1 files changed, 105 insertions, 0 deletions
diff --git a/src/setuptools_scm/_integration/setuptools.py b/src/setuptools_scm/_integration/setuptools.py
index 6e04148..94981d7 100644
--- a/src/setuptools_scm/_integration/setuptools.py
+++ b/src/setuptools_scm/_integration/setuptools.py
@@ -1,6 +1,17 @@
 from __future__ import annotations
 
+import logging
 import os
+import warnings
+from typing import Any
+from typing import Callable
+
+import setuptools
+
+from .. import _config
+from .._version_cls import _validate_version_cls
+
+log = logging.getLogger(__name__)
 
 
 def read_dist_name_from_setup_cfg(
@@ -13,3 +24,97 @@ def read_dist_name_from_setup_cfg(
     parser.read([input], encoding="utf-8")
     dist_name = parser.get("metadata", "name", fallback=None)
     return dist_name
+
+
+def _warn_on_old_setuptools(_version: str = setuptools.__version__) -> None:
+    if int(_version.split(".")[0]) < 61:
+        warnings.warn(
+            RuntimeWarning(
+                f"""
+ERROR: setuptools=={_version} is used in combination with setuptools_scm>=8.x
+
+Your build configuration is incomplete and previously worked by accident!
+setuptools_scm requires setuptools>=61
+
+Suggested workaround if applicable:
+ - migrating from the deprecated setup_requires mechanism to pep517/518
+   and using a pyproject.toml to declare build dependencies
+   which are reliably pre-installed before running the build tools
+"""
+            )
+        )
+
+
+def _assign_version(
+    dist: setuptools.Distribution, config: _config.Configuration
+) -> None:
+    from .. import _get_version, _version_missing
+
+    maybe_version = _get_version(config)
+
+    if maybe_version is None:
+        _version_missing(config)
+    else:
+        assert dist.metadata.version is None
+        dist.metadata.version = maybe_version
+
+
+_warn_on_old_setuptools()
+
+
+def version_keyword(
+    dist: setuptools.Distribution,
+    keyword: str,
+    value: bool | dict[str, Any] | Callable[[], dict[str, Any]],
+) -> None:
+    if not value:
+        return
+    elif value is True:
+        value = {}
+    elif callable(value):
+        value = value()
+    assert (
+        "dist_name" not in value
+    ), "dist_name may not be specified in the setup keyword "
+    dist_name: str | None = dist.metadata.name
+    if dist.metadata.version is not None:
+        warnings.warn(f"version of {dist_name} already set")
+        return
+    log.debug(
+        "version keyword %r",
+        vars(dist.metadata),
+    )
+    log.debug("dist %s %s", id(dist), id(dist.metadata))
+
+    if dist_name is None:
+        dist_name = read_dist_name_from_setup_cfg()
+    version_cls = value.pop("version_cls", None)
+    normalize = value.pop("normalize", True)
+    final_version = _validate_version_cls(version_cls, normalize)
+    config = _config.Configuration(
+        dist_name=dist_name, version_cls=final_version, **value
+    )
+    _assign_version(dist, config)
+
+
+def infer_version(dist: setuptools.Distribution) -> None:
+    log.debug(
+        "finalize hook %r",
+        vars(dist.metadata),
+    )
+    log.debug("dist %s %s", id(dist), id(dist.metadata))
+    if dist.metadata.version is not None:
+        return  # metadata already added by hook
+    dist_name = dist.metadata.name
+    if dist_name is None:
+        dist_name = read_dist_name_from_setup_cfg()
+    if not os.path.isfile("pyproject.toml"):
+        return
+    if dist_name == "setuptools_scm":
+        return
+    try:
+        config = _config.Configuration.from_file(dist_name=dist_name)
+    except LookupError as e:
+        log.exception(e)
+    else:
+        _assign_version(dist, config)