Add check for subscript operator return type (#7244)

Fixes #6987

1 files changed, 32 insertions, 0 deletions

diff --git a/tests/diagnostics/subscript-missing-return-type.slang b/tests/diagnostics/subscript-missing-return-type.slang
new file mode 100644
index 000000000..23c2cda5e
--- /dev/null
+++ b/tests/diagnostics/subscript-missing-return-type.slang
@@ -0,0 +1,32 @@
+// Test that __subscript without return type produces proper error message
+
+//TEST:SIMPLE(filecheck=CHECK): -target spirv
+
+struct MyType
+{
+    int val[12];
+    
+    // CHECK: ([[# @LINE+1]]): error 30901: __subscript declaration must have a return type specified after '->'
+    __subscript(int x, int y)
+    {
+        get { return val[x*3 + y]; }
+    }
+}
+
+// This should compile fine - subscript with return type
+struct MyType2
+{
+    int val[12];
+    __subscript(int x, int y) -> int
+    {
+        get { return val[x*3 + y]; }
+    }
+}
+
+[shader("compute")]
+[numthreads(1,1,1)]
+void computeMain()
+{
+    MyType2 obj;
+    int v = obj[1, 2];
+} 
\ No newline at end of file