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17485cbcd2
Port from openai/codex#31494: user-visible history replay must strip CSI sequences and control characters. Stored conversation history can carry raw terminal escapes (pasted content, gateway-origin text, model output echoing injected tool results). Replaying it via /resume's recap panel or build_recap (/status on CLI + gateway) wrote those bytes straight to the terminal — an injected message could clear the screen, retitle the window, move the cursor, or restyle the recap UI. Rich's Text() does not neutralize raw escape bytes. - tools/ansi_strip.py: add sanitize_display_text() — strip_ansi() plus bare C0/C1 control removal, preserving \n and \t, normalizing \r to \n (adapted to Python from Codex's sanitize_user_text; reuses the existing ECMA-48 stripper instead of transcribing their char-walk) - hermes_cli/cli_agent_setup_mixin.py: sanitize user + assistant text in _display_resumed_history() before building the Rich recap panel - hermes_cli/session_recap.py: sanitize preview lines in build_recap() (_truncate choke point) so /status recaps are clean on every platform - tests: 10 new sanitize_display_text cases (incl. the exact codex#31494 fixture), recap + resume-display leak assertions
79 lines
3.4 KiB
Python
79 lines
3.4 KiB
Python
"""Strip ANSI escape sequences from subprocess output.
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Used by terminal_tool, code_execution_tool, and process_registry to clean
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command output before returning it to the model. This prevents ANSI codes
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from entering the model's context — which is the root cause of models
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copying escape sequences into file writes.
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Covers the full ECMA-48 spec: CSI (including private-mode ``?`` prefix,
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colon-separated params, intermediate bytes), OSC (BEL and ST terminators),
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DCS/SOS/PM/APC string sequences, nF multi-byte escapes, Fp/Fe/Fs
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single-byte escapes, and 8-bit C1 control characters.
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"""
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import re
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_ANSI_ESCAPE_RE = re.compile(
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r"\x1b"
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r"(?:"
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r"\[[\x30-\x3f]*[\x20-\x2f]*[\x40-\x7e]" # CSI sequence
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r"|\][\s\S]*?(?:\x07|\x1b\\)" # OSC (BEL or ST terminator)
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r"|[PX^_][\s\S]*?(?:\x1b\\)" # DCS/SOS/PM/APC strings
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r"|[\x20-\x2f]+[\x30-\x7e]" # nF escape sequences
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r"|[\x30-\x7e]" # Fp/Fe/Fs single-byte
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r")"
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r"|\x9b[\x30-\x3f]*[\x20-\x2f]*[\x40-\x7e]" # 8-bit CSI
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r"|\x9d[\s\S]*?(?:\x07|\x9c)" # 8-bit OSC
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r"|[\x80-\x9f]", # Other 8-bit C1 controls
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re.DOTALL,
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)
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# Fast-path check — skip full regex when no escape-like bytes are present.
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_HAS_ESCAPE = re.compile(r"[\x1b\x80-\x9f]")
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# C0 control characters (minus tab/newline/carriage-return, handled
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# separately) plus DEL. These survive strip_ansi() — it only removes
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# well-formed escape *sequences* — but are still dangerous or garbled
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# when echoed back to a terminal (BEL rings, backspace/DEL overwrite,
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# NUL truncates in some terminals).
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_CONTROL_CHARS_RE = re.compile(r"[\x00-\x08\x0b\x0c\x0e-\x1f\x7f]")
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# Fast-path check for sanitize_display_text — any C0 control (except
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# tab/newline), CR, DEL, ESC, or C1 byte triggers the slow path.
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_HAS_CONTROL = re.compile(r"[\x00-\x08\x0b-\x1f\x7f-\x9f]")
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def strip_ansi(text: str) -> str:
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"""Remove ANSI escape sequences from text.
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Returns the input unchanged (fast path) when no ESC or C1 bytes are
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present. Safe to call on any string — clean text passes through
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with negligible overhead.
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"""
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if not text or not _HAS_ESCAPE.search(text):
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return text
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return _ANSI_ESCAPE_RE.sub("", text)
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def sanitize_display_text(text: str) -> str:
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"""Sanitize stored/untrusted text before echoing it to a terminal.
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Removes ANSI/ECMA-48 escape sequences AND bare control characters,
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preserving only newlines and tabs (carriage returns are normalized
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to newlines so ``\\r``-overwrite spoofing can't hide content).
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Use this when re-rendering conversation history or other persisted
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text in a terminal UI (e.g. the ``/resume`` recap): a message that
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arrived with embedded escapes — pasted content, gateway-origin
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text, or model output echoing injected tool results — must not be
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able to clear the screen, retitle the window, move the cursor, or
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restyle adjacent UI when replayed. Rich's ``Text()`` does NOT
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neutralize raw escape bytes, so sanitization has to happen before
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display. Mirrors openai/codex#31494 (``sanitize_user_text``).
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"""
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if not text or not _HAS_CONTROL.search(text):
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return text
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text = strip_ansi(text)
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if "\r" in text:
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text = text.replace("\r\n", "\n").replace("\r", "\n")
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return _CONTROL_CHARS_RE.sub("", text)
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