From fb6618ed7efbad152eb31d905ab1c5fbcb6d033f Mon Sep 17 00:00:00 2001
From: "David W.H. Swenson" <david.swenson@omsf.io>
Date: Tue, 18 Mar 2025 16:28:24 -0500
Subject: [PATCH 01/15] Draft of GitHubReleaseSource

---
 src/spec0/releasesource.py | 94 ++++++++++++++++++++++++++++++++++++--
 1 file changed, 90 insertions(+), 4 deletions(-)

diff --git a/src/spec0/releasesource.py b/src/spec0/releasesource.py
index 028a090..34ba019 100644
--- a/src/spec0/releasesource.py
+++ b/src/spec0/releasesource.py
@@ -74,11 +74,97 @@ def _get_releases(self, package: str) -> Generator[Release, None, None]:
 
 
 class GitHubReleaseSource(ReleaseSource):
-    def _get_releases(self, package: str) -> Generator[Release, None, None]: ...
-
+    """Class to fetch all GitHub releases for a given repository using the GitHub GraphQL API."""
+
+    def __init__(self, github_token: str):
+        """
+        Initialize the release source with a GitHub token.
+
+        Parameters
+        ----------
+        github_token : str
+            Personal access token (PAT) with permissions to query the desired repository.
+        """
+        self.github_token = github_token
+
+    def _get_releases(self, owner_repo: str):
+        """
+        Generate all releases for a repository in descending order of creation date (most recent first).
+
+        Parameters
+        ----------
+        owner_repo : str
+            A string in the format "owner/repo" that identifies the repository.
+
+        Yields
+        ------
+        Release
+            A `Release` object containing:
+            - `version` (packaging.version.Version)
+            - `release_date` (datetime.datetime)
+
+        Warns
+        -----
+        UserWarning
+            When `tagName` from GitHub cannot be parsed as a valid version.
+        """
+        owner, repo = owner_repo.split("/", 1)
+
+        query = """
+        query($owner: String!, $repo: String!, $after: String) {
+          repository(owner: $owner, name: $repo) {
+            releases(first: 100, after: $after, orderBy: {field: CREATED_AT, direction: DESC}) {
+              pageInfo {
+                endCursor
+                hasNextPage
+              }
+              nodes {
+                tagName
+                createdAt
+              }
+            }
+          }
+        }
+        """
+
+        url = "https://api.github.com/graphql"
+        headers = {
+            "Authorization": f"Bearer {self.github_token}",
+            "Accept": "application/vnd.github.v3+json",
+        }
+
+        has_next_page = True
+        after_cursor = None
+
+        while has_next_page:
+            variables = {
+                "owner": owner,
+                "repo": repo,
+                "after": after_cursor,
+            }
+            response = requests.post(
+                url, json={"query": query, "variables": variables}, headers=headers
+            )
+            response.raise_for_status()
+
+            data = response.json()
+            releases_data = data["data"]["repository"]["releases"]
+
+            for node in releases_data["nodes"]:
+                tag_name = node["tagName"]
+                try:
+                    version = Version(tag_name)
+                except InvalidVersion:
+                    warnings.warn(f"Skipping invalid version: {tag_name}", UserWarning)
+                    continue  # Skip this release
+
+                release_date = datetime.fromisoformat(
+                    node["createdAt"].replace("Z", "+00:00")
+                )
+                yield Release(version, release_date)
 
-class GitHubTagReleaseSource(ReleaseSource):
-    def _get_releases(self, package: str) -> Generator[Release, None, None]: ...
+            has_next_page = releases_data["pageInfo"]["hasNextPage"]
+            after_cursor = releases_data["pageInfo"]["endCursor"]
 
 
 class CondaReleaseSource(ReleaseSource):

From daa8e9c84833fe7986fffd7c7086f91d59005900 Mon Sep 17 00:00:00 2001
From: "David W.H. Swenson" <david.swenson@omsf.io>
Date: Tue, 18 Mar 2025 16:56:24 -0500
Subject: [PATCH 02/15] Add tests for GitHubReleaseSource

---
 src/spec0/releasesource.py  |   5 +-
 tests/test_releasesource.py | 183 ++++++++++++++++++++++++++++++++++++
 2 files changed, 186 insertions(+), 2 deletions(-)

diff --git a/src/spec0/releasesource.py b/src/spec0/releasesource.py
index 34ba019..ad2df47 100644
--- a/src/spec0/releasesource.py
+++ b/src/spec0/releasesource.py
@@ -89,7 +89,8 @@ def __init__(self, github_token: str):
 
     def _get_releases(self, owner_repo: str):
         """
-        Generate all releases for a repository in descending order of creation date (most recent first).
+        Generate all releases for a repository in descending order of
+        creation date (most recent first).
 
         Parameters
         ----------
@@ -158,7 +159,7 @@ def _get_releases(self, owner_repo: str):
                     warnings.warn(f"Skipping invalid version: {tag_name}", UserWarning)
                     continue  # Skip this release
 
-                release_date = datetime.fromisoformat(
+                release_date = datetime.datetime.fromisoformat(
                     node["createdAt"].replace("Z", "+00:00")
                 )
                 yield Release(version, release_date)
diff --git a/tests/test_releasesource.py b/tests/test_releasesource.py
index 2cd7153..542b4f4 100644
--- a/tests/test_releasesource.py
+++ b/tests/test_releasesource.py
@@ -2,6 +2,7 @@
 import responses
 import warnings
 import datetime
+import os
 from packaging.version import Version
 
 from requires_internet import requires_internet
@@ -182,3 +183,185 @@ def test_integration_releases(self, package_name):
 
         dates = [r.release_date for r in releases if r.release_date is not None]
         assert_is_descending(dates)
+
+
+MOCK_GH_RESPONSE_VALID_ONLY = {
+    "data": {
+        "repository": {
+            "releases": {
+                "pageInfo": {"endCursor": None, "hasNextPage": False},
+                "nodes": [
+                    {"tagName": "2.2.0", "createdAt": "2023-03-03T12:00:00Z"},
+                    {"tagName": "2.1.0", "createdAt": "2023-02-10T09:00:00Z"},
+                    {"tagName": "1.9.0", "createdAt": "2023-01-15T20:00:00Z"},
+                ],
+            }
+        }
+    }
+}
+
+MOCK_GH_RESPONSE_MIXED = {
+    "data": {
+        "repository": {
+            "releases": {
+                "pageInfo": {"endCursor": None, "hasNextPage": False},
+                "nodes": [
+                    {"tagName": "10.0.0", "createdAt": "2024-01-01T12:00:00Z"},
+                    {
+                        "tagName": "not-a-valid-version",
+                        "createdAt": "2024-01-02T12:00:00Z",
+                    },
+                    {"tagName": "9.9.9", "createdAt": "2023-12-15T12:00:00Z"},
+                ],
+            }
+        }
+    }
+}
+
+MOCK_GH_RESPONSE_PAGE1 = {
+    "data": {
+        "repository": {
+            "releases": {
+                "pageInfo": {"endCursor": "CURSOR1", "hasNextPage": True},
+                "nodes": [
+                    {"tagName": "3.0.0", "createdAt": "2024-01-05T12:00:00Z"},
+                    {"tagName": "2.5.0", "createdAt": "2023-12-20T12:00:00Z"},
+                ],
+            }
+        }
+    }
+}
+
+MOCK_GH_RESPONSE_PAGE2 = {
+    "data": {
+        "repository": {
+            "releases": {
+                "pageInfo": {"endCursor": None, "hasNextPage": False},
+                "nodes": [
+                    {"tagName": "2.2.0", "createdAt": "2023-11-10T12:00:00Z"},
+                    {"tagName": "2.0.0", "createdAt": "2023-10-01T12:00:00Z"},
+                ],
+            }
+        }
+    }
+}
+
+
+class TestGitHubReleaseSource:
+    @responses.activate
+    def test_valid_only_versions(self):
+        """Test that valid versions are parsed and returned in descending order."""
+        url = "https://api.github.com/graphql"
+        responses.add(
+            responses.POST,
+            url,
+            json=MOCK_GH_RESPONSE_VALID_ONLY,
+            status=200,
+        )
+
+        token = "FAKE_TOKEN"
+        source = GitHubReleaseSource(token)
+        releases = list(source._get_releases("octocat/Hello-World"))
+
+        # Verify the number of releases.
+        assert len(releases) == 3
+
+        # Check that the versions are correctly parsed.
+        versions = [r.version for r in releases]
+        assert versions == [Version("2.2.0"), Version("2.1.0"), Version("1.9.0")]
+
+        # Verify that the release dates are in descending order.
+        release_dates = [r.release_date for r in releases]
+        assert_is_descending(release_dates)
+        assert release_dates == [
+            datetime.datetime(2023, 3, 3, 12, 0, tzinfo=datetime.timezone.utc),
+            datetime.datetime(2023, 2, 10, 9, 0, tzinfo=datetime.timezone.utc),
+            datetime.datetime(2023, 1, 15, 20, 0, tzinfo=datetime.timezone.utc),
+        ]
+
+    @responses.activate
+    def test_mixed_versions_warning(self):
+        """Test that invalid version strings trigger a warning and are skipped."""
+        url = "https://api.github.com/graphql"
+        responses.add(
+            responses.POST,
+            url,
+            json=MOCK_GH_RESPONSE_MIXED,
+            status=200,
+        )
+
+        token = "FAKE_TOKEN"
+        with pytest.warns(UserWarning, match="Skipping invalid version"):
+            warnings.simplefilter("always")
+            source = GitHubReleaseSource(token)
+            releases = list(source._get_releases("octocat/Hello-World"))
+
+        # Only the valid versions should be returned.
+        assert len(releases) == 2
+        versions = [r.version for r in releases]
+        assert versions == [Version("10.0.0"), Version("9.9.9")]
+
+        release_dates = [r.release_date for r in releases]
+        assert_is_descending(release_dates)
+        assert release_dates == [
+            datetime.datetime(2024, 1, 1, 12, 0, tzinfo=datetime.timezone.utc),
+            datetime.datetime(2023, 12, 15, 12, 0, tzinfo=datetime.timezone.utc),
+        ]
+
+    @responses.activate
+    def test_pagination(self):
+        """
+        Test that pagination is handled correctly by returning all releases from
+        multiple pages in the proper order.
+        """
+        url = "https://api.github.com/graphql"
+        # Simulate two paginated responses.
+        responses.add(
+            responses.POST,
+            url,
+            json=MOCK_GH_RESPONSE_PAGE1,
+            status=200,
+        )
+        responses.add(
+            responses.POST,
+            url,
+            json=MOCK_GH_RESPONSE_PAGE2,
+            status=200,
+        )
+
+        token = "FAKE_TOKEN"
+        source = GitHubReleaseSource(token)
+        releases = list(source._get_releases("octocat/Hello-World"))
+
+        # We expect 4 releases total.
+        assert len(releases) == 4
+
+        # Check the expected version order.
+        expected_versions = [
+            Version("3.0.0"),
+            Version("2.5.0"),
+            Version("2.2.0"),
+            Version("2.0.0"),
+        ]
+        versions = [r.version for r in releases]
+        assert versions == expected_versions
+
+        # Verify that the release dates are in descending order.
+        release_dates = [r.release_date for r in releases]
+        assert_is_descending(release_dates)
+
+    @pytest.mark.skipif(
+        not os.environ.get("GITHUB_TOKEN"), reason="GITHUB_TOKEN not set"
+    )
+    def test_integration_openpathsampling(self):
+        """
+        Integration test using the real GitHub API to fetch releases for the
+        repository openpathsampling/openpathsampling. Checks that at least one
+        release is returned and that the releases are in descending order.
+        """
+        token = os.environ["GITHUB_TOKEN"]
+        source = GitHubReleaseSource(token)
+        releases = list(source._get_releases("openpathsampling/openpathsampling"))
+        assert len(releases) > 0
+        release_dates = [r.release_date for r in releases]
+        assert_is_descending(release_dates)

From 1a6329f3a20ebc801432e8cbc67fede8ca09d0b0 Mon Sep 17 00:00:00 2001
From: "David W.H. Swenson" <david.swenson@omsf.io>
Date: Thu, 3 Apr 2025 13:37:19 -0500
Subject: [PATCH 03/15] cleanup docstrings a bit

---
 src/spec0/releasesource.py | 17 ++++++++---------
 1 file changed, 8 insertions(+), 9 deletions(-)

diff --git a/src/spec0/releasesource.py b/src/spec0/releasesource.py
index ad2df47..91f7cc4 100644
--- a/src/spec0/releasesource.py
+++ b/src/spec0/releasesource.py
@@ -74,17 +74,16 @@ def _get_releases(self, package: str) -> Generator[Release, None, None]:
 
 
 class GitHubReleaseSource(ReleaseSource):
-    """Class to fetch all GitHub releases for a given repository using the GitHub GraphQL API."""
+    """
+    Class to fetch all GitHub releases for a given repository using the GitHub GraphQL API.
 
-    def __init__(self, github_token: str):
-        """
-        Initialize the release source with a GitHub token.
+    Parameters
+    ----------
+    github_token : str
+        Personal access token (PAT) with permissions to query the desired repository.
+    """
 
-        Parameters
-        ----------
-        github_token : str
-            Personal access token (PAT) with permissions to query the desired repository.
-        """
+    def __init__(self, github_token: str):
         self.github_token = github_token
 
     def _get_releases(self, owner_repo: str):

From 0fb2e566f5f80a3b14831292afbaf3d3c6db240f Mon Sep 17 00:00:00 2001
From: "David W.H. Swenson" <david.swenson@omsf.io>
Date: Tue, 8 Apr 2025 18:16:23 -0500
Subject: [PATCH 04/15] Working example with GitHub releases; too bad I need
 tags!

---
 src/spec0/cli.py                    | 24 ++++++++++++++++++------
 src/spec0/data/github-releases.json |  3 +++
 src/spec0/releasefilters.py         |  5 ++++-
 src/spec0/releasesource.py          | 20 ++++++++++++++++++--
 tests/test_releasesource.py         | 12 +++++++-----
 5 files changed, 50 insertions(+), 14 deletions(-)
 create mode 100644 src/spec0/data/github-releases.json

diff --git a/src/spec0/cli.py b/src/spec0/cli.py
index c2bfc9b..aa709b9 100644
--- a/src/spec0/cli.py
+++ b/src/spec0/cli.py
@@ -1,9 +1,14 @@
 import argparse
 import logging
+import os
 
 from functools import partial
 
-from spec0.releasesource import PyPIReleaseSource, CondaReleaseSource
+from spec0.releasesource import (
+    PyPIReleaseSource,
+    CondaReleaseSource,
+    GitHubReleaseSource,
+)
 from spec0.releasefilters import SPEC0StrictDate, SPEC0Quarter
 from spec0.output import terminal_output, json_output, specifier_output
 from spec0.main import main
@@ -55,7 +60,7 @@ def make_parser():
         default=["noarch", "linux-64"],
         help=("Conda architectures to check, only used if conda-channel is specified"),
     )
-    # source.add_argument('--github', action='store_true')
+    source.add_argument("--github", action="store_true")
 
     # filter options
     filterg = parser.add_argument_group(
@@ -116,8 +121,8 @@ def select_source(opts):
     """
     selected_pypi = opts.pypi
     selected_conda = opts.conda_channel is not None
-    # selected_github = opts.github
-    n_selected = sum([selected_pypi, selected_conda])
+    selected_github = opts.github
+    n_selected = sum([selected_pypi, selected_conda, selected_github])
     if n_selected == 0:
         source = None
     elif n_selected > 1:
@@ -128,8 +133,15 @@ def select_source(opts):
         elif selected_conda:
             platforms = [f"{opts.conda_channel}/{arch}" for arch in opts.conda_arch]
             source = [CondaReleaseSource(platforms)]
-        # elif selected_github:
-        #    source = GitHubReleaseSource()
+        elif selected_github:
+            if (token := os.getenv("GITHUB_TOKEN")) is None:
+                raise ValueError(
+                    "GITHUB_TOKEN environment variable must be set to use GitHub "
+                    "releases"
+                )
+
+            source = [GitHubReleaseSource(token)]
+
     return source
 
 
diff --git a/src/spec0/data/github-releases.json b/src/spec0/data/github-releases.json
new file mode 100644
index 0000000..7a84d06
--- /dev/null
+++ b/src/spec0/data/github-releases.json
@@ -0,0 +1,3 @@
+{
+    "rust":  "rust-lang/rust"
+}
diff --git a/src/spec0/releasefilters.py b/src/spec0/releasefilters.py
index c26dbca..8ba4181 100644
--- a/src/spec0/releasefilters.py
+++ b/src/spec0/releasefilters.py
@@ -66,7 +66,10 @@ def _get_n_months(self, package: str):
     def _get_minimum_supported(self, package: str, releases: Iterable[Release]):
         oldest_minor_release = get_oldest_minor_release(releases)
 
-        max_minor_release = max(oldest_minor_release)
+        try:
+            max_minor_release = max(oldest_minor_release)
+        except ValueError:  # no releases found
+            raise RuntimeError(f"No releases found for package '{package}'")
         # always support at least the most recent minor release
         supported = {max_minor_release: oldest_minor_release[max_minor_release]}
 
diff --git a/src/spec0/releasesource.py b/src/spec0/releasesource.py
index c9eefbb..a9f2731 100644
--- a/src/spec0/releasesource.py
+++ b/src/spec0/releasesource.py
@@ -4,6 +4,8 @@
 import requests
 import warnings
 from packaging.version import Version, InvalidVersion
+import importlib.resources
+import collections
 
 from typing import Generator
 
@@ -80,7 +82,8 @@ def _get_releases(self, package: str) -> Generator[Release, None, None]:
 
 class GitHubReleaseSource(ReleaseSource):
     """
-    Class to fetch all GitHub releases for a given repository using the GitHub GraphQL API.
+    Class to fetch all GitHub releases for a given repository using the GitHub GraphQL
+    API.
 
     Parameters
     ----------
@@ -90,8 +93,21 @@ class GitHubReleaseSource(ReleaseSource):
 
     def __init__(self, github_token: str):
         self.github_token = github_token
+        trav = importlib.resources.files("spec0")
+        jsonstr = trav.joinpath("data/github-releases.json").read_text()
+        self.canonical_sources = json.loads(jsonstr)
 
-    def _get_releases(self, owner_repo: str):
+    def _get_releases(self, package: str):
+        if collections.Counter(package).get("/") == 1:
+            owner_repo = package
+        elif package in self.canonical_sources:
+            owner_repo = self.canonical_sources[package]
+        else:
+            raise ValueError(f"GitHub repository for package '{package}' not found")
+
+        yield from self._get_releases_owner_repo(owner_repo)
+
+    def _get_releases_owner_repo(self, owner_repo: str):
         """
         Generate all releases for a repository in descending order of
         creation date (most recent first).
diff --git a/tests/test_releasesource.py b/tests/test_releasesource.py
index 542b4f4..0cda56b 100644
--- a/tests/test_releasesource.py
+++ b/tests/test_releasesource.py
@@ -248,8 +248,9 @@ def test_integration_releases(self, package_name):
 
 
 class TestGitHubReleaseSource:
+    @pytest.mark.parametrize("inputstr", ["octohello", "octocat/Hello-World"])
     @responses.activate
-    def test_valid_only_versions(self):
+    def test_valid_only_versions(self, inputstr):
         """Test that valid versions are parsed and returned in descending order."""
         url = "https://api.github.com/graphql"
         responses.add(
@@ -261,7 +262,8 @@ def test_valid_only_versions(self):
 
         token = "FAKE_TOKEN"
         source = GitHubReleaseSource(token)
-        releases = list(source._get_releases("octocat/Hello-World"))
+        source.canonical_sources["octohello"] = "octocat/Hello-World"
+        releases = list(source.get_releases(inputstr))
 
         # Verify the number of releases.
         assert len(releases) == 3
@@ -294,7 +296,7 @@ def test_mixed_versions_warning(self):
         with pytest.warns(UserWarning, match="Skipping invalid version"):
             warnings.simplefilter("always")
             source = GitHubReleaseSource(token)
-            releases = list(source._get_releases("octocat/Hello-World"))
+            releases = list(source._get_releases_owner_repo("octocat/Hello-World"))
 
         # Only the valid versions should be returned.
         assert len(releases) == 2
@@ -331,7 +333,7 @@ def test_pagination(self):
 
         token = "FAKE_TOKEN"
         source = GitHubReleaseSource(token)
-        releases = list(source._get_releases("octocat/Hello-World"))
+        releases = list(source._get_releases_owner_repo("octocat/Hello-World"))
 
         # We expect 4 releases total.
         assert len(releases) == 4
@@ -361,7 +363,7 @@ def test_integration_openpathsampling(self):
         """
         token = os.environ["GITHUB_TOKEN"]
         source = GitHubReleaseSource(token)
-        releases = list(source._get_releases("openpathsampling/openpathsampling"))
+        releases = list(source.get_releases("openpathsampling/openpathsampling"))
         assert len(releases) > 0
         release_dates = [r.release_date for r in releases]
         assert_is_descending(release_dates)

From 92b4746b2396ca0905aa02058ea01c22d1793d13 Mon Sep 17 00:00:00 2001
From: "David W.H. Swenson" <david.swenson@omsf.io>
Date: Tue, 8 Apr 2025 19:16:25 -0500
Subject: [PATCH 05/15] Switch so that we're actually doing tags

---
 src/spec0/data/github-releases.json |  3 +-
 src/spec0/releasesource.py          | 31 +++++++++++---
 tests/test_releasesource.py         | 63 ++++++++++++++++++++---------
 3 files changed, 71 insertions(+), 26 deletions(-)

diff --git a/src/spec0/data/github-releases.json b/src/spec0/data/github-releases.json
index 7a84d06..c0ac236 100644
--- a/src/spec0/data/github-releases.json
+++ b/src/spec0/data/github-releases.json
@@ -1,3 +1,4 @@
 {
-    "rust":  "rust-lang/rust"
+    "rust":  "rust-lang/rust",
+    "python": "python/cpython"
 }
diff --git a/src/spec0/releasesource.py b/src/spec0/releasesource.py
index a9f2731..c94acf6 100644
--- a/src/spec0/releasesource.py
+++ b/src/spec0/releasesource.py
@@ -134,14 +134,28 @@ def _get_releases_owner_repo(self, owner_repo: str):
         query = """
         query($owner: String!, $repo: String!, $after: String) {
           repository(owner: $owner, name: $repo) {
-            releases(first: 100, after: $after, orderBy: {field: CREATED_AT, direction: DESC}) {
+            refs(after:$after, first:100, refPrefix:"refs/tags/", orderBy:{field:TAG_COMMIT_DATE, direction:DESC}) {
+
               pageInfo {
                 endCursor
                 hasNextPage
               }
+
               nodes {
-                tagName
-                createdAt
+                name
+
+                target {
+                  # looks like this is what you get if you create the tag in the UI
+                  ... on Commit {
+                    committedDate
+                  }
+                  # and this is if you don't? or something?
+                  ... on Tag {
+                    tagger {
+                      date
+                    }
+                  }
+                }
               }
             }
           }
@@ -169,18 +183,23 @@ def _get_releases_owner_repo(self, owner_repo: str):
             response.raise_for_status()
 
             data = response.json()
-            releases_data = data["data"]["repository"]["releases"]
+            releases_data = data["data"]["repository"]["refs"]
 
             for node in releases_data["nodes"]:
-                tag_name = node["tagName"]
+                tag_name = node["name"]
                 try:
                     version = Version(tag_name)
                 except InvalidVersion:
                     warnings.warn(f"Skipping invalid version: {tag_name}", UserWarning)
                     continue  # Skip this release
 
+                if "tagger" in node["target"]:
+                    datestr = node["target"]["tagger"]["date"]
+                else:
+                    datestr = node["target"]["committedDate"]
+
                 release_date = datetime.datetime.fromisoformat(
-                    node["createdAt"].replace("Z", "+00:00")
+                    datestr.replace("Z", "+00:00")
                 )
                 yield Release(version, release_date)
 
diff --git a/tests/test_releasesource.py b/tests/test_releasesource.py
index 0cda56b..ecb80ef 100644
--- a/tests/test_releasesource.py
+++ b/tests/test_releasesource.py
@@ -188,12 +188,21 @@ def test_integration_releases(self, package_name):
 MOCK_GH_RESPONSE_VALID_ONLY = {
     "data": {
         "repository": {
-            "releases": {
+            "refs": {
                 "pageInfo": {"endCursor": None, "hasNextPage": False},
                 "nodes": [
-                    {"tagName": "2.2.0", "createdAt": "2023-03-03T12:00:00Z"},
-                    {"tagName": "2.1.0", "createdAt": "2023-02-10T09:00:00Z"},
-                    {"tagName": "1.9.0", "createdAt": "2023-01-15T20:00:00Z"},
+                    {
+                        "name": "v2.2.0",
+                        "target": {"committedDate": "2023-03-03T12:00:00Z"},
+                    },
+                    {
+                        "name": "2.1.0",
+                        "target": {"tagger": {"date": "2023-02-10T09:00:00Z"}},
+                    },
+                    {
+                        "name": "1.9.0",
+                        "target": {"committedDate": "2023-01-15T20:00:00Z"},
+                    },
                 ],
             }
         }
@@ -203,15 +212,21 @@ def test_integration_releases(self, package_name):
 MOCK_GH_RESPONSE_MIXED = {
     "data": {
         "repository": {
-            "releases": {
+            "refs": {
                 "pageInfo": {"endCursor": None, "hasNextPage": False},
                 "nodes": [
-                    {"tagName": "10.0.0", "createdAt": "2024-01-01T12:00:00Z"},
                     {
-                        "tagName": "not-a-valid-version",
-                        "createdAt": "2024-01-02T12:00:00Z",
+                        "name": "10.0.0",
+                        "target": {"committedDate": "2024-01-01T12:00:00Z"},
+                    },
+                    {
+                        "name": "not-a-valid-version",
+                        "target": {"committedDate": "2024-01-02T12:00:00Z"},
+                    },
+                    {
+                        "name": "9.9.9",
+                        "target": {"committedDate": "2023-12-15T12:00:00Z"},
                     },
-                    {"tagName": "9.9.9", "createdAt": "2023-12-15T12:00:00Z"},
                 ],
             }
         }
@@ -221,11 +236,17 @@ def test_integration_releases(self, package_name):
 MOCK_GH_RESPONSE_PAGE1 = {
     "data": {
         "repository": {
-            "releases": {
+            "refs": {
                 "pageInfo": {"endCursor": "CURSOR1", "hasNextPage": True},
                 "nodes": [
-                    {"tagName": "3.0.0", "createdAt": "2024-01-05T12:00:00Z"},
-                    {"tagName": "2.5.0", "createdAt": "2023-12-20T12:00:00Z"},
+                    {
+                        "name": "3.0.0",
+                        "target": {"committedDate": "2024-01-05T12:00:00Z"},
+                    },
+                    {
+                        "name": "2.5.0",
+                        "target": {"committedDate": "2023-12-20T12:00:00Z"},
+                    },
                 ],
             }
         }
@@ -235,11 +256,17 @@ def test_integration_releases(self, package_name):
 MOCK_GH_RESPONSE_PAGE2 = {
     "data": {
         "repository": {
-            "releases": {
+            "refs": {
                 "pageInfo": {"endCursor": None, "hasNextPage": False},
                 "nodes": [
-                    {"tagName": "2.2.0", "createdAt": "2023-11-10T12:00:00Z"},
-                    {"tagName": "2.0.0", "createdAt": "2023-10-01T12:00:00Z"},
+                    {
+                        "name": "2.2.0",
+                        "target": {"committedDate": "2023-11-10T12:00:00Z"},
+                    },
+                    {
+                        "name": "2.0.0",
+                        "target": {"committedDate": "2023-10-01T12:00:00Z"},
+                    },
                 ],
             }
         }
@@ -355,7 +382,7 @@ def test_pagination(self):
     @pytest.mark.skipif(
         not os.environ.get("GITHUB_TOKEN"), reason="GITHUB_TOKEN not set"
     )
-    def test_integration_openpathsampling(self):
+    def test_integration_python(self):
         """
         Integration test using the real GitHub API to fetch releases for the
         repository openpathsampling/openpathsampling. Checks that at least one
@@ -363,7 +390,5 @@ def test_integration_openpathsampling(self):
         """
         token = os.environ["GITHUB_TOKEN"]
         source = GitHubReleaseSource(token)
-        releases = list(source.get_releases("openpathsampling/openpathsampling"))
+        releases = list(source.get_releases("python"))
         assert len(releases) > 0
-        release_dates = [r.release_date for r in releases]
-        assert_is_descending(release_dates)

From 39eb3281db0f113ceaac33444f70be937a681086 Mon Sep 17 00:00:00 2001
From: "David W.H. Swenson" <david.swenson@omsf.io>
Date: Tue, 8 Apr 2025 19:42:26 -0500
Subject: [PATCH 06/15] Add GITHUB_TOKEN to pytest

---
 .github/workflows/ci.yaml | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index dc77344..e0e2739 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -30,6 +30,8 @@ jobs:
 
       - name: Run tests
         run: python -m pytest --cov -v
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}  # needed for some tests
 
       - name: Upload coverage
         uses: codecov/codecov-action@v5

From af1972bae7b56a75a03281d01b7db9ef4b1e438e Mon Sep 17 00:00:00 2001
From: "David W.H. Swenson" <david.swenson@omsf.io>
Date: Wed, 9 Apr 2025 15:27:33 -0500
Subject: [PATCH 07/15] DefaultReleaseSource, and CLI talks to
 GitHubReleaseSource

---
 src/spec0/cli.py            |  16 ++---
 src/spec0/main.py           |  24 ++-----
 src/spec0/releasesource.py  |  75 +++++++++++++++++++-
 tests/test_main.py          |  45 ++----------
 tests/test_releasesource.py | 134 ++++++++++++++++++++++++++++++++++++
 5 files changed, 224 insertions(+), 70 deletions(-)

diff --git a/src/spec0/cli.py b/src/spec0/cli.py
index aa709b9..ce4fd8e 100644
--- a/src/spec0/cli.py
+++ b/src/spec0/cli.py
@@ -8,6 +8,7 @@
     PyPIReleaseSource,
     CondaReleaseSource,
     GitHubReleaseSource,
+    DefaultReleaseSource,
 )
 from spec0.releasefilters import SPEC0StrictDate, SPEC0Quarter
 from spec0.output import terminal_output, json_output, specifier_output
@@ -123,24 +124,19 @@ def select_source(opts):
     selected_conda = opts.conda_channel is not None
     selected_github = opts.github
     n_selected = sum([selected_pypi, selected_conda, selected_github])
+    token = os.getenv("GITHUB_TOKEN")
     if n_selected == 0:
-        source = None
+        source = DefaultReleaseSource(token)
     elif n_selected > 1:
         raise ValueError("Only one source can be selected")
     else:
         if selected_pypi:
-            source = [PyPIReleaseSource()]
+            source = PyPIReleaseSource()
         elif selected_conda:
             platforms = [f"{opts.conda_channel}/{arch}" for arch in opts.conda_arch]
-            source = [CondaReleaseSource(platforms)]
+            source = CondaReleaseSource(platforms)
         elif selected_github:
-            if (token := os.getenv("GITHUB_TOKEN")) is None:
-                raise ValueError(
-                    "GITHUB_TOKEN environment variable must be set to use GitHub "
-                    "releases"
-                )
-
-            source = [GitHubReleaseSource(token)]
+            source = GitHubReleaseSource(token)
 
     return source
 
diff --git a/src/spec0/main.py b/src/spec0/main.py
index b4b1928..d1f803b 100644
--- a/src/spec0/main.py
+++ b/src/spec0/main.py
@@ -1,4 +1,3 @@
-from spec0.releasesource import PyPIReleaseSource, CondaReleaseSource
 from spec0.releasefilters import SPEC0StrictDate
 
 import logging
@@ -6,28 +5,20 @@
 _logger = logging.getLogger(__name__)
 
 
-def default_sources():
-    """Default release sources if none are provided."""
-    return [
-        PyPIReleaseSource(),
-        CondaReleaseSource(["conda-forge/noarch", "conda-forge/linux-64"]),
-    ]
-
-
 def default_filter():
     """Default support filter if none is provided."""
     return SPEC0StrictDate()
 
 
-def main(package, sources=None, filter_=None):
+def main(package, source, filter_=None):
     """Main function to get release info for a package.
 
     Parameters
     ----------
     package : str
         The name of the package to get release info for.
-    sources : list, optional
-        A list of release sources to use. If None, default sources are used.
+    source : ReleaseSource
+        The source to use for getting release info.
     filter_ : ReleaseFilter, optional
         A release filter to use. If None, default filter is used.
 
@@ -42,17 +33,10 @@ def main(package, sources=None, filter_=None):
         (datetime) release date of the release, and "drop-date" is the
         (datetime) drop date of the release, according to the input filter.
     """
-    if sources is None:
-        sources = default_sources()
-
     if filter_ is None:
         filter_ = default_filter()
 
-    # we take the releases from the first source that has them
-    for source in sources:
-        if releases := source.get_releases(package):
-            break
-
+    releases = source.get_releases(package)
     filtered = filter_.filter(package, releases)
     result = {
         "package": package,
diff --git a/src/spec0/releasesource.py b/src/spec0/releasesource.py
index c94acf6..6a7c439 100644
--- a/src/spec0/releasesource.py
+++ b/src/spec0/releasesource.py
@@ -1,6 +1,7 @@
 import dataclasses
 import datetime
 import json
+import os
 import requests
 import warnings
 from packaging.version import Version, InvalidVersion
@@ -24,6 +25,10 @@ class Release:
     release_date: datetime.datetime
 
 
+class NoReleaseFound(Exception):
+    pass
+
+
 class ReleaseSource:
     """ABC for a source of package releases."""
 
@@ -44,7 +49,13 @@ def _get_releases(self, package: str) -> Generator[Release, None, None]:
         url = f"https://pypi.org/pypi/{package}/json"
         _logger.debug(f"Fetching {url}")
         response = requests.get(url)
-        response.raise_for_status()
+        try:
+            response.raise_for_status()
+        except requests.exceptions.HTTPError as e:
+            if response.status_code == 404:
+                raise NoReleaseFound(f"No PyPI package '{package}'") from e
+            else:
+                raise
         data = response.json()
 
         releases_data = data.get("releases", {})
@@ -76,6 +87,8 @@ def _get_releases(self, package: str) -> Generator[Release, None, None]:
                 release_list.append(release)
 
         release_list.sort(key=lambda r: r.release_date, reverse=True)
+        if not release_list:
+            raise NoReleaseFound(f"No releases found for package '{package}'")
         for release in release_list:
             yield release
 
@@ -97,13 +110,22 @@ def __init__(self, github_token: str):
         jsonstr = trav.joinpath("data/github-releases.json").read_text()
         self.canonical_sources = json.loads(jsonstr)
 
+    def is_github_package(self, package: str) -> bool:
+        """Check if the package is a GitHub package."""
+        if collections.Counter(package).get("/") == 1:
+            return True
+        elif package in self.canonical_sources:
+            return True
+        else:
+            return False
+
     def _get_releases(self, package: str):
         if collections.Counter(package).get("/") == 1:
             owner_repo = package
         elif package in self.canonical_sources:
             owner_repo = self.canonical_sources[package]
         else:
-            raise ValueError(f"GitHub repository for package '{package}' not found")
+            raise NoReleaseFound(f"GitHub repository for package '{package}' not found")
 
         yield from self._get_releases_owner_repo(owner_repo)
 
@@ -162,6 +184,16 @@ def _get_releases_owner_repo(self, owner_repo: str):
         }
         """
 
+        token = self.github_token
+        if token is None:
+            token = os.environ.get("GITHUB_TOKEN")
+
+        if token is None:
+            raise ValueError(
+                "GitHub token not provided. Please set the GITHUB_TOKEN "
+                "environment variable."
+            )
+
         url = "https://api.github.com/graphql"
         headers = {
             "Authorization": f"Bearer {self.github_token}",
@@ -266,5 +298,44 @@ def _get_releases(self, package):
             key=lambda r: (r.release_date is None, r.release_date), reverse=True
         )
 
+        if not releases:
+            raise NoReleaseFound(f"No releases found for package '{package}'")
+
         for release_obj in releases:
             yield release_obj
+
+
+class DefaultReleaseSource(ReleaseSource):
+    """
+    Release source that tries (1) GitHub releases; (2) PyPI; (3) conda-forge.
+
+    Parameters
+    ----------
+    github_token : str
+        Personal access token (PAT) with permissions to query the desired repository.
+    """
+
+    def __init__(self, github_token: str = None):
+        self.github_source = GitHubReleaseSource(github_token)
+        self.pypi_source = PyPIReleaseSource()
+        self.conda_source = CondaReleaseSource(
+            [
+                "conda-forge/linux-64",
+                "conda-forge/noarch",
+            ]
+        )
+
+    def _get_releases(self, package: str) -> Generator[Release, None, None]:
+        # check whether the package should be a GitHub release, try GitHub if so
+        if self.github_source.is_github_package(package):
+            yield from self.github_source.get_releases(package)
+            return
+
+        try:
+            yield from self.pypi_source.get_releases(package)
+        except NoReleaseFound:  # TODO: handle exception
+            pass
+        else:
+            return
+
+        yield from self.conda_source.get_releases(package)
diff --git a/tests/test_main.py b/tests/test_main.py
index 83467b3..12fbcd9 100644
--- a/tests/test_main.py
+++ b/tests/test_main.py
@@ -1,7 +1,7 @@
 import datetime
 from packaging.version import Version
 
-from spec0.releasesource import PyPIReleaseSource, CondaReleaseSource, Release
+from spec0.releasesource import Release, DefaultReleaseSource
 from spec0.releasefilters import SPEC0StrictDate
 
 from spec0.main import *
@@ -34,15 +34,6 @@ def drop_date(self, package, release):
         return datetime.datetime(2021, 1, 1)
 
 
-def test_default_sources():
-    sources = default_sources()
-    assert isinstance(sources, list)
-    assert len(sources) == 2
-
-    assert isinstance(sources[0], PyPIReleaseSource)
-    assert isinstance(sources[1], CondaReleaseSource)
-
-
 def test_default_filter():
     filter_obj = default_filter()
     assert isinstance(filter_obj, SPEC0StrictDate)
@@ -50,20 +41,13 @@ def test_default_filter():
     assert filter_obj.python_override is True
 
 
-def test_main_uses_first_source_with_releases():
+def test_main():
     v = Version("1.0")
     release_date = datetime.datetime(2020, 1, 1)
     dummy_release = Release(v, release_date)
-
-    # The first source returns a valid releases dict.
-    # The second source should not be used.
-    source1 = DummySource({"r1": dummy_release})
-    v2 = Version("2.0")
-    source2 = DummySource({"r2": Release(v2, datetime.datetime(2020, 2, 2))})
-
+    source = DummySource({"r1": dummy_release})
     filter_obj = DummyFilter()
-    result = main("testpkg", sources=[source1, source2], filter_=filter_obj)
-
+    result = main("testpkg", source=source, filter_=filter_obj)
     assert result["package"] == "testpkg"
     assert isinstance(result["releases"], list)
     assert len(result["releases"]) == 1
@@ -73,25 +57,10 @@ def test_main_uses_first_source_with_releases():
     assert release_info["drop-date"] == datetime.datetime(2021, 1, 1)
 
 
-def test_main_uses_second_source_when_first_returns_none():
-    v = Version("1.0")
-    release_date = datetime.datetime(2020, 1, 1)
-    dummy_release = Release(v, release_date)
-
-    source1 = DummySource(None)
-    source2 = DummySource({"r1": dummy_release})
-
-    filter_obj = DummyFilter()
-    result = main("testpkg", sources=[source1, source2], filter_=filter_obj)
-
-    assert result["package"] == "testpkg"
-    assert isinstance(result["releases"], list)
-    assert len(result["releases"]) == 1
-
-
-def test_main_default():
+def test_main_integration():
     # smoke test for integration with default params
-    results = main("numpy")
+    source = DefaultReleaseSource()
+    results = main("numpy", source)
     assert results["package"] == "numpy"
     assert len(results["releases"]) > 0
     recent_release = results["releases"][0]
diff --git a/tests/test_releasesource.py b/tests/test_releasesource.py
index ecb80ef..17f41f0 100644
--- a/tests/test_releasesource.py
+++ b/tests/test_releasesource.py
@@ -3,6 +3,8 @@
 import warnings
 import datetime
 import os
+from contextlib import ExitStack
+from unittest.mock import patch
 from packaging.version import Version
 
 from requires_internet import requires_internet
@@ -392,3 +394,135 @@ def test_integration_python(self):
         source = GitHubReleaseSource(token)
         releases = list(source.get_releases("python"))
         assert len(releases) > 0
+
+
+def make_release(version: str, date_str: str):
+    dt = datetime.datetime.fromisoformat(date_str).replace(tzinfo=datetime.timezone.utc)
+    return Release(Version(version), dt)
+
+
+class TestDefaultReleaseSource:
+    def test_get_releases_github(self):
+        with ExitStack() as stack:
+            mock_github_cls = stack.enter_context(
+                patch("spec0.releasesource.GitHubReleaseSource")
+            )
+            mock_pypi_cls = stack.enter_context(
+                patch("spec0.releasesource.PyPIReleaseSource")
+            )
+            mock_conda_cls = stack.enter_context(
+                patch("spec0.releasesource.CondaReleaseSource")
+            )
+
+            mock_github = mock_github_cls.return_value
+            mock_github.is_github_package.return_value = True
+            mock_github.get_releases.return_value = iter(
+                [make_release("1.0.0", "2023-01-01T00:00:00")]
+            )
+
+            source = DefaultReleaseSource("fake-token")
+            releases = list(source.get_releases("somegithub/repo"))
+
+            assert len(releases) == 1
+            assert releases[0].version == Version("1.0.0")
+            mock_github.get_releases.assert_called_once()
+            mock_pypi_cls.return_value.get_releases.assert_not_called()
+            mock_conda_cls.return_value.get_releases.assert_not_called()
+
+    def test_get_releases_pypi(self):
+        with ExitStack() as stack:
+            mock_github_cls = stack.enter_context(
+                patch("spec0.releasesource.GitHubReleaseSource")
+            )
+            mock_pypi_cls = stack.enter_context(
+                patch("spec0.releasesource.PyPIReleaseSource")
+            )
+            mock_conda_cls = stack.enter_context(
+                patch("spec0.releasesource.CondaReleaseSource")
+            )
+
+            mock_github = mock_github_cls.return_value
+            mock_github.is_github_package.return_value = False
+
+            mock_pypi = mock_pypi_cls.return_value
+            mock_pypi.get_releases.return_value = iter(
+                [make_release("2.0.0", "2022-01-01T00:00:00")]
+            )
+
+            source = DefaultReleaseSource("fake-token")
+            releases = list(source.get_releases("non-github-package"))
+
+            assert len(releases) == 1
+            assert releases[0].version == Version("2.0.0")
+            mock_github.get_releases.assert_not_called()
+            mock_pypi.get_releases.assert_called_once()
+            mock_conda_cls.return_value.get_releases.assert_not_called()
+
+    def test_get_releases_conda(self):
+        with ExitStack() as stack:
+            mock_github_cls = stack.enter_context(
+                patch("spec0.releasesource.GitHubReleaseSource")
+            )
+            mock_pypi_cls = stack.enter_context(
+                patch("spec0.releasesource.PyPIReleaseSource")
+            )
+            mock_conda_cls = stack.enter_context(
+                patch("spec0.releasesource.CondaReleaseSource")
+            )
+
+            mock_github = mock_github_cls.return_value
+            mock_github.is_github_package.return_value = False
+
+            mock_pypi = mock_pypi_cls.return_value
+            mock_pypi.get_releases.side_effect = NoReleaseFound("PyPI failed")
+
+            mock_conda = mock_conda_cls.return_value
+            mock_conda.get_releases.return_value = iter(
+                [make_release("3.0.0", "2021-01-01T00:00:00")]
+            )
+
+            source = DefaultReleaseSource("fake-token")
+            releases = list(source.get_releases("fallback-package"))
+
+            assert len(releases) == 1
+            assert releases[0].version == Version("3.0.0")
+            mock_github.get_releases.assert_not_called()
+            mock_pypi.get_releases.assert_called_once()
+            mock_conda.get_releases.assert_called_once()
+
+    def test_get_releases_fail(self):
+        with ExitStack() as stack:
+            mock_github_cls = stack.enter_context(
+                patch("spec0.releasesource.GitHubReleaseSource")
+            )
+            mock_pypi_cls = stack.enter_context(
+                patch("spec0.releasesource.PyPIReleaseSource")
+            )
+            mock_conda_cls = stack.enter_context(
+                patch("spec0.releasesource.CondaReleaseSource")
+            )
+
+            mock_github = mock_github_cls.return_value
+            mock_github.is_github_package.return_value = False
+
+            mock_pypi = mock_pypi_cls.return_value
+            mock_pypi.get_releases.side_effect = NoReleaseFound("PyPI failed")
+
+            mock_conda = mock_conda_cls.return_value
+            mock_conda.get_releases.side_effect = NoReleaseFound("Conda failed")
+
+            source = DefaultReleaseSource("fake-token")
+
+            with pytest.raises(NoReleaseFound, match="Conda failed"):
+                list(source.get_releases("bad-package"))
+
+    def test_github_token_required(self, monkeypatch):
+        """Test that a ValueError is raised when no GitHub token is provided."""
+        # Ensure environment is clean
+        monkeypatch.delenv("GITHUB_TOKEN", raising=False)
+
+        # This will trigger the GitHub release path due to the slash
+        source = DefaultReleaseSource(github_token=None)
+
+        with pytest.raises(ValueError, match="GitHub token not provided"):
+            list(source.get_releases("someuser/someproject"))

From ab4bf27f944d111fc488a053b75019bcc2bfb24f Mon Sep 17 00:00:00 2001
From: "David W.H. Swenson" <david.swenson@omsf.io>
Date: Wed, 9 Apr 2025 15:29:37 -0500
Subject: [PATCH 08/15] Add MANIFEST

---
 MANIFEST.in | 2 ++
 1 file changed, 2 insertions(+)
 create mode 100644 MANIFEST.in

diff --git a/MANIFEST.in b/MANIFEST.in
new file mode 100644
index 0000000..c72fd0c
--- /dev/null
+++ b/MANIFEST.in
@@ -0,0 +1,2 @@
+include LICENSE
+include src/spec0/data/*.json

From 04c271dcb5a733449dbf53467ba7ba4e03cef0a7 Mon Sep 17 00:00:00 2001
From: "David W.H. Swenson" <david.swenson@omsf.io>
Date: Wed, 9 Apr 2025 15:51:50 -0500
Subject: [PATCH 09/15] Smoke test all known GitHub repos

---
 tests/test_releasesource.py | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/tests/test_releasesource.py b/tests/test_releasesource.py
index 17f41f0..3b80d46 100644
--- a/tests/test_releasesource.py
+++ b/tests/test_releasesource.py
@@ -384,7 +384,7 @@ def test_pagination(self):
     @pytest.mark.skipif(
         not os.environ.get("GITHUB_TOKEN"), reason="GITHUB_TOKEN not set"
     )
-    def test_integration_python(self):
+    def test_integration(self):
         """
         Integration test using the real GitHub API to fetch releases for the
         repository openpathsampling/openpathsampling. Checks that at least one
@@ -392,8 +392,9 @@ def test_integration_python(self):
         """
         token = os.environ["GITHUB_TOKEN"]
         source = GitHubReleaseSource(token)
-        releases = list(source.get_releases("python"))
-        assert len(releases) > 0
+        for package in source.canonical_sources:
+            releases = list(source.get_releases(package))
+            assert len(releases) > 0
 
 
 def make_release(version: str, date_str: str):

From 9d8009b1cf8a2241b21238eeeb649695c5a56dd4 Mon Sep 17 00:00:00 2001
From: "David W.H. Swenson" <david.swenson@omsf.io>
Date: Wed, 9 Apr 2025 16:11:12 -0500
Subject: [PATCH 10/15] add test for is_github_package

---
 tests/test_releasesource.py | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/tests/test_releasesource.py b/tests/test_releasesource.py
index 3b80d46..bcb8554 100644
--- a/tests/test_releasesource.py
+++ b/tests/test_releasesource.py
@@ -396,6 +396,25 @@ def test_integration(self):
             releases = list(source.get_releases(package))
             assert len(releases) > 0
 
+    @pytest.mark.parametrize(
+        "package,expected",
+        [
+            ("owner/repo", True),
+            ("python", True),
+            ("package-without-slash", False),
+            ("too/many/slashes", False),
+            ("", False),
+        ],
+    )
+    def test_is_github_package(self, package, expected):
+        """Test the is_github_package method with various inputs."""
+        source = GitHubReleaseSource("FAKE_TOKEN")
+        # Ensure the canonical_sources has expected entries
+        source.canonical_sources = {"python": "python/cpython"}
+
+        result = source.is_github_package(package)
+        assert result == expected
+
 
 def make_release(version: str, date_str: str):
     dt = datetime.datetime.fromisoformat(date_str).replace(tzinfo=datetime.timezone.utc)

From c964e1d8e65f9abf365ed773a25e409306514492 Mon Sep 17 00:00:00 2001
From: "David W.H. Swenson" <david.swenson@omsf.io>
Date: Wed, 9 Apr 2025 17:38:53 -0500
Subject: [PATCH 11/15] Add TestPyPIReleaseSource.test_http_error_responses

---
 tests/test_releasesource.py | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/tests/test_releasesource.py b/tests/test_releasesource.py
index bcb8554..aad8eda 100644
--- a/tests/test_releasesource.py
+++ b/tests/test_releasesource.py
@@ -88,6 +88,28 @@ def test_mixed_versions_warning(self):
             datetime.datetime(2023, 12, 15, 12, 0, tzinfo=datetime.timezone.utc),
         ]
 
+    @pytest.mark.parametrize(
+        "status_code,exception_class",
+        [
+            (404, NoReleaseFound),
+            (503, requests.HTTPError),
+        ],
+    )
+    @responses.activate
+    def test_http_error_responses(self, status_code, exception_class):
+        url = "https://pypi.org/pypi/nonexistent-package/json"
+        responses.add(
+            method=responses.GET,
+            url=url,
+            body=f"Error {status_code}",
+            status=status_code,
+        )
+
+        source = PyPIReleaseSource()
+
+        with pytest.raises(exception_class):
+            list(source.get_releases("nonexistent-package"))
+
     @pytest.mark.parametrize("package_name", ["pandas", "numpy", "scipy"])
     @requires_internet
     def test_integration_packages(self, package_name):

From d0db1071ccfe56c7e4ec7625864cca41d386a2f0 Mon Sep 17 00:00:00 2001
From: "David W.H. Swenson" <david.swenson@omsf.io>
Date: Wed, 9 Apr 2025 18:09:59 -0500
Subject: [PATCH 12/15] Add tests that we raise NoReleaseFound

---
 tests/test_releasesource.py | 38 +++++++++++++++++++++++++++++++++++++
 1 file changed, 38 insertions(+)

diff --git a/tests/test_releasesource.py b/tests/test_releasesource.py
index aad8eda..8c8d66d 100644
--- a/tests/test_releasesource.py
+++ b/tests/test_releasesource.py
@@ -110,6 +110,29 @@ def test_http_error_responses(self, status_code, exception_class):
         with pytest.raises(exception_class):
             list(source.get_releases("nonexistent-package"))
 
+    @responses.activate
+    def test_get_release_no_release(self):
+        """
+        Test that the PyPIReleaseSource correctly handles packages that exist but have no releases.
+        It should raise a NoReleaseFound exception.
+        """
+        url = "https://pypi.org/pypi/package-with-no-releases/json"
+        # Create a mock response with an empty releases dictionary
+        responses.add(
+            method=responses.GET,
+            url=url,
+            json={"releases": {}},
+            status=200,
+        )
+
+        source = PyPIReleaseSource()
+
+        with pytest.raises(
+            NoReleaseFound,
+            match="No releases found for package 'package-with-no-releases'",
+        ):
+            list(source.get_releases("package-with-no-releases"))
+
     @pytest.mark.parametrize("package_name", ["pandas", "numpy", "scipy"])
     @requires_internet
     def test_integration_packages(self, package_name):
@@ -437,6 +460,21 @@ def test_is_github_package(self, package, expected):
         result = source.is_github_package(package)
         assert result == expected
 
+    @pytest.mark.parametrize(
+        "package",
+        [
+            "unknown-package",
+            "too/many/slashes",
+        ],
+    )
+    def test_get_releases_not_found(self, package):
+        source = GitHubReleaseSource("FAKE_TOKEN")
+        source.canonical_sources = {"python": "python/cpython"}
+
+        expected_message = f"GitHub repository for package '{package}' not found"
+        with pytest.raises(NoReleaseFound, match=expected_message):
+            list(source._get_releases(package))
+
 
 def make_release(version: str, date_str: str):
     dt = datetime.datetime.fromisoformat(date_str).replace(tzinfo=datetime.timezone.utc)

From 7af89e95c0420fc23e249e5f4dff4322eef868b7 Mon Sep 17 00:00:00 2001
From: "David W.H. Swenson" <david.swenson@omsf.io>
Date: Wed, 9 Apr 2025 18:51:14 -0500
Subject: [PATCH 13/15] Finish up NoReleaseFound, and add tests

---
 src/spec0/releasefilters.py  |  6 +++---
 src/spec0/releasesource.py   |  8 ++++++++
 tests/test_releasefilters.py | 19 +++++++++++++++++++
 tests/test_releasesource.py  | 31 +++++++++++++++++++++++++++++++
 4 files changed, 61 insertions(+), 3 deletions(-)

diff --git a/src/spec0/releasefilters.py b/src/spec0/releasefilters.py
index 8ba4181..30d8fc8 100644
--- a/src/spec0/releasefilters.py
+++ b/src/spec0/releasefilters.py
@@ -5,7 +5,7 @@
 from packaging.specifiers import SpecifierSet
 from packaging.version import Version
 
-from .releasesource import Release
+from .releasesource import Release, NoReleaseFound
 from .utils.dates import next_quarter, quarter_to_date, shift_date_by_months
 
 import logging
@@ -68,8 +68,8 @@ def _get_minimum_supported(self, package: str, releases: Iterable[Release]):
 
         try:
             max_minor_release = max(oldest_minor_release)
-        except ValueError:  # no releases found
-            raise RuntimeError(f"No releases found for package '{package}'")
+        except ValueError:  # no releases found; should be caught by source
+            raise NoReleaseFound(f"No releases found for package '{package}'")
         # always support at least the most recent minor release
         supported = {max_minor_release: oldest_minor_release[max_minor_release]}
 
diff --git a/src/spec0/releasesource.py b/src/spec0/releasesource.py
index 6a7c439..2b74510 100644
--- a/src/spec0/releasesource.py
+++ b/src/spec0/releasesource.py
@@ -203,6 +203,8 @@ def _get_releases_owner_repo(self, owner_repo: str):
         has_next_page = True
         after_cursor = None
 
+        found_package = False
+
         while has_next_page:
             variables = {
                 "owner": owner,
@@ -234,10 +236,16 @@ def _get_releases_owner_repo(self, owner_repo: str):
                     datestr.replace("Z", "+00:00")
                 )
                 yield Release(version, release_date)
+                found_package = True
 
             has_next_page = releases_data["pageInfo"]["hasNextPage"]
             after_cursor = releases_data["pageInfo"]["endCursor"]
 
+        if not found_package:
+            raise NoReleaseFound(
+                f"No releases found for GitHub repository '{owner_repo}'"
+            )
+
 
 class CondaReleaseSource(ReleaseSource):
     """
diff --git a/tests/test_releasefilters.py b/tests/test_releasefilters.py
index 6839b53..3cf7f00 100644
--- a/tests/test_releasefilters.py
+++ b/tests/test_releasefilters.py
@@ -4,6 +4,7 @@
 from unittest.mock import patch
 
 from spec0.releasefilters import *
+from spec0.releasesource import NoReleaseFound
 
 read_datetime = datetime.datetime
 
@@ -104,6 +105,15 @@ def test_filter(self, releases):
                 )
                 assert key in supported
 
+    def test_filter_empty_releases(self):
+        package_name = "nonexistent-package"
+        spec_strict = SPEC0StrictDate()
+
+        with pytest.raises(
+            NoReleaseFound, match=f"No releases found for package '{package_name}'"
+        ):
+            spec_strict.filter(package_name, [])
+
     @pytest.mark.parametrize("python_override", [True, False])
     @pytest.mark.parametrize("package", ["foo", "python"])
     def test_drop_date(self, python_override, package):
@@ -141,6 +151,15 @@ def test_filter(self, releases):
                 )
                 assert key in supported
 
+    def test_filter_empty_releases(self):
+        package_name = "nonexistent-package"
+        spec_quarter = SPEC0Quarter()
+
+        with pytest.raises(
+            NoReleaseFound, match=f"No releases found for package '{package_name}'"
+        ):
+            spec_quarter.filter(package_name, [])
+
     @pytest.mark.parametrize("python_override", [True, False])
     @pytest.mark.parametrize("package", ["foo", "python"])
     def test_drop_date(self, python_override, package):
diff --git a/tests/test_releasesource.py b/tests/test_releasesource.py
index 8c8d66d..b99f1c5 100644
--- a/tests/test_releasesource.py
+++ b/tests/test_releasesource.py
@@ -475,6 +475,37 @@ def test_get_releases_not_found(self, package):
         with pytest.raises(NoReleaseFound, match=expected_message):
             list(source._get_releases(package))
 
+    @responses.activate
+    def test_get_releases_no_releases_found(self):
+        """Test that a NoReleaseFound exception is raised when a GitHub repository exists but has no releases."""
+        url = "https://api.github.com/graphql"
+        # Mock an empty response with no releases
+        empty_response = {
+            "data": {
+                "repository": {
+                    "refs": {
+                        "pageInfo": {"endCursor": None, "hasNextPage": False},
+                        "nodes": [],
+                    }
+                }
+            }
+        }
+        responses.add(
+            responses.POST,
+            url,
+            json=empty_response,
+            status=200,
+        )
+
+        token = "FAKE_TOKEN"
+        source = GitHubReleaseSource(token)
+
+        expected_message = (
+            "No releases found for GitHub repository 'octocat/empty-repo'"
+        )
+        with pytest.raises(NoReleaseFound, match=expected_message):
+            list(source._get_releases_owner_repo("octocat/empty-repo"))
+
 
 def make_release(version: str, date_str: str):
     dt = datetime.datetime.fromisoformat(date_str).replace(tzinfo=datetime.timezone.utc)

From 4d1d04e1ee38b6942a9704746ab7ca29f27893d9 Mon Sep 17 00:00:00 2001
From: "David W.H. Swenson" <david.swenson@omsf.io>
Date: Wed, 9 Apr 2025 19:10:05 -0500
Subject: [PATCH 14/15] I guess I still have Python tricks to learn!

---
 src/spec0/releasesource.py | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/src/spec0/releasesource.py b/src/spec0/releasesource.py
index 2b74510..658ee73 100644
--- a/src/spec0/releasesource.py
+++ b/src/spec0/releasesource.py
@@ -6,7 +6,6 @@
 import warnings
 from packaging.version import Version, InvalidVersion
 import importlib.resources
-import collections
 
 from typing import Generator
 
@@ -112,7 +111,7 @@ def __init__(self, github_token: str):
 
     def is_github_package(self, package: str) -> bool:
         """Check if the package is a GitHub package."""
-        if collections.Counter(package).get("/") == 1:
+        if package.count("/") == 1:
             return True
         elif package in self.canonical_sources:
             return True
@@ -120,7 +119,7 @@ def is_github_package(self, package: str) -> bool:
             return False
 
     def _get_releases(self, package: str):
-        if collections.Counter(package).get("/") == 1:
+        if package.count("/") == 1:
             owner_repo = package
         elif package in self.canonical_sources:
             owner_repo = self.canonical_sources[package]

From fa1a7bda1a7a9633a5bacaa6f614fe9e561cb50c Mon Sep 17 00:00:00 2001
From: "David W.H. Swenson" <dwhs@hyperblazer.net>
Date: Wed, 9 Apr 2025 19:11:29 -0500
Subject: [PATCH 15/15] `self.github_token` -> `token`

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
---
 src/spec0/releasesource.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/spec0/releasesource.py b/src/spec0/releasesource.py
index 658ee73..2bc3bce 100644
--- a/src/spec0/releasesource.py
+++ b/src/spec0/releasesource.py
@@ -195,7 +195,7 @@ def _get_releases_owner_repo(self, owner_repo: str):
 
         url = "https://api.github.com/graphql"
         headers = {
-            "Authorization": f"Bearer {self.github_token}",
+            "Authorization": f"Bearer {token}",
             "Accept": "application/vnd.github.v3+json",
         }