refactor testing

test/helpers/env.js

@@ -0,0 +1,54 @@
+/**
+ * Functional helpers for test environment management.
+ * Returns new objects instead of mutating process.env directly.
+ */
+
+/**
+ * Creates a new env object with specified overrides
+ * @param {Record<string, string | undefined>} overrides - Env vars to set/override
+ * @returns {Record<string, string>} New env object
+ */
+export const withEnv = overrides => ({
+  ...process.env,
+  ...Object.fromEntries(
+    Object.entries(overrides).filter(([, v]) => v !== undefined),
+  ),
+})
+
+/**
+ * Creates a new env object with specified vars removed
+ * @param {string[]} keys - Env var keys to remove
+ * @returns {Record<string, string>} New env object
+ */
+export const withoutEnv = (keys) => {
+  const result = { ...process.env }
+  for (const key of keys) {
+    delete result[key]
+  }
+  return result
+}
+
+/**
+ * Executes a function with a temporary env, restoring original after
+ * @param {Record<string, string | undefined>} env - Temporary env to use
+ * @param {() => any} fn - Function to execute
+ * @returns {any} Result of fn()
+ */
+export const withTemporaryEnv = (env, fn) => {
+  const original = { ...process.env }
+  try {
+    // Set defined values
+    Object.entries(env).forEach(([key, value]) => {
+      if (value !== undefined) {
+        process.env[key] = value
+      }
+      else {
+        delete process.env[key]
+      }
+    })
+    return fn()
+  }
+  finally {
+    process.env = original
+  }
+}