feat: from-sdist for overrides

docs/overrides.md

@@ -127,6 +127,11 @@ and `metadata_editable`. Takes a regex.
 Note that you can build directly to wheel; you don't have to go through an
 SDist.
 
+### `from-sdist` (bool)
+
+This will be true if the `PKG-INFO` file exists, that is, if this is coming
+from an SDist. Takes a bool.
+
 ## Any matching condition
 
 If you use `if.any` instead of `if`, then the override is true if any one of the

src/scikit_build_core/resources/scikit-build.schema.json

@@ -624,6 +624,10 @@
           "type": "string",
           "description": "The state of the build, one of `sdist`, `wheel`, `editable`, `metadata_wheel`, and `metadata_editable`. Takes a regex."
         },
+        "from-sdist": {
+          "type": "boolean",
+          "description": "Whether the build is from an sdist."
+        },
         "env": {
           "type": "object",
           "patternProperties": {

src/scikit_build_core/settings/skbuild_read_settings.py

@@ -71,6 +71,7 @@ def override_match(
     current_state: Literal[
         "sdist", "wheel", "editable", "metadata_wheel", "metadata_editable"
     ],
+    has_dist_info: bool,
     python_version: str | None = None,
     implementation_name: str | None = None,
     implementation_version: str | None = None,
@@ -79,8 +80,14 @@ def override_match(
     platform_node: str | None = None,
     env: dict[str, str] | None = None,
     state: str | None = None,
+    from_sdist: bool | None = None,
 ) -> bool:
+    # This makes a matches list. A match is a string; if it's an empty string,
+    # then it did not match. If it's not empty, it did match, and the string
+    # will be printed in the logs - it's the match reason. If match_all is True,
+    # then all must match, otherwise any match will count.
     matches = []
+
     if current_env is None:
         current_env = os.environ
 
@@ -124,6 +131,12 @@ def override_match(
         match_msg = regex_match(current_state, state)
         matches.append(match_msg)
 
+    if from_sdist is not None:
+        if has_dist_info:
+            matches.append("from sdist due to PKG-INFO" if from_sdist else "")
+        else:
+            matches.append("" if from_sdist else "not from sdist, no PKG-INFO")
+
     if env:
         for key, value in env.items():
             if isinstance(value, bool):
@@ -264,8 +277,10 @@ def process_overides(
     env: Mapping[str, str] | None = None,
 ) -> None:
     """
-    Process overrides into the main dictionary if they match. Modifies the input dictionary.
+    Process overrides into the main dictionary if they match. Modifies the input
+    dictionary. Must be run from the package directory.
     """
+    has_dist_info = Path("PKG-INFO").is_file()
 
     for override in tool_skb.pop("overrides", []):
         matched = True
@@ -280,7 +295,11 @@ def process_overides(
             any_override = if_override.pop("any")
             select = {k.replace("-", "_"): v for k, v in any_override.items()}
             matched = override_match(
-                match_all=False, current_env=env, current_state=state, **select
+                match_all=False,
+                current_env=env,
+                current_state=state,
+                has_dist_info=has_dist_info,
+                **select,
             )
 
         inherit_override = override.pop("inherit", {})
@@ -291,7 +310,11 @@ def process_overides(
         select = {k.replace("-", "_"): v for k, v in if_override.items()}
         if select:
             matched = matched and override_match(
-                match_all=True, current_env=env, current_state=state, **select
+                match_all=True,
+                current_env=env,
+                current_state=state,
+                has_dist_info=has_dist_info,
+                **select,
             )
         if matched:
             for key, value in override.items():

src/scikit_build_core/settings/skbuild_schema.py

@@ -116,6 +116,10 @@ def generate_skbuild_schema(tool_name: str = "scikit-build") -> dict[str, Any]:
                 "type": "string",
                 "description": "The state of the build, one of `sdist`, `wheel`, `editable`, `metadata_wheel`, and `metadata_editable`. Takes a regex.",
             },
+            "from-sdist": {
+                "type": "boolean",
+                "description": "Whether the build is from an sdist.",
+            },
             "env": {
                 "type": "object",
                 "patternProperties": {

tests/test_settings_overrides.py

@@ -490,3 +490,43 @@ def test_skbuild_overrides_inherit(inherit: str, tmp_path: Path):
         assert settings.wheel.exclude == ["xx", "yy", "x", "y"]
         assert settings.install.components == ["c", "d", "a", "b"]
         assert settings.cmake.define == {"a": "A", "b": "B", "c": "C"}
+
+
+@pytest.mark.parametrize("from_sdist", [True, False])
+def test_skbuild_overrides_from_sdist(
+    tmp_path: Path, monkeypatch: pytest.MonkeyPatch, from_sdist: bool
+):
+    pyproject_toml = (
+        tmp_path / ("from_sdist" if from_sdist else "not_from_sdist") / "pyproject.toml"
+    )
+    pyproject_toml.parent.mkdir(exist_ok=True)
+    pyproject_toml.write_text(
+        dedent(
+            """\
+            [tool.scikit-build]
+            cmake.version = ">=3.15"
+            wheel.cmake = false
+            sdist.cmake = false
+
+            [[tool.scikit-build.overrides]]
+            if.from-sdist = false
+            wheel.cmake = true
+
+            [[tool.scikit-build.overrides]]
+            if.from-sdist = true
+            sdist.cmake = true
+            """
+        ),
+        encoding="utf-8",
+    )
+
+    if from_sdist:
+        pyproject_toml.parent.joinpath("PKG-INFO").touch(exist_ok=True)
+
+    monkeypatch.chdir(pyproject_toml.parent)
+
+    settings_reader = SettingsReader.from_file(pyproject_toml, state="wheel")
+    settings = settings_reader.settings
+
+    assert settings.wheel.cmake != from_sdist
+    assert settings.sdist.cmake == from_sdist