From 013cf5d6618f7fa5cb210fd2692f14fb01e59ee0 Mon Sep 17 00:00:00 2001
From: Nick Fitzgerald <fitzgen@gmail.com>
Date: Wed, 29 May 2024 11:17:33 -0700
Subject: [PATCH] Test `return_call*`s to callees that return more values than
 the caller does

While a `call $f; return` sequence where `$f` returns more values than its
caller is valid so long as the tail of `$f`'s returns match the caller's
returns, however that situation is not valid for `return_call $f`. Tail callees
must return the exact same number of results as the caller, not more. This case
was not previously exercised in any of the spec tests.

Procedural note: I am adding all these tests to the function-references proposal
to avoid needing to make multiple PRs to multiple repos because
`return_call_ref` was not introduced until this proposal.
---
 test/core/return_call.wast          | 10 +++++++++-
 test/core/return_call_indirect.wast | 12 +++++++++++-
 test/core/return_call_ref.wast      | 11 +++++++++++
 3 files changed, 31 insertions(+), 2 deletions(-)

diff --git a/test/core/return_call.wast b/test/core/return_call.wast
index 2f91f4de..b9e8f8f0 100644
--- a/test/core/return_call.wast
+++ b/test/core/return_call.wast
@@ -188,7 +188,15 @@
   )
   "type mismatch"
 )
-
+(assert_invalid
+  (module
+    (func $f (result i32 i32) unreachable)
+    (func (result i32)
+      return_call $f
+    )
+  )
+  "type mismatch"
+)
 
 ;; Unbound function
 
diff --git a/test/core/return_call_indirect.wast b/test/core/return_call_indirect.wast
index acf0a72e..aa158be2 100644
--- a/test/core/return_call_indirect.wast
+++ b/test/core/return_call_indirect.wast
@@ -508,7 +508,17 @@
   )
   "type mismatch"
 )
-
+(assert_invalid
+  (module
+    (type $ty (func (result i32 i32)))
+    (import "env" "table" (table $table 0 funcref))
+    (func (param i32) (result i32)
+      local.get 0
+      return_call_indirect $table (type $ty)
+    )
+  )
+  "type mismatch"
+)
 
 ;; Unbound type
 
diff --git a/test/core/return_call_ref.wast b/test/core/return_call_ref.wast
index 2b495f46..327dc84b 100644
--- a/test/core/return_call_ref.wast
+++ b/test/core/return_call_ref.wast
@@ -374,3 +374,14 @@
   )
   "type mismatch"
 )
+
+(assert_invalid
+  (module
+    (type $ty (func (result i32 i32)))
+    (func (param funcref) (result i32)
+      local.get 0
+      return_call_ref $ty
+    )
+  )
+  "type mismatch"
+)