Trac #29850: Install sage-env-config as part of sage_conf

As a follow-up to #21559 and #30128, we reassign `sage-env-config` from
the package `sagelib` to the package `sage_conf`.

(After #22731, `sage-env-config` is no longer required by the `sage`
script.)

(This is preparation for allowing installation of sagelib for example in
a conda environment without having to run ./configure first - see
#28745, #30845.)

------

Part of Meta-ticket #21707: Split sage-env into 5 to clean up sage
configuration

URL: https://trac.sagemath.org/29850
Reported by: mkoeppe
Ticket author(s): Matthias Koeppe
Reviewer(s): Dima Pasechnik

build/pkgs/sage_conf/dependencies

@@ -1 +1 @@
-$(PYTHON) ../pkgs/sage_conf/src/sage_conf.py ../pkgs/sage_conf/src/setup.cfg | $(PYTHON_TOOLCHAIN)
+$(PYTHON) ../pkgs/sage_conf/src/sage_conf.py ../pkgs/sage_conf/src/setup.cfg ../pkgs/sage_conf/src/bin/sage-env-config | $(PYTHON_TOOLCHAIN)

build/pkgs/sage_conf/spkg-install

@@ -9,4 +9,8 @@ if [ $? -ne 0 ]; then
     echo >&2 "Is $SAGE_ROOT the correct SAGE_ROOT?"
     exit 1
 fi
-cd src && sdh_pip_install .
+cd src
+# Need to build a wheel manually because pip does not
+# follow symlinks.
+sdh_setup_bdist_wheel
+sdh_store_and_pip_install_wheel .

build/pkgs/sage_conf/spkg-src

@@ -0,0 +1,21 @@
+#!/usr/bin/env bash
+#
+# Script to prepare an sdist tarball for sage_conf
+# This script is not used during build.
+#
+# HOW TO MAKE THE TARBALL:
+# ./sage --sh build/pkgs/sage_conf/spkg-src
+
+if [ -z "$SAGE_ROOT" ] ; then
+    echo >&2 "Error - SAGE_ROOT undefined ... exiting"
+    echo >&2 "Maybe run 'sage -sh'?"
+    exit 1
+fi
+
+# Exit on failure
+set -e
+
+cd build/pkgs/sage_conf
+
+cd src
+sage-python23 -u setup.py --no-user-cfg sdist --dist-dir "$SAGE_DISTFILES"

build/pkgs/sage_conf/src/MANIFEST.in

@@ -0,0 +1 @@
+include bin/sage-env-config

build/pkgs/sage_conf/src/bin/sage-env-config

@@ -0,0 +1 @@
+../../../../../src/bin/sage-env-config

build/pkgs/sage_conf/src/setup.cfg.in

@@ -14,6 +14,9 @@ url = https://www.sagemath.org
 py_modules =
     sage_conf
 
+scripts =
+    bin/sage-env-config
+
 [options.entry_points]
 console_scripts =
     sage-config = sage_conf:_main

build/pkgs/sagelib/src/setup.py

@@ -148,7 +148,7 @@
                  ## Uncategorized scripts in alphabetical order
                  'bin/math-readline',
                  'bin/sage-env',
-                 'bin/sage-env-config',
+                 # sage-env-config -- installed by sage_conf
                  # sage-env-config.in -- not to be installed',
                  'bin/sage-gdb-commands',
                  'bin/sage-grep',

src/setup.py

@@ -146,8 +146,8 @@
                  ## Uncategorized scripts in alphabetical order
                  'bin/math-readline',
                  'bin/sage-env',
-                 'bin/sage-env-config',
-                 # sage-env-config.in -- not to be installed',
+                 # sage-env-config -- installed by sage_conf
+                 # sage-env-config.in -- not to be installed
                  'bin/sage-gdb-commands',
                  'bin/sage-grep',
                  'bin/sage-grepdoc',