feat(core): add metadatum parsing utils

Cardano.util.asMetadatumMap and Cardano.util.asMetadatumArray

packages/core/src/Cardano/types/Asset.ts

@@ -107,6 +107,9 @@ export interface Asset {
   name: string;
   fingerprint: AssetFingerprint;
   quantity: bigint;
+  /**
+   * Sorted by slot
+   */
   history: AssetMintOrBurn[];
   metadata?: AssetMetadata;
 }

packages/core/src/Cardano/types/AuxiliaryData.ts

@@ -6,7 +6,7 @@
 // } else if (Array.isArray(metadatum)) {
 // } else if (metadatum instanceof Uint8Array) {
 // } else {
-//   // a is MetadatumMap
+//   // metadatum is MetadatumMap
 // }
 
 import * as Cardano from '.';

packages/core/src/Cardano/util/index.ts

@@ -1,3 +1,4 @@
 export * from './coalesceValueQuantities';
 export * from './computeMinUtxoValue';
 export * from './primitives';
+export * as metadatum from './metadatum';

packages/core/src/Cardano/util/metadatum.ts

@@ -0,0 +1,21 @@
+import { Metadatum, MetadatumMap } from '../types';
+
+/**
+ * @returns {MetadatumMap | null} null if Metadatum is not MetadatumMap
+ */
+export const asMetadatumMap = (metadatum: Metadatum): MetadatumMap | null => {
+  if (typeof metadatum === 'object' && !Array.isArray(metadatum) && !(metadatum instanceof Uint8Array)) {
+    return metadatum;
+  }
+  return null;
+};
+
+/**
+ * @returns {Metadatum[] | null} null if Metadatum is not an array of metadatum
+ */
+export const asMetadatumArray = (metadatum: Metadatum): Metadatum[] | null => {
+  if (Array.isArray(metadatum)) {
+    return metadatum;
+  }
+  return null;
+};

packages/core/test/Cardano/util/metadatum.test.ts

@@ -0,0 +1,27 @@
+import { Cardano } from '@cardano-sdk/core';
+
+describe('Cardano.util.metadatum', () => {
+  describe('asMetadatumMap', () => {
+    it('returns argument if it is a MetadatumMap', () => {
+      const metadatum: Cardano.Metadatum = { some: 'metadatum' };
+      expect(Cardano.util.metadatum.asMetadatumMap(metadatum)).toBe(metadatum);
+    });
+
+    it('returns null for any other metadatum type', () => {
+      const metadatum: Cardano.Metadatum = [{ some: 'metadatum' }];
+      expect(Cardano.util.metadatum.asMetadatumMap(metadatum)).toBeNull();
+    });
+  });
+
+  describe('asMetadatumArray', () => {
+    it('returns argument if it is Metadatum[]', () => {
+      const metadatum: Cardano.Metadatum = [{ some: 'metadatum' }];
+      expect(Cardano.util.metadatum.asMetadatumArray(metadatum)).toBe(metadatum);
+    });
+
+    it('returns null for any other metadatum type', () => {
+      const metadatum: Cardano.Metadatum = { some: 'metadatum' };
+      expect(Cardano.util.metadatum.asMetadatumArray(metadatum)).toBeNull();
+    });
+  });
+});