fix engines priorities so that html->pdf is done by wpd by default (ie, always)

HISTORY.rst

 Release history
 ===============
 
+0.3.3
+-----
+
+- fix engines priorities so that html->pdf is done by wpd by default (ie, always)
+
 0.3.2 (2020-04-22)
 ------------------
 

engines/wpd/engine.go

@@ -32,7 +32,7 @@
 		Type:        "Weasyprint",
 		Description: `Render HTML to PDF with weasyprint.`,
 		Transitions: []rendering.EngineTransitionInfo{
-			{FromType: "text/html", ToType: "application/pdf", Priority: 1.0},
+			{FromType: "text/html", ToType: "application/pdf", Priority: 2.0},
 		},
 		Metadata: []rendering.EngineMetadataInfo{
 			{

rendering/registry.go

@@ -4,6 +4,7 @@
 	"context"
 	"errors"
 	"fmt"
+	"sort"
 )
 
 // ErrDuplicateName is returned by EngineRegistry.Register if and engine with
@@ -189,6 +190,9 @@
 			}
 		}
 	}
+	sort.Slice(entries, func(i, j int) bool {
+		return entries[i].priority > entries[j].priority
+	})
 	var engines = make([]Engine, 0, len(entries))
 	for _, entry := range entries {
 		engines = append(engines, entry.engine)