Merge pull request #409 from sjrd/java-interface-ctor

Fix #407: Synthesize a constructor for Java interfaces.

tasty-query/shared/src/main/scala/tastyquery/reader/classfiles/ClassfileParser.scala

@@ -329,6 +329,18 @@ private[reader] object ClassfileParser {
       else if cls.isString then rctx.createStringMagicMethods(cls)
       else if cls.isJavaEnum then rctx.createEnumMagicMethods(cls)
 
+    // Synthesize a constructor for interfaces
+    if cls.isTrait then
+      val ctor = TermSymbol
+        .create(nme.Constructor, cls)
+        .withDeclaredType(cls.makePolyConstructorType(MethodType(Nil, Nil, rctx.UnitType)))
+        .withFlags(Method | JavaDefined, None)
+        .setAnnotations(Nil)
+        .autoFillParamSymss()
+      ctor.paramSymss.foreach(_.merge.foreach(_.setAnnotations(Nil)))
+      allRegisteredSymbols += ctor
+    end if
+
     loadMembers()
 
     val annotations = readAnnotations(cls, attributes)

test-sources/src/main/scala/simple_trees/ClassExtendsJavaInterface.scala

@@ -0,0 +1,3 @@
+package simple_trees
+
+class ClassExtendsJavaInterface extends javadefined.JavaInterface1()

test-sources/src/main/scala/simple_trees/ClassExtendsPolyJavaInterface.scala

@@ -0,0 +1,5 @@
+package simple_trees
+
+class ClassExtendsPolyJavaInterface extends java.util.function.Predicate[String]():
+  def test(t: String): Boolean = t.isEmpty()
+end ClassExtendsPolyJavaInterface