Operator: Fix error output and prevent silent failures in next command

[matta]

Addresses two key UX issues:

1. pebble next --json returned {"tasks":[]} and exited with code 0 when no tasks were found. This violated the rule to consistently use exit code > 0 for missing items to prevent silent failures in automated scripts.
2. The default error handler in main.rs used the Debug formatter ({:?}), which dumped noisy stack traces with ANSI color escapes directly to stderr. This made error parsing difficult and intimidating. It has been replaced with the standard Display formatter ({}) prefixed with error: .

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PR created automatically by Jules for task 7910046922314857452 started by @matta

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Summary of Changes

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This pull request enhances the user experience and reliability of the pebble CLI tool by addressing two critical issues related to error handling and command output. It standardizes error messages for better readability and machine parsing, and corrects the exit code behavior of the next command when no results are found, ensuring that automation scripts can reliably detect and react to the absence of tasks.

Highlights

• Improved Error Output: The application's error messages printed to stderr have been standardized. Previously, verbose Debug formatter output with stack traces and ANSI color escapes was used, making errors difficult to parse. Now, all errors use the Display formatter ({}) and are prefixed with error: for cleaner, more consistent output.
• Corrected pebble next --json Exit Code: The pebble next --json command previously returned an exit code of 0 and an empty JSON array ({"tasks":[]}) when no tasks were found. This behavior has been corrected to return a non-zero exit code (specifically, an NotFoundError) in such cases, aligning with standard CLI practices for indicating missing items and preventing silent failures in automated scripts.

Changelog

• .jules/operator.md
  • Documented the new standard for error output using Display formatting and error: prefix.
  • Documented the standard for NotFoundError to be returned before checking --json for retrieval commands.
• crates/pebble/src/commands.rs
  • Moved the tasks.is_empty() check in run_next to occur before the ctx.json block.
  • Ensured that NotFoundError is returned when no tasks are found, even if --json is specified.
• crates/pebble/src/main.rs
  • Removed the import for NotFoundError as it's no longer handled separately in main.
  • Unified error output in main to use eprintln!("error: {}", err); for all error types, including UsageError and general runtime errors.
  • Removed the specific eprintln!("Runtime error: {:?}", err); which used Debug formatting.
• crates/pebble/tests/integration/cli_check.rs
  • Updated assert_issue_stderr to check for "error:" instead of "Runtime error:" in stderr.
  • Updated test_check_modes_issue_json_payload_is_identical to check for "error:" instead of "Runtime error:" in stderr.
• crates/pebble/tests/integration/cli_json.rs
  • Added write_task to test_next_json_stdout_only to ensure a task exists for the test.
  • Updated the assertion in test_next_json_stdout_only to expect 1 task instead of 0.

Activity

• PR created automatically by Jules for task 7910046922314857452 started by @matta.

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Code Review

This pull request standardizes error output and exit codes across the pebble CLI. It updates the operator.md documentation to reflect new guidelines for error formatting and non-zero exit codes for search commands that find no results. Specifically, the run_next command now returns a NotFoundError with a non-zero exit code if no tasks are found, even when --json is used, addressing a silent failure anti-pattern. Error handling in main.rs is refactored to consistently print error: <message> to stderr, removing verbose debug output. Corresponding integration tests have been updated to assert against the new standardized error messages and the expected JSON output for the next command.