sdk: fix lut casing

Author: kcsongor

solana/scripts/regenerateIdl.ts

@@ -20,9 +20,17 @@ const idl: Idl = JSON.parse(fs.readFileSync(jsonPath, "utf8"));
 const name = titleCase(idl["name"]);
 
 idl.accounts?.forEach((account) => {
-  account.name = account.name.replace(/^[A-Z]+/, (match) =>
-    match.toLowerCase()
-  );
+  // NOTE: here we translate PascalCase to camelCase, with the exception of all
+  // uppercase account names, such as 'LUT', which we want to preserve.
+  //
+  // The translation needs to be done because anchor generates an invalid IDL file, so we patch it.
+  // Anchor handles all uppercase account names specially (when generating the account discriminator),
+  // so we need to preserve them.
+  if (!account.name.match(/^[A-Z]+$/)) {
+    account.name = account.name.replace(/^[A-Z]+/, (match) =>
+      match.toLowerCase()
+    );
+  }
 });
 
 // heredoc

solana/ts/idl/2_0_0/ts/example_native_token_transfers.ts

@@ -1246,7 +1246,7 @@ export type ExampleNativeTokenTransfers = {
       }
     },
     {
-      "name": "lut",
+      "name": "LUT",
       "type": {
         "kind": "struct",
         "fields": [
@@ -3178,7 +3178,7 @@ export const IDL: ExampleNativeTokenTransfers = {
       }
     },
     {
-      "name": "lut",
+      "name": "LUT",
       "type": {
         "kind": "struct",
         "fields": [

solana/ts/lib/ntt.ts

@@ -1048,6 +1048,10 @@ export namespace NTT {
     if (major < 2) return null;
 
     pdas = pdas ?? NTT.pdas(program.programId);
+    // @ts-ignore
+    // NOTE: lut is 'LUT' in the IDL, but 'lut' in the generated code
+    // It needs to be upper-cased in the IDL to compute the anchor
+    // account discriminator correctly
     const lut = await program.account.lut.fetchNullable(pdas.lutAccount());
     if (!lut) return null;