internal/rosa/meson: always prepend D

All flags in practice use this convention. An escape hatch is available by leaving the value empty.

Signed-off-by: Ophestra <cat@gensokyo.uk>

internal/rosa/meson.go

@@ -56,8 +56,8 @@ func (*MesonHelper) wantsDir() (string, bool) { return `"$(mktemp -d)"`, false }
 
 // isPython returns whether the legacy python implementation is used.
 func (attr *MesonHelper) isPython() bool {
-	return attr != nil &&
-		(!attr.Muon || len(attr.SkipTests) != 0 || attr.InteractiveTest)
+	return attr == nil ||
+		!attr.Muon || len(attr.SkipTests) != 0 || attr.InteractiveTest
 }
 
 // script generates the cure script.
@@ -106,16 +106,13 @@ func (attr *MesonHelper) script(t Toolchain, name string) string {
 ` + muon + ` setup \
 	` + strings.Join(slices.Collect(func(yield func(string) bool) {
 		for _, v := range append([]KV{
-			{"Dwrap_mode", "nofallback"},
-			{"Dprefix", "/system"},
-			{"Dbuildtype", "release"},
+			{"wrap_mode", "nofallback"},
+			{"prefix", "/system"},
+			{"buildtype", "release"},
 		}, attr.Setup...) {
-			s := "-" + v[0]
-			if len(v[0]) > 0 && v[0][0] != 'D' {
-				s = "-" + s
-			}
+			s := v[0]
 			if v[1] != "" {
-				s += "=" + v[1]
+				s = "-D" + s + "=" + v[1]
 			}
 			if !yield(s) {
 				return