add-cmpimg-approx

Signed-off-by: Sebastien Binet <binet@cern.ch>

Author: sbinet

vg/vg_test.go

@@ -19,6 +19,10 @@ import (
 	"gonum.org/v1/plot/vg"
 )
 
+const (
+	cmpDelta = 0.1
+)
+
 // TestLineWidth tests output against test images generated by
 // running tests with -tag good.
 func TestLineWidth(t *testing.T) {
@@ -68,7 +72,7 @@ func TestLineWidth(t *testing.T) {
 				t.Fatalf("failed to read test image [%s]: %v\n", name, err)
 			}
 
-			ok, err := cmpimg.EqualApprox(typ, buf.Bytes(), want, 0.1)
+			ok, err := cmpimg.EqualApprox(typ, buf.Bytes(), want, cmpDelta)
 			if err != nil {
 				t.Fatalf("failed to run cmpimg test [%s]: %v\n", name, err)
 			}

vg/vgimg/vgimg_test.go

@@ -154,7 +154,7 @@ func TestIssue687(t *testing.T) {
 		fname = "testdata/issue687.png"
 		size  = 500
 	)
-	cmpimg.CheckPlot(func() {
+	cmpimg.CheckPlotApprox(func() {
 		p := plot.New()
 		p.Title.Text = "Issue 687"
 		p.X.Label.Text = "X"
@@ -175,5 +175,5 @@ func TestIssue687(t *testing.T) {
 			t.Fatal(err)
 		}
 
-	}, t, filepath.Base(fname))
+	}, t, filepath.Base(fname), 0.1)
 }