Add util function and related tests

Signed-off-by: Brian Hudson <brian.r.hudson@gmail.com>

packages/repo-tools/src/commands/generate-catalog-info/generate-catalog-info.ts

@@ -33,6 +33,7 @@ import {
   isFulfilled,
   readFile,
   writeFile,
+  safeEntityName,
 } from './utils';
 import { CodeOwnersEntry } from 'codeowners-utils';
 
@@ -164,18 +165,7 @@ async function fixCatalogInfoYaml(options: FixOptions) {
     codeowners,
     relativePath('.', yamlPath),
   );
-  const safeName = packageJson.name
-    .replace(/^[^\w\s]|[^a-z0-9]$/g, '')
-    .replace(/[^A-Za-z0-9_\-.]+/g, '-')
-    .replace(/([A-Z])/g, (_, letter, index, original) => {
-      if (index !== 0) {
-        const previousChar = original[index - 1];
-        if (previousChar !== '-') {
-          return `-${letter.toLowerCase()}`;
-        }
-      }
-      return letter.toLowerCase();
-    });
+  const safeName = safeEntityName(packageJson.name);
   let yamlJson: BackstagePackageEntity;
 
   try {
@@ -249,18 +239,7 @@ function createOrMergeEntity(
   owner: string,
   existingEntity: BackstagePackageEntity | Record<string, any> = {},
 ): BackstagePackageEntity {
-  const safeEntityName = packageJson.name
-    .replace(/^[^\w\s]|[^a-z0-9]$/g, '')
-    .replace(/[^A-Za-z0-9_\-.]+/g, '-')
-    .replace(/([A-Z])/g, (_, letter, index, original) => {
-      if (index !== 0) {
-        const previousChar = original[index - 1];
-        if (previousChar !== '-') {
-          return `-${letter.toLowerCase()}`;
-        }
-      }
-      return letter.toLowerCase();
-    });
+  const entityName = safeEntityName(packageJson.name);
 
   return {
     ...existingEntity,
@@ -269,7 +248,7 @@ function createOrMergeEntity(
     metadata: {
       ...existingEntity.metadata,
       // Provide default name/title/description values.
-      name: safeEntityName,
+      name: entityName,
       title: packageJson.name,
       ...(packageJson.description && !existingEntity.metadata?.description
         ? { description: packageJson.description }

packages/repo-tools/src/commands/generate-catalog-info/utils.test.ts

@@ -0,0 +1,36 @@
+/*
+ * Copyright 2024 The Backstage Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import { safeEntityName } from './utils';
+
+describe('utils', () => {
+  describe('safeEntityName', () => {
+    it('should remove non-alphanumeric characters at the start and end', () => {
+      const result = safeEntityName('%entityname$');
+      expect(result).toBe('entityname');
+    });
+
+    it('should replace non-alphanumeric characters, except - and _, with -', () => {
+      const result = safeEntityName('entity@#name$');
+      expect(result).toBe('entity-name');
+    });
+
+    it('should replace capital letters with - followed by the same letter in lowercase', () => {
+      const result = safeEntityName('EntityName');
+      expect(result).toBe('entity-name');
+    });
+  });
+});

packages/repo-tools/src/commands/generate-catalog-info/utils.ts

@@ -48,3 +48,20 @@ export const isRejected = (
 export const isFulfilled = <T>(
   input: PromiseSettledResult<T>,
 ): input is PromiseFulfilledResult<T> => input.status === 'fulfilled';
+
+/**
+ * Generates a suitable entity name from a package name by slugifying the given package name.
+ *
+ * @param packageName - The package name to generate an entity name from.
+ * @returns The generated entity name, a slugified version of the package name.
+ */
+export const safeEntityName = (packageName: string): string => {
+  return packageName
+    .replace(/^[^\w\s]|[^a-z0-9]$/g, '')
+    .replace(/[^A-Za-z0-9_\-.]+/g, '-')
+    .replace(
+      /([a-z])([A-Z])/g,
+      (_, a, b) => `${a}-${b.toLocaleLowerCase('en-US')}`,
+    )
+    .replace(/^(.)/, (_, a) => a.toLocaleLowerCase('en-US'));
+};