[vala/0.40] parser: Improve error message for invalid ArrayCreationExpression

[Rico Tzschichholz <ricotz src gnome org>]

commit fba985ea2943f96d3f6ad9f3f74e1bf48c1e9ed7
Author: Rico Tzschichholz <ricotz ubuntu com>
Date:   Thu Mar 19 09:53:27 2020 +0100

    parser: Improve error message for invalid ArrayCreationExpression
    
    Fixes https://gitlab.gnome.org/GNOME/vala/issues/939

 tests/Makefile.am                        | 1 +
 tests/parser/array-creation-invalid.test | 5 +++++
 vala/valaparser.vala                     | 3 +++
 3 files changed, 9 insertions(+)
---
diff --git a/tests/Makefile.am b/tests/Makefile.am
index 9a1fca9b3..91ed789e1 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -529,6 +529,7 @@ TESTS = \
        scanner/string-escape-u-digit-length.test \
        scanner/string-escape-x-digit-length.test \
        scanner/string-escape-x.vala \
+       parser/array-creation-invalid.test \
        parser/assignment.vala \
        parser/attribute-duplicate.test \
        parser/attribute-wrong-number.test \
diff --git a/tests/parser/array-creation-invalid.test b/tests/parser/array-creation-invalid.test
new file mode 100644
index 000000000..22d439d3d
--- /dev/null
+++ b/tests/parser/array-creation-invalid.test
@@ -0,0 +1,5 @@
+Invalid Code
+
+void main () {
+       var foo = new int[];
+}
diff --git a/vala/valaparser.vala b/vala/valaparser.vala
index 507464566..34e45db81 100644
--- a/vala/valaparser.vala
+++ b/vala/valaparser.vala
@@ -983,6 +983,9 @@ public class Vala.Parser : CodeVisitor {
                        foreach (Expression size in size_specifier_list) {
                                expr.append_size (size);
                        }
+               } else if (initializer == null) {
+                       Report.warning (src, "possibly missing array size");
+                       throw new ParseError.SYNTAX ("expected array initializer list");
                }
                return expr;
        }