Fix SpecsAreNotPlugins error for wheel-based and rattler-built packages

PackageInfo.from_record() relied on conda's deprecated info/files
manifest to discover .dist-info directories. Packages built by
rattler-build (e.g. numpy) don't ship info/files at all, and
wheel packages extracted by conda-pypi have neither info/files
nor info/paths.json.

Read info/paths.json first (the canonical source per the conda
package contents CEP), fall back to info/files for older packages,
and scan the filesystem as a last resort for bare wheels.

Fixes #105

Author: jezdez

conda_self/package_info.py

@@ -1,6 +1,7 @@
 from __future__ import annotations
 
 import configparser
+import json
 import os
 import sys
 from pathlib import Path
@@ -20,6 +21,25 @@ class CaseSensitiveConfigParser(configparser.ConfigParser):
     optionxform = staticmethod(str)  # type: ignore
 
 
+def _file_paths_from_extracted_package(pkg_dir: str) -> list[str]:
+    """Read file paths from an extracted package directory.
+
+    Tries info/paths.json first (canonical per CEP), then falls back
+    to info/files (deprecated legacy format).
+    """
+    pkg_path = Path(pkg_dir)
+
+    paths_json = pkg_path / "info/paths.json"
+    if paths_json.is_file():
+        data = json.loads(paths_json.read_text())
+        return [entry["_path"] for entry in data.get("paths", [])]
+
+    try:
+        return (pkg_path / "info/files").read_text().splitlines()
+    except FileNotFoundError:
+        return []
+
+
 class PackageInfo:
     def __init__(self, dist_info_path: Path):
         """Describe the dist-info for a Python package installed as a conda package"""
@@ -29,16 +49,10 @@ def __init__(self, dist_info_path: Path):
     def from_record(
         cls, record: PrefixRecord | PackageCacheRecord
     ) -> list[PackageInfo]:
+        had_manifest = True
         if not (paths := getattr(record, "files", None)):
-            try:
-                paths = (
-                    Path(record.extracted_package_dir, "info/files")
-                    .read_text()
-                    .splitlines()
-                )
-            except FileNotFoundError:
-                # missing info/files -> empty package
-                paths = []
+            paths = _file_paths_from_extracted_package(record.extracted_package_dir)
+            had_manifest = bool(paths)
         dist_infos = set()
         for path in paths:
             if (maybe_dist_info := os.path.dirname(path)).endswith(".dist-info"):
@@ -47,6 +61,15 @@ def from_record(
             basedir = sys.prefix
         else:
             basedir = record.extracted_package_dir
+
+        if not dist_infos and not had_manifest:
+            # Last resort: scan the extracted directory for .dist-info
+            # directories directly (e.g. bare wheel with no conda metadata).
+            basepath = Path(basedir)
+            for candidate in basepath.rglob("*.dist-info"):
+                if candidate.is_dir():
+                    dist_infos.add(str(candidate.relative_to(basepath)))
+
         if not dist_infos:
             raise NoDistInfoDirFound(record.name, basedir)
         return [cls(Path(basedir, p)) for p in dist_infos]

tests/test_package_info.py

@@ -0,0 +1,179 @@
+from __future__ import annotations
+
+import json
+from dataclasses import dataclass, field
+
+import pytest
+
+from conda_self.exceptions import NoDistInfoDirFound
+from conda_self.package_info import PackageInfo
+
+
+@dataclass
+class FakeCacheRecord:
+    name: str
+    extracted_package_dir: str
+    files: list[str] | None = field(default=None)
+
+
+@pytest.fixture()
+def cache_record(tmp_path):
+    def _make(files=None):
+        return FakeCacheRecord(
+            name="some-plugin",
+            extracted_package_dir=str(tmp_path),
+            files=files,
+        )
+
+    return _make
+
+
+def test_finds_dist_info_via_info_files(tmp_path, cache_record):
+    dist_info = tmp_path / "lib/python3.12/site-packages/pkg-1.0.dist-info"
+    dist_info.mkdir(parents=True)
+    (dist_info / "entry_points.txt").write_text("[conda]\nplugin = pkg.plugin\n")
+
+    info_dir = tmp_path / "info"
+    info_dir.mkdir()
+    (info_dir / "files").write_text(
+        "lib/python3.12/site-packages/pkg-1.0.dist-info/entry_points.txt\n"
+        "lib/python3.12/site-packages/pkg/__init__.py\n"
+    )
+
+    infos = PackageInfo.from_record(cache_record())
+
+    assert len(infos) == 1
+    assert infos[0].dist_info_path == dist_info
+    assert "conda" in infos[0].entry_points()
+
+
+def test_finds_dist_info_via_paths_json(tmp_path, cache_record):
+    dist_info = tmp_path / "site-packages/pkg-1.0.dist-info"
+    dist_info.mkdir(parents=True)
+    (dist_info / "entry_points.txt").write_text("[conda]\nplugin = pkg.plugin\n")
+
+    info_dir = tmp_path / "info"
+    info_dir.mkdir()
+    (info_dir / "paths.json").write_text(
+        json.dumps(
+            {
+                "paths_version": 1,
+                "paths": [
+                    {
+                        "_path": "site-packages/pkg-1.0.dist-info/entry_points.txt",
+                        "path_type": "hardlink",
+                        "sha256": "abc123",
+                        "size_in_bytes": 39,
+                    },
+                    {
+                        "_path": "site-packages/pkg/__init__.py",
+                        "path_type": "hardlink",
+                        "sha256": "def456",
+                        "size_in_bytes": 100,
+                    },
+                ],
+            }
+        )
+    )
+
+    infos = PackageInfo.from_record(cache_record())
+
+    assert len(infos) == 1
+    assert infos[0].dist_info_path == dist_info
+    assert "conda" in infos[0].entry_points()
+
+
+def test_paths_json_takes_precedence_over_info_files(tmp_path, cache_record):
+    """info/paths.json is the canonical source per the conda package CEP."""
+    dist_info = tmp_path / "site-packages/real-1.0.dist-info"
+    dist_info.mkdir(parents=True)
+    (dist_info / "entry_points.txt").write_text("[conda]\nplugin = real.p\n")
+
+    info_dir = tmp_path / "info"
+    info_dir.mkdir()
+
+    # paths.json points to the real dist-info
+    (info_dir / "paths.json").write_text(
+        json.dumps(
+            {
+                "paths_version": 1,
+                "paths": [
+                    {
+                        "_path": "site-packages/real-1.0.dist-info/entry_points.txt",
+                        "path_type": "hardlink",
+                        "sha256": "abc",
+                        "size_in_bytes": 1,
+                    },
+                ],
+            }
+        )
+    )
+
+    # info/files points to a stale/wrong dist-info
+    (info_dir / "files").write_text(
+        "site-packages/stale-1.0.dist-info/entry_points.txt\n"
+    )
+
+    infos = PackageInfo.from_record(cache_record())
+
+    assert len(infos) == 1
+    assert infos[0].dist_info_path == dist_info
+
+
+@pytest.mark.parametrize(
+    "dist_info_relpath",
+    [
+        "pkg-1.0.dist-info",
+        "site-packages/pkg-1.0.dist-info",
+    ],
+)
+def test_filesystem_fallback_finds_dist_info(tmp_path, cache_record, dist_info_relpath):
+    dist_info = tmp_path / dist_info_relpath
+    dist_info.mkdir(parents=True)
+    (dist_info / "entry_points.txt").write_text("[conda]\nplugin = pkg.plugin\n")
+
+    infos = PackageInfo.from_record(cache_record())
+
+    assert len(infos) == 1
+    assert infos[0].dist_info_path == dist_info
+    assert "conda" in infos[0].entry_points()
+
+
+def test_no_dist_info_raises(tmp_path, cache_record):
+    (tmp_path / "some_file.py").write_text("pass")
+
+    with pytest.raises(NoDistInfoDirFound):
+        PackageInfo.from_record(cache_record())
+
+
+def test_no_fallback_when_manifest_exists(tmp_path, cache_record):
+    """rglob must not scan the filesystem when a file manifest was present."""
+    dist_info = tmp_path / "unrelated-1.0.dist-info"
+    dist_info.mkdir()
+    (dist_info / "entry_points.txt").write_text("[conda]\nplugin = x\n")
+
+    info_dir = tmp_path / "info"
+    info_dir.mkdir()
+    (info_dir / "files").write_text("lib/somefile.py\n")
+
+    with pytest.raises(NoDistInfoDirFound):
+        PackageInfo.from_record(cache_record())
+
+
+def test_entry_points_missing_file(tmp_path):
+    dist_info = tmp_path / "pkg-1.0.dist-info"
+    dist_info.mkdir()
+
+    assert PackageInfo(dist_info).entry_points() == {}
+
+
+def test_entry_points_non_conda(tmp_path):
+    dist_info = tmp_path / "pkg-1.0.dist-info"
+    dist_info.mkdir()
+    (dist_info / "entry_points.txt").write_text(
+        "[console_scripts]\npkg = pkg.cli:main\n"
+    )
+
+    ep = PackageInfo(dist_info).entry_points()
+    assert "conda" not in ep
+    assert "console_scripts" in ep