affaan-m/ECC · error · ContractError

has an invalid finite source duration

Error message

{label} has an invalid finite source duration

What it means

_validate_media_time requires the source_duration argument to be a finite, non-boolean real number before validating a media time value against it. The first check raises when source_duration is not a finite int/float (None, string, bool, NaN, inf). This ensures all later numeric comparisons are well-defined.

Solutions

1. Ensure the source JSON carries duration as a JSON number, not a string; convert with float() at authoring time.
2. Handle None/missing duration by fixing the upstream document before calling the validator.
3. Reject non-finite floats (NaN/Inf) when loading the document; they indicate corrupt probe data.
4. Sanitize bools out of numeric fields (isinstance(v, bool) check) before validation.

Example fix

// before
doc['duration'] = str(ffprobe_seconds)  # "12.5"
// after
doc['duration'] = float(ffprobe_seconds)  # 12.5

import math
def valid_source_duration(v) -> bool:
    return isinstance(v, (int, float)) and not isinstance(v, bool) and math.isfinite(v)

def is_finite_real(v) -> bool:
    return isinstance(v, (int, float)) and not isinstance(v, bool) and math.isfinite(v)

try:
    validate_genre_specs(spec, source_duration=dur)
except ContractError as e:
    if 'invalid finite source duration' in str(e):
        dur = float(probe['duration'])  # repair from probe
    else:
        raise

When it happens

Trigger: Calling any validator (validate_genre_specs, validate_effect_recipe, validate_provenance, validate_artifact_receipt, _validate_probe_evidence) with a source_duration of null, a numeric string like "12.5", True, NaN, or Infinity.

Common situations: Probe JSON where the duration field was omitted or left as a string, NaN/Infinity produced by upstream ffmpeg/ffprobe parsing, or bools slipping in from YAML's yes/no mapping to true/false.

Understand the failure class

Background: "Must be a positive integer", "Invalid value", "Unsupported": the invalid-argument-value error family, when a library rejects the value you pass — this error's family across 35 libraries.

Related errors

• Geometry, fps and duration must be finite and positive
• contains a non-finite numeric value
• is outside its source duration
• application bundle differs from its bound evidence
• At least one video is required

AI-assisted analysis of affaan-m/ECC@8321021c54 (2026-09-16). Data as JSON: /api/errors/b87cc6dc4e3b985c. Report an issue: GitHub.

Appendix: source

Thrown at skills/taste-application/scripts/tasteforge/contract.py:28

import stat
from pathlib import Path
from typing import Any, cast

_REQUIRED_MODALITIES = {"image", "video", "3d_asset"}
_SIGNATURE_AXES = {"materials", "motion", "composition", "avoid"}


class ContractError(ValueError):
    """The dry-run bundle is incomplete or has lost taste specificity."""


def _is_finite_real(value: Any) -> bool:
    return isinstance(value, (int, float)) and not isinstance(value, bool) and math.isfinite(value)


def _validate_media_time(value: Any, source_duration: Any, *, label: str) -> None:
    if not _is_finite_real(source_duration):
        raise ContractError(f"{label} has an invalid finite source duration")
    source_duration = cast(float, source_duration)
    if float(source_duration) <= 0:
        raise ContractError(f"{label} has an invalid finite source duration")
    if (not _is_finite_real(value) or float(value) < 0
            or float(value) > float(source_duration)):
        raise ContractError(f"{label} is outside its source duration")


def _validate_numeric_evidence(value: Any, *, label: str) -> None:
    if isinstance(value, bool):
        raise ContractError(f"{label} contains a boolean numeric value")
    if isinstance(value, (int, float)):
        if not math.isfinite(value):
            raise ContractError(f"{label} contains a non-finite numeric value")
    elif isinstance(value, dict):
        for nested in value.values():
            _validate_numeric_evidence(nested, label=label)
    elif isinstance(value, list):

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