refactor: fully-remove cfg-ignored items (#53)

Other refactors:
* Fix name `GenFinalPubVistor` -> `GenFinalPubVisitor`
* Unify handling of `#[cfg(stageleft_runtime)]` attribute
* Unify handling of `pub` re-exports

Author: MingweiSamuel

Cargo.lock

@@ -16,3 +16,6 @@ slotmap = "1.0.0"
 
 [build-dependencies]
 stageleft_tool = { path = "../stageleft_tool", version = "^0.12.0" }
+
+[dev-dependencies]
+insta = "1.39"

stageleft_test_no_entry/Cargo.toml

@@ -16,4 +16,14 @@ fn splitbrain(st: SplitbrainStruct) {
 pub struct SplitbrainStruct {
     /// This stays as regular `MyKey` (equiv. to `crate::MyKey`).
     my_key: MyKey,
-}
+}
+
+#[cfg(stageleft_runtime)]
+#[expect(dead_code)]
+struct ThisShouldBeRemoved;
+
+pub mod pub_mod {
+    #[cfg(stageleft_runtime)]
+    #[expect(dead_code)]
+    struct ThisShouldAlsoBeRemoved;
+}

stageleft_test_no_entry/src/lib.rs

@@ -0,0 +1,17 @@
+#[test]
+fn test_lib_pub() {
+    insta::assert_snapshot!(include_str!(concat!(
+        env!("OUT_DIR"),
+        stageleft::PATH_SEPARATOR!(),
+        "lib_pub.rs"
+    )));
+}
+
+#[test]
+fn test_staged_deps() {
+    insta::assert_snapshot!(include_str!(concat!(
+        env!("OUT_DIR"),
+        stageleft::PATH_SEPARATOR!(),
+        "staged_deps.rs"
+    )));
+}

stageleft_test_no_entry/tests/codegen_snapshot.rs

@@ -0,0 +1,15 @@
+---
+source: stageleft_test_no_entry/tests/codegen_snapshot.rs
+expression: "include_str!(concat!(env!(\"OUT_DIR\"), stageleft::PATH_SEPARATOR!(),\n\"lib_pub.rs\"))"
+---
+pub use crate::MyKey;
+/// Test that `stageleft::export` prevents splitbrain of `MyKey` type.
+#[allow(dead_code)]
+pub fn splitbrain(st: SplitbrainStruct) {
+    let _key: MyKey = st.my_key;
+}
+pub use crate::SplitbrainStruct;
+
+pub mod pub_mod {
+
+}

stageleft_test_no_entry/tests/snapshots/codegen_snapshot__lib_pub.snap

@@ -0,0 +1,37 @@
+---
+source: stageleft_test_no_entry/tests/codegen_snapshot.rs
+assertion_line: 12
+expression: "include_str!(concat!(env!(\"OUT_DIR\"), stageleft::PATH_SEPARATOR!(),\n\"staged_deps.rs\"))"
+---
+pub mod __deps {
+    pub use stageleft;
+    pub use slotmap;
+    #[stageleft::internal::ctor::ctor(crate_path = stageleft::internal::ctor)]
+    fn __init() {
+        stageleft::internal::add_deps_reexport(
+            vec!["stageleft"],
+            vec![
+                option_env!("STAGELEFT_FINAL_CRATE_NAME")
+                    .unwrap_or(env!("CARGO_PKG_NAME"))
+                    .replace("-", "_"),
+                "__staged".to_string(),
+                "__deps".to_string(),
+                "stageleft".to_string(),
+            ],
+        );
+        stageleft::internal::add_deps_reexport(
+            vec!["slotmap"],
+            vec![
+                option_env!("STAGELEFT_FINAL_CRATE_NAME")
+                    .unwrap_or(env!("CARGO_PKG_NAME"))
+                    .replace("-", "_"),
+                "__staged".to_string(),
+                "__deps".to_string(),
+                "slotmap".to_string(),
+            ],
+        );
+        stageleft::internal::add_crate_with_staged(
+            env!("CARGO_PKG_NAME").replace("-", "_"),
+        );
+    }
+}