From 2d89350ed56333b883482c674d8f9c47e8db3fab Mon Sep 17 00:00:00 2001
From: Ruben Verborgh <ruben@verborgh.org>
Date: Mon, 26 Apr 2021 15:08:39 +0100
Subject: [PATCH] fix: Improve identifier error messages.

---
 src/util/identifiers/BaseIdentifierStrategy.ts            | 4 ++--
 test/unit/util/identifiers/BaseIdentifierStrategy.test.ts | 4 ++--
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/util/identifiers/BaseIdentifierStrategy.ts b/src/util/identifiers/BaseIdentifierStrategy.ts
index d87e989f5..529a7fae4 100644
--- a/src/util/identifiers/BaseIdentifierStrategy.ts
+++ b/src/util/identifiers/BaseIdentifierStrategy.ts
@@ -13,10 +13,10 @@ export abstract class BaseIdentifierStrategy implements IdentifierStrategy {
 
   public getParentContainer(identifier: ResourceIdentifier): ResourceIdentifier {
     if (!this.supportsIdentifier(identifier)) {
-      throw new InternalServerError(`${identifier.path} is not supported`);
+      throw new InternalServerError(`The identifier ${identifier.path} is outside the configured identifier space.`);
     }
     if (this.isRootContainer(identifier)) {
-      throw new InternalServerError(`${identifier.path} is a root container and has no parent`);
+      throw new InternalServerError(`Cannot obtain the parent of ${identifier.path} because it is a root container.`);
     }
 
     // Trailing slash is necessary for URL library
diff --git a/test/unit/util/identifiers/BaseIdentifierStrategy.test.ts b/test/unit/util/identifiers/BaseIdentifierStrategy.test.ts
index 5e03c8905..5686bf39d 100644
--- a/test/unit/util/identifiers/BaseIdentifierStrategy.test.ts
+++ b/test/unit/util/identifiers/BaseIdentifierStrategy.test.ts
@@ -21,11 +21,11 @@ describe('A BaseIdentifierStrategy', (): void => {
 
   it('errors when attempting to get the parent of an unsupported identifier.', async(): Promise<void> => {
     expect((): any => strategy.getParentContainer({ path: '/unsupported' }))
-      .toThrow('/unsupported is not supported');
+      .toThrow('The identifier /unsupported is outside the configured identifier space.');
   });
 
   it('errors when attempting to get the parent of a root container.', async(): Promise<void> => {
     expect((): any => strategy.getParentContainer({ path: 'http://test.com/root' }))
-      .toThrow('http://test.com/root is a root container and has no parent');
+      .toThrow('Cannot obtain the parent of http://test.com/root because it is a root container.');
   });
 });