go-chart/chart_test.go

package chart

import (
	"bytes"
	"testing"
	"time"

	"github.com/blendlabs/go-assert"
)

func TestChartGetDPI(t *testing.T) {
	assert := assert.New(t)

	unset := Chart{}
	assert.Equal(DefaultDPI, unset.GetDPI())
	assert.Equal(192, unset.GetDPI(192))

	set := Chart{DPI: 128}
	assert.Equal(128, set.GetDPI())
	assert.Equal(128, set.GetDPI(192))
}

func TestChartGetFont(t *testing.T) {
	assert := assert.New(t)

	f, err := GetDefaultFont()
	assert.Nil(err)

	unset := Chart{}
	assert.Nil(unset.GetFont())

	set := Chart{Font: f}
	assert.NotNil(set.GetFont())
}

func TestChartGetWidth(t *testing.T) {
	assert := assert.New(t)

	unset := Chart{}
	assert.Equal(DefaultChartWidth, unset.GetWidth())

	set := Chart{Width: DefaultChartWidth + 10}
	assert.Equal(DefaultChartWidth+10, set.GetWidth())
}

func TestChartGetHeight(t *testing.T) {
	assert := assert.New(t)

	unset := Chart{}
	assert.Equal(DefaultChartHeight, unset.GetHeight())

	set := Chart{Height: DefaultChartHeight + 10}
	assert.Equal(DefaultChartHeight+10, set.GetHeight())
}

func TestChartGetRanges(t *testing.T) {
	assert := assert.New(t)

	c := Chart{
		Series: []Series{
			ContinuousSeries{
				XValues: []float64{-2.0, -1.0, 0, 1.0, 2.0},
				YValues: []float64{1.0, 2.0, 3.0, 4.0, 4.5},
			},
			ContinuousSeries{
				XValues: []float64{1.0, 2.0, 3.0, 4.0, 5.0},
				YValues: []float64{-2.1, -1.0, 0, 1.0, 2.0},
			},
			ContinuousSeries{
				YAxis:   YAxisSecondary,
				XValues: []float64{1.0, 2.0, 3.0, 4.0, 5.0},
				YValues: []float64{10.0, 11.0, 12.0, 13.0, 14.0},
			},
		},
	}

	xrange, yrange, yrangeAlt := c.getRanges()
	assert.Equal(-2.0, xrange.Min)
	assert.Equal(5.0, xrange.Max)

	assert.Equal(-2.1, yrange.Min)
	assert.Equal(4.5, yrange.Max)

	assert.Equal(10.0, yrangeAlt.Min)
	assert.Equal(14.0, yrangeAlt.Max)

	cSet := Chart{
		XAxis: XAxis{
			Range: Range{Min: 9.8, Max: 19.8},
		},
		YAxis: YAxis{
			Range: Range{Min: 9.9, Max: 19.9},
		},
		YAxisSecondary: YAxis{
			Range: Range{Min: 9.7, Max: 19.7},
		},
		Series: []Series{
			ContinuousSeries{
				XValues: []float64{-2.0, -1.0, 0, 1.0, 2.0},
				YValues: []float64{1.0, 2.0, 3.0, 4.0, 4.5},
			},
			ContinuousSeries{
				XValues: []float64{1.0, 2.0, 3.0, 4.0, 5.0},
				YValues: []float64{-2.1, -1.0, 0, 1.0, 2.0},
			},
			ContinuousSeries{
				YAxis:   YAxisSecondary,
				XValues: []float64{1.0, 2.0, 3.0, 4.0, 5.0},
				YValues: []float64{10.0, 11.0, 12.0, 13.0, 14.0},
			},
		},
	}

	xr2, yr2, yra2 := cSet.getRanges()
	assert.Equal(9.8, xr2.Min)
	assert.Equal(19.8, xr2.Max)

	assert.Equal(9.9, yr2.Min)
	assert.Equal(19.9, yr2.Max)

	assert.Equal(9.7, yra2.Min)
	assert.Equal(19.7, yra2.Max)
}

// TestChartSingleSeries is more of a sanity check than anything.
func TestChartSingleSeries(t *testing.T) {
	assert := assert.New(t)
	now := time.Now()
	c := Chart{
		Title:  "Hello!",
		Width:  1024,
		Height: 400,
		YAxis: YAxis{
			Range: Range{
				Min: 0.0,
				Max: 4.0,
			},
		},
		Series: []Series{
			TimeSeries{
				Name:    "goog",
				XValues: []time.Time{now.AddDate(0, 0, -3), now.AddDate(0, 0, -2), now.AddDate(0, 0, -1)},
				YValues: []float64{1.0, 2.0, 3.0},
			},
		},
	}

	buffer := bytes.NewBuffer([]byte{})
	c.Render(PNG, buffer)
	assert.NotEmpty(buffer.Bytes())
}