fix(ext/ffi): disallow empty ffi structs (#17487)

This patch makes `NativeType` to `libffi::middle::Type` conversion
failliable and w.t disallows struct with empty fields. libffi does not
handle "empty" struct because they don't exist in C (or Rust).

Fixes #17481

1 files changed, 35 insertions, 1 deletions

diff --git a/test_ffi/tests/test.js b/test_ffi/tests/test.js
index 0ada7dc0a..e45c5895b 100644
--- a/test_ffi/tests/test.js
+++ b/test_ffi/tests/test.js
@@ -37,6 +37,40 @@ assertThrows(
   "Failed to register symbol non_existent_symbol",
 );
 
+assertThrows(() => {
+  Deno.dlopen(libPath, {
+    print_something: {
+      parameters: [],
+      result: { struct: [] }
+    },
+  }),
+  TypeError,
+  "Struct must have at least one field"
+});
+
+assertThrows(() => {
+  Deno.dlopen(libPath, {
+    print_something: {
+      parameters: [ { struct: [] } ],
+      result: "void",
+    },
+  }),
+  TypeError,
+  "Struct must have at least one field"
+});
+
+const Empty = { struct: [] }
+assertThrows(() => {
+  Deno.dlopen(libPath, {
+    print_something: {
+      parameters: [ { struct: [Empty] } ],
+      result: "void",
+    },
+  }),
+  TypeError,
+  "Struct must have at least one field"
+});
+
 const Point = ["f64", "f64"];
 const Size = ["f64", "f64"];
 const Rect = ["f64", "f64", "f64", "f64"];
@@ -720,4 +754,4 @@ function testOptimized(fn, callback) {
     console.log(r2);
   }
   assertIsOptimized(fn);
-}
\ No newline at end of file
+}