chore(ci): Treat clippy warnings as errors in CI

.github/workflows/formatting.yml

@@ -17,7 +17,9 @@ jobs:
     name: cargo clippy
     runs-on: ${{ matrix.runner }}
     timeout-minutes: 30
-
+    env:
+      RUSTFLAGS: -Dwarnings
+
     strategy:
       fail-fast: false
       matrix:
@@ -30,9 +32,8 @@ jobs:
         uses: actions/checkout@v4
 
       - name: Setup toolchain
-        uses: dtolnay/rust-toolchain@master
+        uses: dtolnay/rust-toolchain@1.66.0
         with:
-          toolchain: stable # We do not use MSRV so we can benefit from newer lints
           targets: ${{ matrix.target }}
           components: clippy, rustfmt
 

compiler/noirc_frontend/src/hir/def_map/mod.rs

@@ -160,15 +160,15 @@ impl CrateDefMap {
             .iter()
             .filter_map(|(id, module)| {
                 if module.is_contract {
-                    let function_ids: Vec<FuncId> =
-                        module.value_definitions().filter_map(|id| id.as_function()).collect();
-
-                    let functions = function_ids
-                        .into_iter()
-                        .map(|id| {
-                            let is_entry_point =
-                                !interner.function_attributes(&id).has_contract_library_method();
-                            ContractFunctionMeta { function_id: id, is_entry_point }
+                    let functions = module
+                        .value_definitions()
+                        .filter_map(|id| {
+                            id.as_function().map(|function_id| {
+                                let is_entry_point = !interner
+                                    .function_attributes(&function_id)
+                                    .has_contract_library_method();
+                                ContractFunctionMeta { function_id, is_entry_point }
+                            })
                         })
                         .collect();
 

compiler/noirc_frontend/src/hir/type_check/mod.rs

@@ -397,8 +397,9 @@ mod test {
     }
 
     fn type_check_src_code(src: &str, func_namespace: Vec<String>) {
-        type_check_src_code_errors_expected(src, 0, func_namespace)
+        type_check_src_code_errors_expected(src, 0, func_namespace);
     }
+
     // This function assumes that there is only one function and this is the
     // func id that is returned
     fn type_check_src_code_errors_expected(

compiler/noirc_frontend/src/node_interner.rs

@@ -549,7 +549,7 @@ impl NodeInterner {
     }
 
     pub fn function_attributes(&self, func_id: &FuncId) -> Attributes {
-        self.function_meta(func_id).attributes.clone()
+        self.function_meta(func_id).attributes
     }
 
     /// Returns the interned statement corresponding to `stmt_id`