Register module signatures (#811)

crates/api/tests/invoke_func_via_table.rs

@@ -0,0 +1,33 @@
+use anyhow::{Context as _, Result};
+use wasmtime::*;
+
+#[test]
+fn test_invoke_func_via_table() -> Result<()> {
+    let store = Store::default();
+
+    let binary = wat::parse_str(
+        r#"
+          (module
+            (func $f (result i64) (i64.const 42))
+
+            (table (export "table") 1 1 anyfunc)
+            (elem (i32.const 0) $f)
+          )
+        "#,
+    )?;
+    let module = Module::new(&store, &binary).context("> Error compiling module!")?;
+    let instance = Instance::new(&store, &module, &[]).context("> Error instantiating module!")?;
+
+    let f = instance
+        .find_export_by_name("table")
+        .unwrap()
+        .table()
+        .unwrap()
+        .get(0)
+        .funcref()
+        .unwrap()
+        .clone();
+    let result = f.call(&[]).unwrap();
+    assert_eq!(result[0].unwrap_i64(), 42);
+    Ok(())
+}