pr: do not use serde_with

Author: brooksprumo

Cargo.lock

@@ -46,7 +46,6 @@ regex = { workspace = true }
 serde = { workspace = true, features = ["rc"] }
 serde_derive = { workspace = true }
 serde_json = { workspace = true }
-serde_with = { workspace = true }
 solana-accounts-db = { workspace = true }
 solana-address-lookup-table-program = { workspace = true }
 solana-bpf-loader-program = { workspace = true }

programs/sbf/Cargo.lock

@@ -1,9 +1,48 @@
+use {
+    serde::{de, Deserialize, Deserializer},
+    std::{fmt, marker::PhantomData},
+};
+
 /// Snapshot serde-safe AccountsLtHash
 #[cfg_attr(feature = "frozen-abi", derive(AbiExample))]
-#[serde_with::serde_as]
-#[derive(Debug, Serialize, Deserialize, Clone, PartialEq, Eq)]
+#[derive(Debug)]
 pub struct SerdeAccountsLtHash(
     // serde only has array support up to 32 elements; anything larger needs to be handled manually
     // see https://github.com/serde-rs/serde/issues/1937 for more information
-    #[serde_as(as = "[_; 1024]")] pub [u16; 1024],
+    pub [u16; 1024],
 );
+
+impl<'de> Deserialize<'de> for SerdeAccountsLtHash {
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    where
+        D: Deserializer<'de>,
+    {
+        struct ArrayVisitor {
+            element: PhantomData<u16>,
+        }
+        impl<'de> de::Visitor<'de> for ArrayVisitor {
+            type Value = [u16; 1024];
+            fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
+                formatter.write_str(concat!("a u16 array of length 1024"))
+            }
+            fn visit_seq<A>(self, mut seq: A) -> Result<Self::Value, A::Error>
+            where
+                A: de::SeqAccess<'de>,
+            {
+                let mut arr = [0u16; 1024];
+                for (i, elem) in arr.iter_mut().enumerate() {
+                    *elem = seq
+                        .next_element()?
+                        .ok_or_else(|| de::Error::invalid_length(i, &self))?;
+                }
+                Ok(arr)
+            }
+        }
+
+        let visitor = ArrayVisitor {
+            element: PhantomData,
+        };
+        let array = deserializer.deserialize_tuple(1024, visitor)?;
+        Ok(Self(array))
+    }
+}