feat(templates): add decodeURIComponent helper (#19616)

docs/usage/templates.md

@@ -49,6 +49,16 @@ In the example above `baseDir` is the string you want to transform into a valid
 
 Read the [MDN Web Docs, encodeURIComponent()](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/encodeURIComponent) to learn more.
 
+### decodeURIComponent
+
+If you want to decode a percent-encoded string, use the built-in function `decodeURIComponent` like this:
+
+`{{{decodeURIComponent depName}}}`
+
+In the example above `depName` is the string you want to decode.
+
+Read the [MDN Web Docs, decodeURIComponent()](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/decodeURIComponent) to learn more.
+
 ### replace
 
 The `replace` helper replaces _all_ found strings with the replacement string.

lib/util/template/index.spec.ts

@@ -158,4 +158,22 @@ describe('util/template/index', () => {
       expect(template.containsTemplates('{{body}}', ['logJSON'])).toBeFalse();
     });
   });
+
+  describe('percent encoding', () => {
+    it('encodes values', () => {
+      const output = template.compile(
+        '{{{encodeURIComponent "@fsouza/prettierd"}}}',
+        undefined as never
+      );
+      expect(output).toBe('%40fsouza%2Fprettierd');
+    });
+
+    it('decodes values', () => {
+      const output = template.compile(
+        '{{{decodeURIComponent "%40fsouza/prettierd"}}}',
+        undefined as never
+      );
+      expect(output).toBe('@fsouza/prettierd');
+    });
+  });
 });

lib/util/template/index.ts

@@ -4,6 +4,7 @@ import { GlobalConfig } from '../../config/global';
 import { logger } from '../../logger';
 
 handlebars.registerHelper('encodeURIComponent', encodeURIComponent);
+handlebars.registerHelper('decodeURIComponent', decodeURIComponent);
 
 handlebars.registerHelper('stringToPrettyJSON', (input: string): string =>
   JSON.stringify(JSON.parse(input), null, 2)