Merge pull request #275 from quartiq/keylookup-named-len-check

KeyLookup: ensure at least one child in Named
quartiq · Feb 4, 2025 · 23fc746 · 23fc746
2 parents 5279641 + 6088508
commit 23fc746
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Showing 3 changed files with 17 additions and 8 deletions.
diff --git a/miniconf/src/impls.rs b/miniconf/src/impls.rs
@@ -237,7 +237,7 @@ impl<T: TreeAny> TreeAny for Option<T> {
 
 /////////////////////////////////////////////////////////////////////////////////////////
 
-const RESULT_LOOKUP: KeyLookup = KeyLookup::Named(&["Ok", "Err"]);
+const RESULT_LOOKUP: KeyLookup = KeyLookup::named(&["Ok", "Err"]);
 
 impl<T: TreeKey, E: TreeKey> TreeKey for Result<T, E> {
     #[inline]
@@ -319,7 +319,7 @@ impl<T: TreeAny, E: TreeAny> TreeAny for Result<T, E> {
 
 /////////////////////////////////////////////////////////////////////////////////////////
 
-const BOUND_LOOKUP: KeyLookup = KeyLookup::Named(&["Included", "Excluded"]);
+const BOUND_LOOKUP: KeyLookup = KeyLookup::named(&["Included", "Excluded"]);
 
 impl<T: TreeKey> TreeKey for Bound<T> {
     #[inline]
@@ -400,7 +400,7 @@ impl<T: TreeAny> TreeAny for Bound<T> {
 
 /////////////////////////////////////////////////////////////////////////////////////////
 
-const RANGE_LOOKUP: KeyLookup = KeyLookup::Named(&["start", "end"]);
+const RANGE_LOOKUP: KeyLookup = KeyLookup::named(&["start", "end"]);
 
 impl<T: TreeKey> TreeKey for Range<T> {
     #[inline]
@@ -517,7 +517,7 @@ impl<T: TreeSerialize> TreeSerialize for RangeInclusive<T> {
 
 /////////////////////////////////////////////////////////////////////////////////////////
 
-const RANGE_FROM_LOOKUP: KeyLookup = KeyLookup::Named(&["start"]);
+const RANGE_FROM_LOOKUP: KeyLookup = KeyLookup::named(&["start"]);
 
 impl<T: TreeKey> TreeKey for RangeFrom<T> {
     #[inline]
@@ -594,7 +594,7 @@ impl<T: TreeAny> TreeAny for RangeFrom<T> {
 
 /////////////////////////////////////////////////////////////////////////////////////////
 
-const RANGE_TO_LOOKUP: KeyLookup = KeyLookup::Named(&["end"]);
+const RANGE_TO_LOOKUP: KeyLookup = KeyLookup::named(&["end"]);
 
 impl<T: TreeKey> TreeKey for RangeTo<T> {
     #[inline]

diff --git a/miniconf/src/key.rs b/miniconf/src/key.rs
@@ -18,7 +18,16 @@ pub enum KeyLookup {
 }
 
 impl KeyLookup {
-    /// Return a homogenenous unnamed KeyLookup
+    /// Return a named KeyLookup
+    #[inline]
+    pub const fn named(names: &'static [&'static str]) -> Self {
+        if names.is_empty() {
+            panic!("Must have at least one child");
+        }
+        Self::Named(names)
+    }
+
+    /// Return a homogenenous, unnamed KeyLookup
     #[inline]
     pub const fn homogeneous(len: usize) -> Self {
         match NonZero::new(len) {
@@ -27,7 +36,7 @@ impl KeyLookup {
         }
     }
 
-    /// Return a homogenenous unnamed KeyLookup
+    /// Return a heterogeneous numbered KeyLookup
     #[inline]
     pub const fn numbered(len: usize) -> Self {
         match NonZero::new(len) {

diff --git a/miniconf_derive/src/tree.rs b/miniconf_derive/src/tree.rs
@@ -217,7 +217,7 @@ impl Tree {
                     },
                 )
             },
-            Some(names) => quote!(::miniconf::KeyLookup::Named(&[#(#names ,)*])),
+            Some(names) => quote!(::miniconf::KeyLookup::named(&[#(#names ,)*])),
         };
         let traverse_arms = fields.iter().enumerate().map(|(i, f)| f.traverse_by_key(i));
         let index = self.index();