feat: Investigate Test Coverage Drop

.github/workflows/test.yml

@@ -117,16 +117,19 @@ jobs:
     #
     # for lots of more discussion.
     runs-on: ubuntu-latest
-    name: ubuntu / stable / coverage
+    name: ubuntu / nightly / coverage
     steps:
       - uses: actions/checkout@v4
         with:
           submodules: true
 
       - name: Install rust
+        # We run in nightly to make use of the `#[coverage(off)]` attribute (see _contracts/src/lib.rs_)
+        # We'll return to stable release after the tracking issue is merged (and the feature is stable)
+        # See: https://github.com/rust-lang/rust/issues/84605
         uses: actions-rust-lang/setup-rust-toolchain@v1
         with:
-          toolchain: stable
+          toolchain: nightly
           components: llvm-tools-preview
           rustflags: ""
 

Cargo.toml

@@ -65,6 +65,7 @@ version = "0.2.0-alpha.1"
 missing_docs = "warn"
 unreachable_pub = "warn"
 rust_2021_compatibility = { level = "warn", priority = -1 }
+unexpected_cfgs = { level = "warn", check-cfg = ['cfg(coverage_nightly)'] }
 
 [workspace.lints.clippy]
 pedantic = "warn"

contracts/src/lib.rs

@@ -46,6 +46,7 @@ impl MyContract { }
 )]
 #![cfg_attr(not(feature = "std"), no_std, no_main)]
 #![deny(rustdoc::broken_intra_doc_links)]
+#![cfg_attr(coverage_nightly, feature(coverage_attribute))]
 extern crate alloc;
 
 pub mod access;