generated code: always return typed value if present

Previously, RequestWith would ignore any return if an error was
encountered.

Now, RequestWith returns any value present even if there is an error --
basically a typed pass through.

We also pipe the output through gofumpt twice now to ensure we get
desired output:

   ref: mvdan/gofumpt#132

generate/gen.go

@@ -697,12 +697,12 @@ func (s Struct) WriteDecodeFunc(l *LineWriter) {
 
 func (s Struct) WriteRequestWithFunc(l *LineWriter) {
 	l.Write("// RequestWith is requests v on r and returns the response or an error.")
+	l.Write("// For sharded requests, the response may be merged and still return an error.")
+	l.Write("// It is better to rely on client.RequestSharded than to rely on proper merging behavior.")
 	l.Write("func (v *%s) RequestWith(ctx context.Context, r Requestor) (*%s, error) {", s.Name, s.ResponseKind)
 	l.Write("kresp, err := r.Request(ctx, v)")
-	l.Write("if err != nil {")
-	l.Write("return nil, err")
-	l.Write("}")
-	l.Write("return kresp.(*%s), nil", s.ResponseKind)
+	l.Write("resp, _ := kresp.(*%s)", s.ResponseKind)
+	l.Write("return resp, err")
 	l.Write("}")
 }
 

generate/main.go

@@ -372,7 +372,7 @@ func (l *LineWriter) Write(line string, args ...interface{}) {
 	l.line++
 }
 
-//go:generate sh -c "go run . | gofumpt > ../pkg/kmsg/generated.go"
+//go:generate sh -c "go run . | gofumpt | gofumpt > ../pkg/kmsg/generated.go"
 func main() {
 	const dir = "definitions"
 	const enums = "enums"