,255,1.0);font-size:12.8px;font-family:'Roboto Medium',sans-serif\">subtitle</text><text x=\"182\" y=\"56\" style=\"stroke-width:0;stroke:none;fill:rgba(0,0,255,1.0);font-size:12.8px;font-family:'Roboto Medium',sans-serif\">World!</text></svg>",
+			box: chart.Box{
+				Right:  222,
+				Bottom: 68,
+			},
+		},
+	}
+	for _, tt := range tests {
+		d := tt.newDraw()
+		o := tt.newOption()
+		b, err := drawTitle(d, o)
+		assert.Nil(err)
+		assert.Equal(tt.box, b)
+		data, err := d.Bytes()
+		assert.Nil(err)
+		assert.NotEmpty(data)
+		assert.Equal(tt.result, string(data))
+	}
+}