From e6344677fe8e370974c47cc96e75b632e0099097 Mon Sep 17 00:00:00 2001
From: bill fumerola <bill@andyl.com>
Date: Thu, 26 Jun 2025 12:48:36 -0700
Subject: [PATCH] chore(test): add test for duplicate package insert

---
 Cargo.lock   |  1 +
 Cargo.toml   |  4 ++++
 src/graph.rs | 44 ++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 49 insertions(+)

diff --git a/Cargo.lock b/Cargo.lock
index ee9bde1..6548026 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1044,6 +1044,7 @@ dependencies = [
  "snafu",
  "wac-types",
  "wasmtime",
+ "wat",
 ]
 
 [[package]]
diff --git a/Cargo.toml b/Cargo.toml
index 89bcd8d..28e807b 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -39,6 +39,7 @@ anyhow = "1"
 derivative = "2"
 semver = "1"
 wasmtime = { version = "34", default-features = false }
+wat = { version = "1.233.0", default-features = false }
 wit-bindgen = { version = "0.43", default-features = false, features = [
   "macros",
 ]}
@@ -57,3 +58,6 @@ wasmtime = { workspace = true, features = [
   "cranelift",
   "wat",
 ]}
+
+[dev-dependencies]
+wat.workspace = true
diff --git a/src/graph.rs b/src/graph.rs
index 8f84f14..33ce52c 100644
--- a/src/graph.rs
+++ b/src/graph.rs
@@ -779,3 +779,47 @@ pub enum InstantiatePackageError {
     #[snafu(display("Missing interface export {}", path))]
     MissingInterfaceExport { path: ForeignInterfacePath },
 }
+
+#[cfg(test)]
+mod tests {
+    // Simple async trampoline that just passes calls through
+
+    use std::sync::Arc;
+
+    struct PassthroughTrampoline;
+    impl crate::Trampoline<(), ()> for PassthroughTrampoline {
+        fn bounce<'c>(
+            &self,
+            mut _call: crate::GuestCall<'c, (), ()>,
+        ) -> Result<crate::GuestResult<'c, (), ()>, anyhow::Error> {
+            todo!()
+        }
+    }
+
+    #[test]
+    fn test_add_duplicate_package() {
+        const VERSION: semver::Version = semver::Version::new(1, 0, 0);
+        let pkg = || {
+            let trampoline: Arc<dyn crate::Trampoline<(), ()>> = Arc::new(PassthroughTrampoline {});
+            crate::PackageTrampoline::with_default_context(trampoline, ())
+        };
+        let mut graph = crate::CompositionGraph::<()>::new();
+        let test_component = wat::parse_str(
+            r#"
+(component
+  (core module (;0;)
+    (memory (;0;) 16)
+    (export "memory" (memory 0))
+  )
+)"#,
+        )
+        .unwrap();
+
+        graph
+            .add_package("test".to_string(), VERSION, test_component.clone(), pkg())
+            .expect("Failed to add package");
+        graph
+            .add_package("test".to_string(), VERSION, test_component, pkg())
+            .expect_err("Expected to fail adding duplicate package");
+    }
+}