Factor array size vs Rust derive limit checking into a common method

We were copying it around and it will be easier if it is defined in one place.

1 files changed, 14 insertions, 15 deletions

diff --git a/src/ir/layout.rs b/src/ir/layout.rs
index 298fe54a..2df15ef2 100644
--- a/src/ir/layout.rs
+++ b/src/ir/layout.rs
@@ -104,44 +104,43 @@ impl Opaque {
             None
         }
     }
-}
 
-impl CanTriviallyDeriveDebug for Opaque {
-    fn can_trivially_derive_debug(&self) -> bool {
+    /// Return `true` if this opaque layout's array size will fit within the
+    /// maximum number of array elements that Rust allows deriving traits
+    /// with. Return `false` otherwise.
+    pub fn array_size_within_derive_limit(&self) -> bool {
         self.array_size().map_or(false, |size| {
             size <= RUST_DERIVE_IN_ARRAY_LIMIT
         })
     }
 }
 
+impl CanTriviallyDeriveDebug for Opaque {
+    fn can_trivially_derive_debug(&self) -> bool {
+        self.array_size_within_derive_limit()
+    }
+}
+
 impl CanTriviallyDeriveDefault for Opaque {
     fn can_trivially_derive_default(&self) -> bool {
-        self.array_size().map_or(false, |size| {
-            size <= RUST_DERIVE_IN_ARRAY_LIMIT
-        })
+        self.array_size_within_derive_limit()
     }
 }
 
 impl CanTriviallyDeriveCopy for Opaque {
     fn can_trivially_derive_copy(&self) -> bool {
-        self.array_size().map_or(false, |size| {
-            size <= RUST_DERIVE_IN_ARRAY_LIMIT
-        })
+        self.array_size_within_derive_limit()
     }
 }
 
 impl CanTriviallyDeriveHash for Opaque {
     fn can_trivially_derive_hash(&self) -> bool {
-        self.array_size().map_or(false, |size| {
-            size <= RUST_DERIVE_IN_ARRAY_LIMIT
-        })
+        self.array_size_within_derive_limit()
     }
 }
 
 impl CanTriviallyDerivePartialEqOrPartialOrd for Opaque {
     fn can_trivially_derive_partialeq_or_partialord(&self) -> bool {
-        self.array_size().map_or(false, |size| {
-            size <= RUST_DERIVE_IN_ARRAY_LIMIT
-        })
+        self.array_size_within_derive_limit()
     }
 }