Bring no-std-check into the main workspace

Cargo.toml

@@ -12,12 +12,12 @@ members = [
     "pbt-gen",
     "proto",
     "rpc",
-    "testgen"
+    "testgen",
+    "tools/no-std-check"
 ]
 
 exclude = [
     "proto-compiler",
-    "tools/no-std-check"
 ]
 
 [profile.release.package.cometbft-light-client-js]

tools/no-std-check/Cargo.toml

@@ -28,3 +28,7 @@ substrate-std = [
   "sp-runtime/std",
   "sp-std/std",
 ]
+
+[[example]]
+name = "no_std"
+crate-type = ["lib"]

tools/no-std-check/Makefile

@@ -5,29 +5,29 @@ setup:
 	rustup target add wasm32-unknown-unknown --toolchain $(NIGHTLY_VERSION)
 
 build-substrate:
-	cargo build \
+	cargo build --examples \
 		--no-default-features \
 		--features use-substrate,substrate-std
 
 check-panic-conflict:
-	cargo build \
+	cargo build --examples \
 		--no-default-features \
 		--features panic-handler
 
 check-cargo-build-std:
 	rustup run $(NIGHTLY_VERSION) -- \
-		cargo build -Z build-std=core,alloc \
+		cargo build --examples -Z build-std=core,alloc \
 		--no-default-features \
 		--target x86_64-unknown-linux-gnu
 
 check-wasm:
 	rustup run $(NIGHTLY_VERSION) -- \
-		cargo build \
+		cargo build --examples \
 		--target wasm32-unknown-unknown
 
 check-substrate:
 	rustup run $(NIGHTLY_VERSION) -- \
-		cargo build \
+		cargo build --examples \
 		--no-default-features \
 		--features use-substrate \
 		--target wasm32-unknown-unknown

tools/no-std-check/examples/no_std.rs

@@ -0,0 +1,49 @@
+#![no_std]
+#![allow(unused_imports)]
+
+extern crate alloc;
+
+// Import the crates that we want to check if they are fully no-std compliance
+
+use cometbft;
+use cometbft_light_client_verifier;
+use cometbft_proto;
+
+#[cfg(feature = "sp-core")]
+use sp_core;
+
+#[cfg(feature = "sp-io")]
+use sp_io;
+
+#[cfg(feature = "sp-runtime")]
+use sp_runtime;
+
+#[cfg(feature = "sp-std")]
+use sp_std;
+
+use core::panic::PanicInfo;
+
+/*
+
+This function definition checks for the compliance of no-std in
+dependencies by causing a compile error if  this crate is
+linked with `std`. When that happens, you should see error messages
+such as follows:
+
+```
+error[E0152]: found duplicate lang item `panic_impl`
+  --> no-std-check/src/lib.rs
+   |
+12 | fn panic(_info: &PanicInfo) -> ! {
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: the lang item is first defined in crate `std` (which `offending-crate` depends on)
+```
+
+ */
+#[cfg(feature = "panic-handler")]
+#[panic_handler]
+#[no_mangle]
+fn panic(_info: &PanicInfo) -> ! {
+    loop {}
+}

tools/no-std-check/src/lib.rs

@@ -1,50 +1,5 @@
-// ensure_no_std/src/main.rs
-#![no_std]
-#![allow(unused_imports)]
-
-extern crate alloc;
-
-// Import the crates that we want to check if they are fully no-std compliance
-
-use cometbft;
-use cometbft_light_client_verifier;
-use cometbft_proto;
-
-#[cfg(feature = "sp-core")]
-use sp_core;
-
-#[cfg(feature = "sp-io")]
-use sp_io;
-
-#[cfg(feature = "sp-runtime")]
-use sp_runtime;
-
-#[cfg(feature = "sp-std")]
-use sp_std;
-
-use core::panic::PanicInfo;
-
-/*
-
-This function definition checks for the compliance of no-std in
-dependencies by causing a compile error if  this crate is
-linked with `std`. When that happens, you should see error messages
-such as follows:
-
-```
-error[E0152]: found duplicate lang item `panic_impl`
-  --> no-std-check/src/lib.rs
-   |
-12 | fn panic(_info: &PanicInfo) -> ! {
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: the lang item is first defined in crate `std` (which `offending-crate` depends on)
-```
-
- */
-#[cfg(feature = "panic-handler")]
-#[panic_handler]
-#[no_mangle]
-fn panic(_info: &PanicInfo) -> ! {
-    loop {}
-}
+// This is a dummy library source.
+//
+// The check against linkage with std is performed in an example target.
+// This allows us to include this crate in the main workspace and have
+// `cargo test` build the example without the test harness, which requires std.