Add no_std_lib test lib

.github/workflows/rust.yml

@@ -29,6 +29,10 @@ jobs:
       run: |
         cd tests-extra
         cargo test --features=invalid_programs --verbose
+    - name: Run tests-extra no_std_lib
+      run: |
+        cd tests-extra/no_std_lib
+        cargo test --verbose
     - name: Run examples
       run: |
         cd examples
@@ -71,6 +75,9 @@ jobs:
         rustup component add miri
       shell: bash
 
+    - name: Run tests with nightly basic
+      run: |
+        cargo test --verbose
     - name: Run tests x86_64-unknown-linux-gnu
       run: |
         cargo miri test --verbose --target x86_64-unknown-linux-gnu

tests-extra/no_std_lib/Cargo.toml

@@ -0,0 +1,10 @@
+[package]
+name = "no_std_lib"
+version = "0.1.0"
+authors = ["Lukas Bergdoll <[email protected]>"]
+edition = "2018"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+self_cell = { path = "../.." }

tests-extra/no_std_lib/src/lib.rs

@@ -0,0 +1,59 @@
+#![no_std]
+
+use self_cell::self_cell;
+
+// Not using alloc is on purpose, self_cell should also work in such scenarios.
+
+const SCRATCH_REGION: [u8; 4096] = [0u8; 4096];
+
+#[derive(Eq, PartialEq)]
+struct StaticString {
+    region: &'static [u8],
+}
+
+const MAX_NODES: usize = 8;
+
+#[derive(Eq, PartialEq)]
+struct Ast<'a>([Option<&'a [u8]>; MAX_NODES]);
+
+self_cell!(
+    struct AstCell {
+        owner: StaticString,
+
+        #[covariant]
+        dependent: Ast,
+    }
+
+    impl {Eq, PartialEq}
+);
+
+fn build_ast_cell() -> AstCell {
+    // Yes in a static setting self_cell is not terribly useful, this could be solved differently.
+    // This is only a test.
+    let pre_processed_code = StaticString {
+        region: &SCRATCH_REGION[4000..4015],
+    };
+
+    AstCell::new(pre_processed_code, |code| {
+        let mut ast_nodes = [None; MAX_NODES];
+        ast_nodes[0] = Some(&code.region[3..7]);
+        ast_nodes[1] = Some(&code.region[10..12]);
+
+        Ast(ast_nodes)
+    })
+}
+
+#[test]
+fn self_cell_works_in_no_std_env() {
+    let ast_cell = build_ast_cell();
+    assert_eq!(ast_cell.borrow_owner().region.len(), 15);
+    assert_eq!(
+        ast_cell
+            .borrow_dependent()
+            .0
+            .iter()
+            .filter(|val| val.is_some())
+            .count(),
+        2
+    );
+}