From: Rico Tzschichholz <ricotz@ubuntu.com>
Date: Sat, 4 Jul 2020 07:07:06 +0000 (+0200)
Subject: vala: Property must be writable when invoking ReturnsModifiedPointer method
X-Git-Tag: 0.46.12~33
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f3f9cae9e19b20a9f8813d290f707fc9935e0c97;p=thirdparty%2Fvala.git

vala: Property must be writable when invoking ReturnsModifiedPointer method

Fixes https://gitlab.gnome.org/GNOME/vala/issues/1023
---

diff --git a/tests/Makefile.am b/tests/Makefile.am
index ce55ed22b..87830dd49 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -868,6 +868,7 @@ TESTS = \
 	semantic/property-accessibility.test \
 	semantic/property-construct.test \
 	semantic/property-initializer-type.test \
+	semantic/property-method-returns-modified-pointer.test \
 	semantic/property-override.test \
 	semantic/property-override-class.test \
 	semantic/property-override-interface.test \
diff --git a/tests/semantic/property-method-returns-modified-pointer.test b/tests/semantic/property-method-returns-modified-pointer.test
new file mode 100644
index 000000000..ae8ebbe6f
--- /dev/null
+++ b/tests/semantic/property-method-returns-modified-pointer.test
@@ -0,0 +1,10 @@
+Invalid Code
+
+class Foo {
+	public List<string> bar { get; }
+}
+
+void main () {
+	var foo = new Foo ();
+	foo.bar.append ("foo");
+}
diff --git a/vala/valamethodcall.vala b/vala/valamethodcall.vala
index a1782217a..980bd3f86 100644
--- a/vala/valamethodcall.vala
+++ b/vala/valamethodcall.vala
@@ -532,7 +532,13 @@ public class Vala.MethodCall : Expression {
 				value_type.floating_reference = true;
 			}
 			if (m.returns_modified_pointer) {
-				((MemberAccess) call).inner.lvalue = true;
+				unowned Expression inner = ((MemberAccess) call).inner;
+				inner.lvalue = true;
+				unowned Property? prop = inner.symbol_reference as Property;
+				if (prop != null && (prop.set_accessor == null || !prop.set_accessor.writable)) {
+					error = true;
+					Report.error (inner.source_reference, "Property `%s' is read-only".printf (prop.get_full_name ()));
+				}
 			}
 			// avoid passing possible null to ref_sink_function without checking
 			if (tree_can_fail && !value_type.nullable && value_type.floating_reference && ret_type is ObjectType) {