add composability for general import (#1380)

crates/wasm-compose/src/composer.rs

@@ -407,15 +407,7 @@ impl<'a> CompositionGraphBuilder<'a> {
         let count = queue.len();
 
         // Push a dependency for every instance import
-        'outer: for (import, name, ty) in component.imports() {
-            match ty {
-                ComponentTypeRef::Instance(_) => {}
-                _ => bail!(
-                    "component `{path}` has a non-instance import named `{name}`",
-                    path = component.path().unwrap().display()
-                ),
-            }
-
+        'outer: for (import, name, _) in component.imports() {
             log::debug!("adding dependency for argument `{name}` (import index {import}) from instance `{instance_name}` to the queue", import = import.0);
 
             // Search for a matching definition export for this import

crates/wasm-compose/tests/compositions/not-instance-import/b.wat

@@ -0,0 +1,3 @@
+(component
+  (instance)
+)

crates/wasm-compose/tests/compositions/not-instance-import/composed.wat

@@ -0,0 +1,21 @@
+(component
+  (type (;0;) (func))
+  (import "a" (func (;0;) (type 0)))
+  (component (;0;)
+    (type (;0;) (func))
+    (import "a" (func (;0;) (type 0)))
+    (type (;1;)
+      (instance)
+    )
+    (import "locked-dep=<foo:add@1.0.0>" (instance (;0;) (type 1)))
+  )
+  (component (;1;)
+    (instance (;0;))
+  )
+  (instance (;0;) (instantiate 1))
+  (instance (;1;) (instantiate 0
+      (with "locked-dep=<foo:add@1.0.0>" (instance 0))
+      (with "a" (func 0))
+    )
+  )
+)

crates/wasm-compose/tests/compositions/not-instance-import/config.yml

@@ -0,0 +1,6 @@
+instantiations:
+  root:
+    arguments:
+      locked-dep=<foo:add@1.0.0>: a1
+  a1:
+    dependency: b

crates/wasm-compose/tests/compositions/not-instance-import/root.wat

@@ -1,3 +1,4 @@
 (component
   (import "a" (func))
+  (import "locked-dep=<foo:add@1.0.0>" (instance))
 )