[lang] Add test framework and add noop contract test

lang/src/lib.rs

@@ -37,6 +37,9 @@ mod hir;
 mod ident_ext;
 mod parser;
 
+#[cfg(test)]
+mod tests;
+
 use errors::Result;
 
 /// Simple wrapper from `proc_macro` to `proc_macro2` and back again.
@@ -52,16 +55,10 @@ fn contract_gen_impl(input: proc_macro::TokenStream) -> Result<proc_macro::Token
 
 /// Parses the given token stream as pDSL contract, performs some checks and returns
 /// the corresponding contract as token stream.
-fn contract_gen_impl2(input: proc_macro2::TokenStream) -> Result<proc_macro2::TokenStream> {
+pub(crate) fn contract_gen_impl2(input: proc_macro2::TokenStream) -> Result<proc_macro2::TokenStream> {
     let ast_contract = parser::parse_contract(input.clone())?;
     let hir_contract = hir::Contract::from_ast(&ast_contract)?;
     // gen::gir::generate(&hir_program)?;
     let tokens = gen::codegen(&hir_contract);
     Ok(tokens.into())
 }
-
-#[test]
-fn empty_contract_input() {
-    use quote::quote;
-    assert!(contract_gen_impl2(quote!{}).is_err());
-}

lang/src/tests/mod.rs

+mod utils;
+mod noop;
+
+pub(crate) use quote::quote;
+pub(crate) use utils::assert_eq_tokenstreams;
+pub(crate) use crate::contract_gen_impl2;
+
+#[test]
+fn empty_contract_input() {
+    assert!(contract_gen_impl2(quote!{}).is_err());
+}

lang/src/tests/noop.rs

+use super::*;
+
+#[test]
+fn noop_contract() {
+    assert_eq_tokenstreams(
+        quote!{
+            /// The contract that does nothing.
+            ///
+            /// # Note
+            ///
+            /// Can be deployed, cannot be called.
+            struct Noop {}
+
+            impl Deploy for Noop {
+                /// Does nothing to initialize itself.
+                fn deploy(&mut self) {}
+            }
+
+            /// Provides no way to call it as extrinsic.
+            impl Noop {}
+        },
+        quote!{
+            pdsl_model::state! {
+                /// The contract that does nothing.
+                ///
+                /// # Note
+                ///
+                /// Can be deployed, cannot be called.
+                struct Noop {}
+            }
+
+            use pdsl_model::messages;
+            pdsl_model::messages! {}
+
+            impl Noop {
+                /// Does nothing to initialize itself.
+                pub fn deploy(&mut self, env: &mut pdsl_model::EnvHandler) { }
+            }
+
+            impl Noop {}
+
+            use pdsl_model::Contract;
+            fn instantiate() -> impl pdsl_model::Contract {
+                pdsl_model::ContractDecl::using::<Noop>()
+                    .on_deploy(|env, ()| {
+                        let (handler, state) = env.split_mut();
+                        state.deploy(handler,)
+                    })
+                    .instantiate()
+            }
+
+            #[no_mangle] fn deploy() { instantiate().deploy() }
+            #[no_mangle] fn call() { instantiate().dispatch() }
+        }
+    )
+}

lang/src/tests/utils.rs

+use crate::contract_gen_impl2;
+
+pub fn assert_eq_tokenstreams(
+    input: proc_macro2::TokenStream,
+    expected: proc_macro2::TokenStream,
+) {
+    assert_eq!(
+        contract_gen_impl2(input)
+            .map(|result| result.to_string())
+            .map_err(|err| err.to_string()),
+        Ok(expected.to_string())
+    )
+}