Create build/bin/sage-build-env-config and call it from build/make/deps; add sage --buildsh

[mkoeppe]

This is part of #21707 - "Split sage-env into 5".

We set up a new configure-generated, to-be-sourced shell script build/bin/sage-build-env-config to which we move environment variable settings from src/bin/sage-env[-config] that are only needed for:

1. Sage-the-distribution while building spkgs,
2. Sage-the-distribution for building sagelib.

The new script is used in addition to src/bin/sage-env in these two contexts.

We add a command sage --buildsh, like sage --sh but using the larger environment.

---

Follow-up:

• build/make/install contains more environment settings that should be reviewed for moving to sage-build-env-config

Depends on #29233

CC: @dimpase @embray @jdemeyer @kiwifb @isuruf

Component: build

Author: Matthias Koeppe

Branch/Commit: 2ab9b09

Reviewer: Dima Pasechnik, Volker Braun

Issue created by migration from https://trac.sagemath.org/ticket/29052

[mkoeppe]

Description changed:

--- 
+++ 
@@ -5,7 +5,7 @@
 1. Sage-the-distribution while building spkgs,
 2. Sage-the-distribution for building sagelib.
 
-The new script sources `src/bin/sage-env`.
+The new script is used in addition to `src/bin/sage-env` in these two contexts.
 
 We add a command `sage --buildsh`, like `sage --sh` but using the larger environment.
 

[mkoeppe]

Description changed:

--- 
+++ 
@@ -1,6 +1,6 @@
 This is part of #21707 - "Split `sage-env` into 5". 
 
-We set up a new `configure`-generated, to-be-`source`d shell script `build/bin/sage-build-env` to which we move environment variable settings from `src/bin/sage-env[-config]` that are only needed for:
+We set up a new `configure`-generated, to-be-`source`d shell script `build/bin/sage-build-env-config` to which we move environment variable settings from `src/bin/sage-env[-config]` that are only needed for:
 
 1. Sage-the-distribution while building spkgs,
 2. Sage-the-distribution for building sagelib.

[mkoeppe]

Branch: u/mkoeppe/create_build_bin_sage_build_env_and_call_it_from_build_make_deps__add_sage___buildsh

[sagetrac-git]

Commit: e3e5a08

[sagetrac-git]

Branch pushed to git repo; I updated commit sha1. New commits:

e3e5a08

build/make/deps, build/make.Makefile.in: Source build/bin/sage-build-env-config for building sagelib and for script packages

[mkoeppe]

comment:6

Updated the branch that was on #21707.

[mkoeppe]

Description changed:

--- 
+++ 
@@ -9,3 +9,7 @@
 
 We add a command `sage --buildsh`, like `sage --sh` but using the larger environment.
 
+---
+
+Follow-up: 
+- `build/make/install` contains more environment settings that should be reviewed for moving to `sage-build-env-config`

[jhpalmieri]

comment:8

You need to document sage --buildsh: at the top of src/bin/sage, in src/doc/en/reference/repl/options.rst, maybe in src/doc/en/installation/source.rst, maybe in the developer's guide.

[mkoeppe]

comment:9

Thanks! Will do.

[sagetrac-git]

Changed commit from e3e5a08 to 4a96e26

[sagetrac-git]

Branch pushed to git repo; I updated commit sha1. New commits:

7ea77bb	Document 'sage -buildsh' in the output of 'sage -advanced'
4a96e26	src/doc/en/reference/repl/options.rst: Document sage --buildsh

[sagetrac-git]

Changed commit from 4a96e26 to 80c6bfd

[sagetrac-git]

Branch pushed to git repo; I updated commit sha1. New commits:

80c6bfd

Merge tag '9.1.beta1' into t/29052/create_build_bin_sage_build_env_and_call_it_from_build_make_deps__add_sage___buildsh

[mkoeppe]

comment:12

Merged, ready for review

[sagetrac-git]

Changed commit from 80c6bfd to ecb6a8b