Could it be because I am generating the warnings by printing directly to STDERR

Yes:

use strict;
use warnings;

use Test::More tests => 2;
use Test::Warn;

# Your code which gives an expected warning
sub foo {
    warn "Stripe Webhook Error: Invalid Stripe Signature\n";
}

sub bar {
    STDERR->print ("Stripe Webhook Error: Invalid Stripe Signature\n")
+;
}

# Test your code
warning_is { foo (); } "Stripe Webhook Error: Invalid Stripe Signature
+\n",
    'Invalid sig warning issued';
warning_is { bar (); } "Stripe Webhook Error: Invalid Stripe Signature
+\n",
    'Invalid sig STDERR print issued';

[download]

So don't do that. :-)

🦛

In reply to Re^5: STDERR in Test Results by hippo
in thread STDERR in Test Results by Bod

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