Smarter parsing of aliases in frontmatter

src/search.ts

@@ -2,6 +2,7 @@ import { App, getAllTags, TFile, CachedMetadata } from 'obsidian';
 import { findAll } from 'highlight-words-core';
 
 import { PageIndex, SearchIndex, TagIndex, AliasIndex } from './searchTypings';
+import { getAliases } from './utils/getAliases';
 
 type SearchResult = {
   start: number;
@@ -66,7 +67,7 @@ export default class Search {
     cache.forEach((fileCache) => {
       this.searchIndex.push(new PageIndex(fileCache.file));
 
-      fileCache.metadata.frontmatter?.aliases?.forEach((alias: string) => {
+      getAliases(fileCache.metadata).forEach((alias: string) => {
         this.searchIndex.push(new AliasIndex(alias, fileCache.file));
       });
     });

src/utils/getAliases.spec.ts

@@ -0,0 +1,42 @@
+import { CachedMetadata, FrontMatterCache } from 'obsidian';
+
+import { getAliases } from './getAliases';
+
+describe('getAliases', () => {
+  it('Returns an empty array if no frontmatter is defined', () => {
+    const metadata: CachedMetadata = {};
+    const aliases = getAliases(metadata);
+    expect(aliases).toEqual([]);
+  });
+
+  it('Returns an empty array if no aliases are defined', () => {
+    const metadata: CachedMetadata = {
+      frontmatter: {} as FrontMatterCache,
+    };
+
+    const aliases = getAliases(metadata);
+    expect(aliases).toEqual([]);
+  });
+
+  it('Parses aliases defined as a string split by comma', () => {
+    const metadata: CachedMetadata = {
+      frontmatter: {
+        aliases: 'foo, bar ',
+      } as unknown as FrontMatterCache,
+    };
+
+    const aliases = getAliases(metadata);
+    expect(aliases).toEqual(['foo', 'bar']);
+  });
+
+  it('Parses aliases defined as an array of values', () => {
+    const metadata: CachedMetadata = {
+      frontmatter: {
+        aliases: ['foo', 'bar'],
+      } as unknown as FrontMatterCache,
+    };
+
+    const aliases = getAliases(metadata);
+    expect(aliases).toEqual(['foo', 'bar']);
+  });
+});

src/utils/getAliases.ts

@@ -0,0 +1,13 @@
+import { CachedMetadata } from 'obsidian';
+
+export const getAliases = (metadata: CachedMetadata): string[] => {
+  const frontmatterAliases = metadata?.frontmatter?.['aliases'];
+
+  if (typeof frontmatterAliases === 'string') {
+    return frontmatterAliases.split(',').map((alias: string) => alias.trim());
+  } else if (Array.isArray(frontmatterAliases)) {
+    return frontmatterAliases as string[];
+  }
+
+  return [];
+};