errors tests

Author: mdjastrzebski

src/helpers/__tests__/errors.test.ts

@@ -0,0 +1,80 @@
+import { ErrorWithStack, copyStackTrace } from '../errors';
+
+describe('ErrorWithStack', () => {
+  test('should create an error with message and handle stack trace capture', () => {
+    const error = new ErrorWithStack('Test error', ErrorWithStack);
+    expect(error.message).toBe('Test error');
+    expect(error).toBeInstanceOf(Error);
+  });
+
+  test('should capture stack trace if Error.captureStackTrace is available', () => {
+    const originalCaptureStackTrace = Error.captureStackTrace;
+    const captureStackTraceSpy = jest.fn();
+    Error.captureStackTrace = captureStackTraceSpy;
+
+    const error = new ErrorWithStack('Test error', ErrorWithStack);
+    expect(captureStackTraceSpy).toHaveBeenCalledWith(error, ErrorWithStack);
+
+    Error.captureStackTrace = originalCaptureStackTrace;
+  });
+
+  test('should work when Error.captureStackTrace is not available', () => {
+    const originalCaptureStackTrace = Error.captureStackTrace;
+    // @ts-expect-error - intentionally removing captureStackTrace
+    delete Error.captureStackTrace;
+
+    const error = new ErrorWithStack('Test error', ErrorWithStack);
+    expect(error.message).toBe('Test error');
+    expect(error).toBeInstanceOf(Error);
+
+    Error.captureStackTrace = originalCaptureStackTrace;
+  });
+});
+
+describe('copyStackTrace', () => {
+  test('should copy stack trace from source to target when both are Error instances', () => {
+    const target = new Error('Target error');
+    const source = new Error('Source error');
+    source.stack = 'Error: Source error\n    at test.js:1:1';
+
+    copyStackTrace(target, source);
+
+    expect(target.stack).toBe('Error: Target error\n    at test.js:1:1');
+  });
+
+  test('should handle stack trace with multiple occurrences of source message', () => {
+    const target = new Error('Target error');
+    const source = new Error('Source error');
+    source.stack =
+      'Error: Source error\n    at test.js:1:1\nError: Source error\n    at test.js:2:2';
+
+    copyStackTrace(target, source);
+
+    // Should replace only the first occurrence
+    expect(target.stack).toBe(
+      'Error: Target error\n    at test.js:1:1\nError: Source error\n    at test.js:2:2',
+    );
+  });
+
+  test('should not modify target when conditions are not met', () => {
+    const targetNotError = { message: 'Not an error' };
+    const source = new Error('Source error');
+    source.stack = 'Error: Source error\n    at test.js:1:1';
+
+    copyStackTrace(targetNotError, source);
+    expect(targetNotError).toEqual({ message: 'Not an error' });
+
+    const target = new Error('Target error');
+    const originalStack = target.stack;
+    const sourceNotError = { message: 'Not an error' };
+
+    copyStackTrace(target, sourceNotError as Error);
+    expect(target.stack).toBe(originalStack);
+
+    const sourceNoStack = new Error('Source error');
+    delete sourceNoStack.stack;
+
+    copyStackTrace(target, sourceNoStack);
+    expect(target.stack).toBe(originalStack);
+  });
+});

src/helpers/errors.ts

@@ -1,5 +1,3 @@
-import prettyFormat from 'pretty-format';
-
 export class ErrorWithStack extends Error {
   // eslint-disable-next-line @typescript-eslint/no-unsafe-function-type
   constructor(message: string | undefined, callsite: Function) {
@@ -10,44 +8,6 @@ export class ErrorWithStack extends Error {
   }
 }
 
-export const prepareErrorMessage = (
-  // TS states that error caught in a catch close are of type `unknown`
-  // most real cases will be `Error`, but better safe than sorry
-  error: unknown,
-  name?: string,
-  value?: unknown,
-): string => {
-  let errorMessage: string;
-  if (error instanceof Error) {
-    // Strip info about custom predicate
-    errorMessage = error.message.replace(/ matching custom predicate[^]*/gm, '');
-  } else if (error && typeof error === 'object') {
-    errorMessage = error.toString();
-  } else {
-    errorMessage = 'Caught unknown error';
-  }
-
-  if (name && value) {
-    errorMessage += ` with ${name} ${prettyFormat(value, { min: true })}`;
-  }
-  return errorMessage;
-};
-
-// eslint-disable-next-line @typescript-eslint/no-unsafe-function-type
-export const createQueryByError = (error: unknown, callsite: Function): null => {
-  if (error instanceof Error) {
-    if (error.message.includes('No instances found')) {
-      return null;
-    }
-    throw new ErrorWithStack(error.message, callsite);
-  }
-
-  throw new ErrorWithStack(
-    `Query: caught unknown error type: ${typeof error}, value: ${error}`,
-    callsite,
-  );
-};
-
 export function copyStackTrace(target: unknown, stackTraceSource: Error) {
   if (target instanceof Error && stackTraceSource.stack) {
     target.stack = stackTraceSource.stack.replace(stackTraceSource.message, target.message);