Command Log Classifier

Implement classify_command_log(events), a helper that summarizes shell commands from an agent run.

Requirements

• Each event is a dictionary with cmd, exit_code, and optional stdout / stderr (missing streams are empty).
• Return a dictionary with status, total, failed, first_failure_cmd, and redacted_logs.
• status is "passed" when no command failed, otherwise "failed".
• A command fails when exit_code != 0.
• Output on stderr doesn't make a zero-exit command fail; warnings still appear in redacted_logs.
• first_failure_cmd is the first failing command, or None.
• redacted_logs is a list of strings built from stdout then stderr for each event in order.
• Split each stream with newline rules equivalent to str.splitlines(); emit one entry per resulting line (including blank internal lines).
• Each entry uses the format "{stream}: {line}" (for example "stdout: one", "stderr: err [REDACTED]"). Empty or missing streams contribute no entries.
• Redact secret tokens matching the regex sk-[A-Za-z0-9_-]+ by replacing each match with [REDACTED] (token-level replace, not whole-line wipe).

Assume well-formed input: cmd is a string, exit_code is an integer, and present output streams are strings. Input validation isn't required. Empty input is passed with zero counts, no first failure, and no logs. Negative exit codes count as failures too.

The redaction rule applies only to stdout/stderr entries. first_failure_cmd is copied unchanged, and other secret formats remain unchanged. This exercise's narrow regex doesn't establish that arbitrary output is safe to publish. Matching is case-sensitive and can occur anywhere in a line; sk- alone doesn't match because the suffix needs at least one allowed character.

The supplied event order and stdout-before-stderr order define the result. Separate captured streams don't reveal their original chronological interleaving.

Example

events = [
    {"cmd": "pytest", "exit_code": 1, "stdout": "", "stderr": "failed"},
    {"cmd": "print", "exit_code": 0, "stdout": "sk-live", "stderr": "err sk-test_2"},
]
summary = classify_command_log(events)
assert summary["status"] == "failed"
assert summary["total"] == 2
assert summary["failed"] == 1
assert summary["first_failure_cmd"] == "pytest"
assert summary["redacted_logs"] == [
    "stderr: failed",
    "stdout: [REDACTED]",
    "stderr: err [REDACTED]",
]

Line separators are removed, internal blank lines remain, and a terminal separator doesn't create an extra trailing entry. For example, stdout "one\r\n\r\ntwo\n" produces "stdout: one", "stdout: ", "stdout: two". A stream containing just "\n" produces one blank entry; an empty stream produces none.

Constraints

• Preserve log line order.
• Leave inputs untouched.