chore: migrate to typescript

web3.js/src/instruction.ts

@@ -0,0 +1,49 @@
+import {Buffer} from 'buffer';
+import * as BufferLayout from 'buffer-layout';
+
+import * as Layout from './layout';
+
+/**
+ * @typedef {Object} InstructionType
+ * @property (index} The Instruction index (from solana upstream program)
+ * @property (BufferLayout} The BufferLayout to use to build data
+ * @internal
+ */
+export type InstructionType = {
+  index: number;
+  layout: typeof BufferLayout;
+};
+
+/**
+ * Populate a buffer of instruction data using an InstructionType
+ * @internal
+ */
+export function encodeData(type: InstructionType, fields?: any): Buffer {
+  const allocLength =
+    type.layout.span >= 0 ? type.layout.span : Layout.getAlloc(type, fields);
+  const data = Buffer.alloc(allocLength);
+  const layoutFields = Object.assign({instruction: type.index}, fields);
+  type.layout.encode(layoutFields, data);
+  return data;
+}
+
+/**
+ * Decode instruction data buffer using an InstructionType
+ * @internal
+ */
+export function decodeData(type: InstructionType, buffer: Buffer): any {
+  let data;
+  try {
+    data = type.layout.decode(buffer);
+  } catch (err) {
+    throw new Error('invalid instruction; ' + err);
+  }
+
+  if (data.instruction !== type.index) {
+    throw new Error(
+      `invalid instruction; instruction index mismatch ${data.instruction} != ${type.index}`,
+    );
+  }
+
+  return data;
+}