[vala/0.36] vala: Report invalid instance member access to property

[Rico Tzschichholz <ricotz src gnome org>]

commit 39af62623a81577b4e23da732ad7213b8053562d
Author: Rico Tzschichholz <ricotz ubuntu com>
Date:   Mon Dec 31 14:48:08 2018 +0100

    vala: Report invalid instance member access to property
    
    See https://gitlab.gnome.org/GNOME/vala/issues/605

 codegen/valaccodememberaccessmodule.vala |  8 +++++++
 tests/Makefile.am                        |  1 +
 tests/control-flow/bug790903-2.test      |  9 +++++++
 vala/Makefile.am                         |  1 +
 vala/valabinaryexpression.vala           |  4 ++--
 vala/valalocalvariable.vala              |  2 +-
 vala/valamemberaccess.vala               |  2 ++
 vala/valapropertyprototype.vala          | 41 ++++++++++++++++++++++++++++++++
 vala/valaunaryexpression.vala            |  2 +-
 9 files changed, 66 insertions(+), 4 deletions(-)
---
diff --git a/codegen/valaccodememberaccessmodule.vala b/codegen/valaccodememberaccessmodule.vala
index 49c1535f8..b8859b63f 100644
--- a/codegen/valaccodememberaccessmodule.vala
+++ b/codegen/valaccodememberaccessmodule.vala
@@ -166,6 +166,13 @@ public abstract class Vala.CCodeMemberAccessModule : CCodeControlFlowModule {
                                }
                        }
 
+                       if (pub_inst == null && prop.binding == MemberBinding.INSTANCE) {
+                               // FIXME Report this with proper source-reference on the vala side!
+                               Report.error (prop.source_reference, "Invalid access to instance member 
`%s'".printf (prop.get_full_name ()));
+                               set_cvalue (expr, new CCodeInvalidExpression ());
+                               return;
+                       }
+
                        if (expr.inner is BaseAccess) {
                                var base_prop = prop;
                                if (prop.base_property != null) {
@@ -304,6 +311,7 @@ public abstract class Vala.CCodeMemberAccessModule : CCodeControlFlowModule {
                                ccode.add_expression (ccall);
                                set_cvalue (expr, ctemp);
                        }
+
                        expr.target_value.value_type = expr.value_type;
                        expr.target_value = store_temp_value (expr.target_value, expr);
                } else if (expr.symbol_reference is LocalVariable) {
diff --git a/tests/Makefile.am b/tests/Makefile.am
index 0695ac7cb..19514bb69 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -147,6 +147,7 @@ TESTS = \
        control-flow/bug736774-1.vala \
        control-flow/bug736774-2.vala \
        control-flow/bug790903.test \
+       control-flow/bug790903-2.test \
        enums/enum_only.vala \
        enums/enums.vala \
        enums/flags.vala \
diff --git a/tests/control-flow/bug790903-2.test b/tests/control-flow/bug790903-2.test
new file mode 100644
index 000000000..5935f159a
--- /dev/null
+++ b/tests/control-flow/bug790903-2.test
@@ -0,0 +1,9 @@
+Invalid Code
+
+class Foo {
+       public string prop { get; set; }
+}
+
+void main () {
+       var foo = (string) Foo.prop;
+}
diff --git a/vala/Makefile.am b/vala/Makefile.am
index 397594cdc..8b85e4b7b 100644
--- a/vala/Makefile.am
+++ b/vala/Makefile.am
@@ -117,6 +117,7 @@ libvalacore_la_VALASOURCES = \
        valaprofile.vala \
        valapropertyaccessor.vala \
        valaproperty.vala \
+       valapropertyprototype.vala \
        valarealliteral.vala \
        valareferencetransferexpression.vala \
        valareferencetype.vala \
diff --git a/vala/valabinaryexpression.vala b/vala/valabinaryexpression.vala
index c32f629b4..3d574645f 100644
--- a/vala/valabinaryexpression.vala
+++ b/vala/valabinaryexpression.vala
@@ -300,12 +300,12 @@ public class Vala.BinaryExpression : Expression {
                        return false;
                }
 
-               if (left.value_type is FieldPrototype) {
+               if (left.value_type is FieldPrototype || left.value_type is PropertyPrototype) {
                        error = true;
                        Report.error (left.source_reference, "Access to instance member `%s' denied".printf 
(left.symbol_reference.get_full_name ()));
                        return false;
                }
-               if (right.value_type is FieldPrototype) {
+               if (right.value_type is FieldPrototype || right.value_type is PropertyPrototype) {
                        error = true;
                        Report.error (right.source_reference, "Access to instance member `%s' denied".printf 
(right.symbol_reference.get_full_name ()));
                        return false;
diff --git a/vala/valalocalvariable.vala b/vala/valalocalvariable.vala
index c11380700..337688f15 100644
--- a/vala/valalocalvariable.vala
+++ b/vala/valalocalvariable.vala
@@ -116,7 +116,7 @@ public class Vala.LocalVariable : Variable {
                                Report.error (source_reference, "var declaration not allowed with non-typed 
initializer");
                                return false;
                        }
-                       if (initializer.value_type is FieldPrototype) {
+                       if (initializer.value_type is FieldPrototype || initializer.value_type is 
PropertyPrototype) {
                                error = true;
                                Report.error (initializer.source_reference, "Access to instance member `%s' 
denied".printf (initializer.symbol_reference.get_full_name ()));
                                return false;
diff --git a/vala/valamemberaccess.vala b/vala/valamemberaccess.vala
index 09e7ea168..913fa05ae 100644
--- a/vala/valamemberaccess.vala
+++ b/vala/valamemberaccess.vala
@@ -771,6 +771,8 @@ public class Vala.MemberAccess : Expression {
                                value_type = context.analyzer.get_value_type_for_symbol (symbol_reference, 
lvalue);
                        } else if (symbol_reference is Field) {
                                value_type = new FieldPrototype ((Field) symbol_reference);
+                       } else if (symbol_reference is Property) {
+                               value_type = new PropertyPrototype ((Property) symbol_reference);
                        } else {
                                value_type = new InvalidType ();
                        }
diff --git a/vala/valapropertyprototype.vala b/vala/valapropertyprototype.vala
new file mode 100644
index 000000000..62306cd6c
--- /dev/null
+++ b/vala/valapropertyprototype.vala
@@ -0,0 +1,41 @@
+/* valafieldprototype.vala
+ *
+ * Copyright (C) 2018  Rico Tzschichholz
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301  USA
+ *
+ * Author:
+ *     Rico Tzschichholz <ricotz ubuntu com>
+ */
+
+/**
+ * A reference to an instance property without a specific instance.
+ */
+public class Vala.PropertyPrototype : DataType {
+       public weak Property property_symbol { get; set; }
+
+       public PropertyPrototype (Property property_symbol) {
+               this.property_symbol = property_symbol;
+       }
+
+       public override DataType copy () {
+               var result = new PropertyPrototype (property_symbol);
+               return result;
+       }
+
+       public override string to_qualified_string (Scope? scope) {
+               return property_symbol.get_full_name ();
+       }
+}
diff --git a/vala/valaunaryexpression.vala b/vala/valaunaryexpression.vala
index 95b0d4fc4..3adab0b2b 100644
--- a/vala/valaunaryexpression.vala
+++ b/vala/valaunaryexpression.vala
@@ -170,7 +170,7 @@ public class Vala.UnaryExpression : Expression {
                        return false;
                }
 
-               if (inner.value_type is FieldPrototype) {
+               if (inner.value_type is FieldPrototype || inner.value_type is PropertyPrototype) {
                        error = true;
                        Report.error (inner.source_reference, "Access to instance member `%s' denied".printf 
(inner.symbol_reference.get_full_name ()));
                        return false;