Optionalcause: ErrorOptional ReadonlycauseSet when the config file is code that ran and threw - a fynpo.config.js. The user still
needs the stack to find the throw inside their own config, so the banner keeps it. A JSON
file has no code to blame and leaves this undefined, so its banner stays stack-free.
ReadonlycodeStable marker for isFynpoConfigError. instanceof is not reliable here: fyn and
fynpo each bundle their own copy of this module, so an error crossing between them is not
an instance of the local class.
Readonlyfilethe config file that failed to parse
Readonlyreasonthe underlying failure, without the Failed to ... framing
OptionalstackStaticstackThe Error.stackTraceLimit property specifies the number of stack frames
collected by a stack trace (whether generated by new Error().stack or
Error.captureStackTrace(obj)).
The default value is 10 but may be set to any valid JavaScript number. Changes
will affect any stack trace captured after the value has been changed.
If set to a non-number value, or set to a negative number, stack traces will not capture any frames.
StaticcaptureCreates a .stack property on targetObject, which when accessed returns
a string representing the location in the code at which
Error.captureStackTrace() was called.
const myObject = {};
Error.captureStackTrace(myObject);
myObject.stack; // Similar to `new Error().stack`
The first line of the trace will be prefixed with
${myObject.name}: ${myObject.message}.
The optional constructorOpt argument accepts a function. If given, all frames
above constructorOpt, including constructorOpt, will be omitted from the
generated stack trace.
The constructorOpt argument is useful for hiding implementation
details of error generation from the user. For instance:
function a() {
b();
}
function b() {
c();
}
function c() {
// Create an error without stack trace to avoid calculating the stack trace twice.
const { stackTraceLimit } = Error;
Error.stackTraceLimit = 0;
const error = new Error();
Error.stackTraceLimit = stackTraceLimit;
// Capture the stack trace above function b
Error.captureStackTrace(error, b); // Neither function c, nor b is included in the stack trace
throw error;
}
a();
OptionalconstructorOpt: FunctionStaticprepare
A config file that exists but can't be parsed is a user mistake, not a bug. FJM-189 made these surface instead of being swallowed - which was right, since a swallowed parse error got reported as "no config found" and let callers overwrite the broken file - but it left every CLI dumping a raw stack for a stray trailing comma.
The CLIs turn this into a plain warning and a clean exit, so the failure has to be distinguishable from every other way loading config can go wrong.