Exclude AsRef<Path> for no-std builds

And test no-std in CI.

Author: bluss

.github/workflows/ci.yml

@@ -54,6 +54,28 @@ jobs:
         if: matrix.bench != ''
         run: cargo test -v --benches
 
+  nostd:
+    runs-on: ubuntu-latest
+    continue-on-error: false
+    strategy:
+      matrix:
+        include:
+          - rust: stable
+            target: thumbv6m-none-eabi
+            features: zeroize
+
+    name: nostd/${{ matrix.target }}/${{ matrix.rust }}
+    steps:
+      - uses: actions/checkout@v4
+      - uses: dtolnay/rust-toolchain@stable
+        with:
+          toolchain: ${{ matrix.rust }}
+          targets: ${{ matrix.target }}
+      - name: Tests
+        run: |
+          cargo rustc "--target=${{ matrix.target }}" --no-default-features --features "${{ matrix.features }}"
+
+
   miri:
     runs-on: ubuntu-latest
     steps:

src/array_string.rs

@@ -5,6 +5,7 @@ use std::fmt;
 use std::hash::{Hash, Hasher};
 use std::mem::MaybeUninit;
 use std::ops::{Deref, DerefMut};
+#[cfg(feature="std")]
 use std::path::Path;
 use std::ptr;
 use std::slice;
@@ -502,6 +503,7 @@ impl<const CAP: usize> fmt::Debug for ArrayString<CAP>
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { (**self).fmt(f) }
 }
 
+#[cfg(feature="std")]
 impl<const CAP: usize> AsRef<Path> for ArrayString<CAP> {
     fn as_ref(&self) -> &Path {
         self.as_str().as_ref()