IndexError: list index out of range during recursive validation on Windows

[nlebovits]

Description

When using Linter with recursive=True on Windows, validation of nested STAC structures (catalog → collection → item) raises an IndexError instead of returning validation results.

Minimal Reproducible Example

Create these three files:

catalog.json:

{
  "type": "Catalog",
  "stac_version": "1.0.0",
  "id": "test-catalog",
  "description": "Test",
  "links": [
    {"rel": "root", "href": "./catalog.json", "type": "application/json"},
    {"rel": "child", "href": "./collection.json", "type": "application/json"}
  ]
}

collection.json:

{
  "type": "Collection",
  "stac_version": "1.0.0",
  "id": "test-collection",
  "description": "Test",
  "license": "CC0-1.0",
  "extent": {
    "spatial": {"bbox": [[-180, -90, 180, 90]]},
    "temporal": {"interval": [["2020-01-01T00:00:00Z", null]]}
  },
  "links": [
    {"rel": "root", "href": "./catalog.json", "type": "application/json"},
    {"rel": "item", "href": "./item.json", "type": "application/geo+json"}
  ]
}

item.json:

{
  "type": "Feature",
  "stac_version": "1.0.0",
  "id": "test-item",
  "geometry": {"type": "Point", "coordinates": [0, 0]},
  "bbox": [-1, -1, 1, 1],
  "properties": {"datetime": "2020-06-15T12:00:00Z"},
  "links": [],
  "assets": {}
}

test.py:

from stac_check.lint import Linter

linter = Linter(item="catalog.json", recursive=True)
print("valid_stac:", linter.valid_stac)
print("validate_all:", linter.validate_all)

Expected Behavior

Validation results for all nested objects (catalog, collection, item).

Actual Behavior

On Windows, validate_all contains entries with:

'error_type': 'IndexError'
'error_message': 'list index out of range'

Environment

• stac-check version: 1.14.0
• Platform: Windows (tested on GitHub Actions windows-latest)
• Python: 3.10, 3.11, 3.12, 3.13

Notes

• Works correctly on Linux and macOS
• Non-recursive validation (recursive=False) works fine on Windows
• Likely related to path handling differences between Windows and Unix