GH-107956: install a static description file

Signed-off-by: Filipe Laíns <[email protected]>

Author: FFY00

.gitignore

@@ -124,6 +124,7 @@ Tools/unicode/data/
 /config.status.lineno
 # hendrikmuhs/ccache-action@v1
 /.ccache
+/install-details.toml
 /platform
 /profile-clean-stamp
 /profile-run-stamp

Makefile.pre.in

@@ -615,7 +615,7 @@ all:		@DEF_MAKE_ALL_RULE@
 
 .PHONY: build_all
 build_all:	check-clean-src $(BUILDPYTHON) platform sharedmods \
-		gdbhooks Programs/_testembed scripts checksharedmods rundsymutil
+		gdbhooks Programs/_testembed scripts checksharedmods rundsymutil install-details.toml
 
 .PHONY: build_wasm
 build_wasm: check-clean-src $(BUILDPYTHON) platform sharedmods \
@@ -790,6 +790,9 @@ $(BUILDPYTHON):	Programs/python.o $(LINK_PYTHON_DEPS)
 platform: $(PYTHON_FOR_BUILD_DEPS) pybuilddir.txt
 	$(RUNSHARED) $(PYTHON_FOR_BUILD) -c 'import sys ; from sysconfig import get_platform ; print("%s-%d.%d" % (get_platform(), *sys.version_info[:2]))' >platform
 
+install-details.toml: $(PYTHON_FOR_BUILD_DEPS) pybuilddir.txt $(srcdir)/Tools/build/generate_install_details_file.py
+	$(RUNSHARED) $(PYTHON_FOR_BUILD) $(srcdir)/Tools/build/generate_install_details_file.py ./install-details.toml
+
 # Create build directory and generate the sysconfig build-time data there.
 # pybuilddir.txt contains the name of the build dir and is used for
 # sys.path fixup -- see Modules/getpath.c.
@@ -1948,7 +1951,7 @@ altinstall: commoninstall
 .PHONY: commoninstall
 commoninstall:  check-clean-src @FRAMEWORKALTINSTALLFIRST@ \
 		altbininstall libinstall inclinstall libainstall \
-		sharedinstall altmaninstall @FRAMEWORKALTINSTALLLAST@
+		sharedinstall altmaninstall descfileinstall @FRAMEWORKALTINSTALLLAST@
 
 # Install shared libraries enabled by Setup
 DESTDIRS=	$(exec_prefix) $(LIBDIR) $(BINLIBDEST) $(DESTSHARED)
@@ -2552,6 +2555,11 @@ frameworkaltinstallunixtools:
 frameworkinstallextras:
 	cd Mac && $(MAKE) installextras DESTDIR="$(DESTDIR)"
 
+# Install the
+.PHONY: descfileinstall
+descfileinstall:
+	$(INSTALL) -d -m $(FILEMODE) ./install-details.toml $(DESTDIR)$(LIBDEST)/install-details.toml
+
 # Build the toplevel Makefile
 Makefile.pre: $(srcdir)/Makefile.pre.in config.status
 	CONFIG_FILES=Makefile.pre CONFIG_HEADERS= ./config.status
@@ -2652,6 +2660,7 @@ clean-retain-profile: pycremoval
 	find build -name '*.py' -exec rm -f {} ';' || true
 	find build -name '*.py[co]' -exec rm -f {} ';' || true
 	-rm -f pybuilddir.txt
+	-rm -f install-details.toml
 	-rm -f _bootstrap_python
 	-rm -f python.html python*.js python.data python*.symbols python*.map
 	-rm -f $(WASM_STDLIB)

Tools/build/generate_install_details_file.py

@@ -0,0 +1,65 @@
+import argparse
+import io
+import os
+import sys
+import sysconfig
+import tomllib
+
+from typing import Any, Callable
+
+
+ConfigItem = str | int | list[str | int]
+ConfigData = dict[str, dict[str, ConfigItem]]
+
+
+def generic_info() -> ConfigData:
+    return {
+        'python': {
+            'version': sys.version.split(' ')[0],
+            'version_parts': {
+                field: getattr(sys.version_info, field)
+                for field in ('major', 'minor', 'micro', 'releaselevel', 'serial')
+            },
+            'executable': os.path.join(
+                sysconfig.get_path('scripts'),
+                os.path.basename(sys.executable),
+            ),
+            'stdlib': sysconfig.get_path('stdlib'),
+        },
+    }
+
+
+def toml_dump(fd: io.TextIOBase, data: ConfigData) -> None:
+    """**Very** basic TOML writer. It only implements what is necessary for this use-case."""
+    def toml_repr(obj: object) -> str:
+        if isinstance(obj, dict):
+            return '{ ' + ', '.join(f'{k} = {toml_repr(v)}' for k, v in obj.items()) + ' }'
+        else:
+            return repr(obj)
+
+    for section, entries in data.items():
+        print(f'[{section}]', file=fd)
+        for name, value in entries.items():
+            print(f'{name} = {toml_repr(value)}', file=fd)
+        fd.write('\n')
+
+
+def main() -> None:
+    parser = argparse.ArgumentParser()
+    parser.add_argument('output_path', metavar='FILE')
+
+    args = parser.parse_args()
+
+    config = generic_info()
+
+    # write TOML with our very basic writer
+    with open(args.output_path, 'w') as f:
+        toml_dump(f, config)
+
+    # try to load the data as a sanity check to verify our writer outputed, at least, valid TOML
+    with open(args.output_path, 'rb') as f:
+        parsed = tomllib.load(f)
+
+
+if __name__ == '__main__':
+    main()