feat: add joinURL

app/javascript/shared/helpers/joinUrl.js

@@ -0,0 +1,30 @@
+/**
+ * Join multiple paths together with a base URL
+ * NOTE: This function is not designed to handle query strings or fragments
+ *
+ * @param {string} baseUrl - The base URL to join the paths to
+ * @param  {...string} paths - The paths to join
+ * @returns {string} - The full URL
+ */
+export function joinUrl(baseUrl, ...paths) {
+  // remove empty undefined and null path items
+  // also handle if the path is just a slash or just multiple slashes only
+  const sanitizedPaths = paths.filter(path => {
+    if (!path) return false;
+    if (path === null && path === '') return false;
+    // if path is just a sequence of slashes
+    if (/^\/+$/.test(path)) return false;
+
+    return true;
+  });
+
+  const fullUrl = sanitizedPaths.reduce(
+    (acc, path) => {
+      const sanitizedPath = path.replace(/^\/+|\/+$/g, ''); // Remove leading and trailing slashes from each path segment
+      return `${acc}/${sanitizedPath}`; // Concatenate with a single slash
+    },
+    baseUrl.replace(/\/+$/, '')
+  );
+
+  return fullUrl;
+}

app/javascript/shared/helpers/specs/joinUrl.spec.js

@@ -0,0 +1,59 @@
+import { joinUrl } from '../joinUrl';
+
+describe('joinUrl', () => {
+  it('should correctly join base URL and multiple paths', () => {
+    expect(joinUrl('http://example.com', 'path1', 'path2', 'path3')).toBe(
+      'http://example.com/path1/path2/path3'
+    );
+  });
+
+  it('should handle trailing slashes on the base URL', () => {
+    expect(joinUrl('http://example.com/', 'path1', 'path2')).toBe(
+      'http://example.com/path1/path2'
+    );
+  });
+
+  it('should handle leading and trailing slashes on path segments', () => {
+    expect(joinUrl('http://example.com', '/path1/', '/path2/')).toBe(
+      'http://example.com/path1/path2'
+    );
+  });
+
+  it('should handle a mix of slashes in base URL and paths', () => {
+    expect(joinUrl('http://example.com/', '/path1/', '/path2/')).toBe(
+      'http://example.com/path1/path2'
+    );
+  });
+
+  it('should return the base URL if no paths are provided', () => {
+    expect(joinUrl('http://example.com')).toBe('http://example.com');
+  });
+
+  it('should handle empty path segments', () => {
+    expect(joinUrl('http://example.com', '', 'path1', '', 'path2')).toBe(
+      'http://example.com/path1/path2'
+    );
+  });
+
+  it('should handle paths that are just slashes', () => {
+    expect(joinUrl('http://example.com', '/', '//', '/path1/', '/')).toBe(
+      'http://example.com/path1'
+    );
+  });
+
+  it('should handle null and undefined paths', () => {
+    expect(
+      joinUrl('http://example.com', null, 'path1', undefined, 'path2')
+    ).toBe('http://example.com/path1/path2');
+  });
+
+  it('should handle paths with multiple consecutive slashes', () => {
+    expect(joinUrl('http://example.com', '///path1///', 'path2///')).toBe(
+      'http://example.com/path1/path2'
+    );
+  });
+
+  it('should handle only slashes in base URL and paths', () => {
+    expect(joinUrl('http://example.com/', '/', '/')).toBe('http://example.com');
+  });
+});