From 7b5c4f538cc1a1d1bf02b309f1e6286927901d87 Mon Sep 17 00:00:00 2001
From: Rico Tzschichholz <ricotz@ubuntu.com>
Date: Sun, 30 Jan 2022 18:07:23 +0100
Subject: [PATCH] vala: Improve check of generic type references in static
 contexts

Fixes https://gitlab.gnome.org/GNOME/vala/issues/1284
---
 tests/Makefile.am                             |  4 +++
 ...od-parameter-unknown-type-parameter-2.test |  9 +++++
 ...thod-parameter-unknown-type-parameter.test |  9 +++++
 ...ethod-return-unknown-type-parameter-2.test | 10 ++++++
 .../method-return-unknown-type-parameter.test | 10 ++++++
 vala/valamethod.vala                          | 34 +++++++++++++++++++
 6 files changed, 76 insertions(+)
 create mode 100644 tests/generics/method-parameter-unknown-type-parameter-2.test
 create mode 100644 tests/generics/method-parameter-unknown-type-parameter.test
 create mode 100644 tests/generics/method-return-unknown-type-parameter-2.test
 create mode 100644 tests/generics/method-return-unknown-type-parameter.test

diff --git a/tests/Makefile.am b/tests/Makefile.am
index cf9bd1e93..a502b3494 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -765,6 +765,10 @@ TESTS = \
 	generics/parameter-invalid-initializer.test \
 	generics/parameter-sizeof-initializer.vala \
 	generics/member-dup-destroy.vala \
+	generics/method-parameter-unknown-type-parameter.test \
+	generics/method-parameter-unknown-type-parameter-2.test \
+	generics/method-return-unknown-type-parameter.test \
+	generics/method-return-unknown-type-parameter-2.test \
 	generics/null-type.vala \
 	generics/property-gobject-set.vala \
 	generics/property-int-cast.vala \
diff --git a/tests/generics/method-parameter-unknown-type-parameter-2.test b/tests/generics/method-parameter-unknown-type-parameter-2.test
new file mode 100644
index 000000000..afbd77100
--- /dev/null
+++ b/tests/generics/method-parameter-unknown-type-parameter-2.test
@@ -0,0 +1,9 @@
+Invalid Code
+
+class Foo<G> {
+	static void bar (Foo<G> g) {
+	}
+}
+
+void main () {
+}
diff --git a/tests/generics/method-parameter-unknown-type-parameter.test b/tests/generics/method-parameter-unknown-type-parameter.test
new file mode 100644
index 000000000..f40ae8096
--- /dev/null
+++ b/tests/generics/method-parameter-unknown-type-parameter.test
@@ -0,0 +1,9 @@
+Invalid Code
+
+class Foo<G> {
+	static void bar (G g) {
+	}
+}
+
+void main () {
+}
diff --git a/tests/generics/method-return-unknown-type-parameter-2.test b/tests/generics/method-return-unknown-type-parameter-2.test
new file mode 100644
index 000000000..aef59eda8
--- /dev/null
+++ b/tests/generics/method-return-unknown-type-parameter-2.test
@@ -0,0 +1,10 @@
+Invalid Code
+
+class Foo<G> {
+	static Foo<G> bar () {
+		return null;
+	}
+}
+
+void main () {
+}
diff --git a/tests/generics/method-return-unknown-type-parameter.test b/tests/generics/method-return-unknown-type-parameter.test
new file mode 100644
index 000000000..f25d37183
--- /dev/null
+++ b/tests/generics/method-return-unknown-type-parameter.test
@@ -0,0 +1,10 @@
+Invalid Code
+
+class Foo<G> {
+	static G bar () {
+		return null;
+	}
+}
+
+void main () {
+}
diff --git a/vala/valamethod.vala b/vala/valamethod.vala
index fc8491594..2794cd48e 100644
--- a/vala/valamethod.vala
+++ b/vala/valamethod.vala
@@ -890,6 +890,19 @@ public class Vala.Method : Subroutine, Callable {
 			Report.error (source_reference, "[Print] methods must have exactly one parameter of type `string'");
 		}
 
+		// Collect generic type references
+		// TODO Can this be done in the SymbolResolver?
+		List<GenericType> referenced_generics = new ArrayList<GenericType> ();
+		var traverse = new TraverseVisitor (node => {
+			if (node is GenericType) {
+				referenced_generics.add ((GenericType) node);
+				return TraverseStatus.STOP;
+			}
+			return TraverseStatus.CONTINUE;
+		});
+
+		return_type.accept (traverse);
+
 		var optional_param = false;
 		var params_array_param = false;
 		var ellipsis_param = false;
@@ -907,6 +920,9 @@ public class Vala.Method : Subroutine, Callable {
 				Report.error (param.source_reference, "Variadic parameters are not supported for async methods");
 				return false;
 			}
+
+			param.accept_children (traverse);
+
 			// TODO: begin and end parameters must be checked separately for coroutines
 			if (coroutine) {
 				continue;
@@ -955,6 +971,24 @@ public class Vala.Method : Subroutine, Callable {
 			}
 		}
 
+		// Check if referenced type-parameters are present
+		// TODO Can this be done in the SymbolResolver?
+		if (binding == MemberBinding.STATIC && parent_symbol is Class && !((Class) parent_symbol).is_compact) {
+			Iterator<GenericType> ref_generics_it = referenced_generics.iterator ();
+			while (ref_generics_it.next ()) {
+				var ref_generics = ref_generics_it.get ();
+				foreach (var type_param in get_type_parameters ()) {
+					if (ref_generics.type_parameter.name == type_param.name) {
+						ref_generics_it.remove ();
+					}
+				}
+			}
+			foreach (var type in referenced_generics) {
+				error = true;
+				Report.error (type.source_reference, "The type name `%s' could not be found", type.type_parameter.name);
+			}
+		}
+
 		if (coroutine) {
 			// TODO: async methods with out-parameters before in-parameters are not supported
 			bool requires_pointer = false;
-- 
2.47.2