genbindings: support protected methods

cmd/genbindings/clang2il.go

@@ -185,6 +185,14 @@ func processTypedef(node map[string]interface{}, addNamePrefix string) (CppTyped
 	return CppTypedef{}, errors.New("processTypedef: ???")
 }
 
+type visibilityState int
+
+const (
+	VsPublic    visibilityState = 1
+	VsProtected                 = 2
+	VsPrivate                   = 3
+)
+
 // processClassType parses a single C++ class definition into our intermediate format.
 func processClassType(node map[string]interface{}, addNamePrefix string) (CppClass, error) {
 	var ret CppClass
@@ -229,10 +237,10 @@ func processClassType(node map[string]interface{}, addNamePrefix string) (CppCla
 		}
 	}
 
-	// Check if this was 'struct' (default visible) or 'class' (default invisible)
-	visibility := true
+	// Check if this was 'struct' (default public) or 'class' (default private)
+	visibility := VsPublic
 	if tagUsed, ok := node["tagUsed"].(string); ok && tagUsed == "class" {
-		visibility = false
+		visibility = VsPrivate
 	}
 
 	// Check if this is an abstract class
@@ -289,9 +297,11 @@ nextMethod:
 
 			switch access {
 			case "public":
-				visibility = true
-			case "private", "protected":
-				visibility = false
+				visibility = VsPublic
+			case "protected":
+				visibility = VsProtected
+			case "private":
+				visibility = VsPrivate
 			default:
 				panic("unexpected access visibility '" + access + "'")
 			}
@@ -315,7 +325,7 @@ nextMethod:
 			// Child class type definition e.g. QAbstractEventDispatcher::TimerInfo
 			// Parse as a whole child class
 
-			if !visibility {
+			if visibility != VsPublic {
 				continue // Skip private/protected
 			}
 
@@ -341,7 +351,7 @@ nextMethod:
 		case "EnumDecl":
 			// Child class enum
 
-			if !visibility {
+			if visibility != VsPublic {
 				continue // Skip private/protected
 			}
 
@@ -359,7 +369,7 @@ nextMethod:
 				// This is an implicit ctor. Therefore the class is constructable
 				// even if we're currently in a `private:` block.
 
-			} else if !visibility {
+			} else if visibility != VsPublic {
 				continue // Skip private/protected
 			}
 
@@ -403,7 +413,8 @@ nextMethod:
 				continue
 			}
 
-			if !visibility {
+			if visibility != VsPublic {
+				// TODO Is there any use case for allowing MIQT to overload a virtual destructor?
 				ret.CanDelete = false
 				continue
 			}
@@ -415,8 +426,12 @@ nextMethod:
 			}
 
 		case "CXXMethodDecl":
-			if !visibility {
-				continue // Skip private/protected
+
+			// If this is a virtual method, we want to allow overriding it even
+			// if it is protected
+			// But we can only call it if it is public
+			if visibility == VsPrivate {
+				continue // Skip private, ALLOW protected
 			}
 
 			// Check if this is `= delete`
@@ -648,6 +663,10 @@ func parseMethod(node map[string]interface{}, mm *CppMethod) error {
 		mm.IsStatic = true
 	}
 
+	if virtual, ok := node["virtual"].(bool); ok && virtual {
+		mm.IsVirtual = true
+	}
+
 	if methodInner, ok := node["inner"].([]interface{}); ok {
 		paramCounter := 0
 		for _, methodObj := range methodInner {