gh-37030: Small update to Developer Guide section on portability testing
    
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Split out from #36954 for easier review.

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URL: #37030
Reported by: Matthias Köppe
Reviewer(s): Kwankyu Lee

Author: Release Manager

src/doc/en/developer/portability_testing.rst

@@ -9,7 +9,7 @@ Testing on Multiple Platforms
 =============================
 
 Sage is intended to build and run on a variety of platforms,
-including all major Linux distributions, as well as MacOS, and
+including all major Linux distributions, as well as macOS, and
 Windows (with WSL).
 
 There is considerable variation among these platforms.
@@ -128,9 +128,9 @@ Typical Docker images provide minimal installations of packages only::
 
 As you can see above, the image ``ubuntu:latest`` has neither a Python nor
 a GCC installed, which are among the build prerequisites of Sage.  We
-need to install them using the distribution's package manager first.
+need to install them using the Linux distribution's package manager first.
 
-Sage facilitates testing various distributions on Docker as follows.
+Sage facilitates testing various Linux distributions on Docker as follows.
 
 Discovering the system's package system
 ---------------------------------------
@@ -142,7 +142,7 @@ Discovering the system's package system
 
 Let's install gcc, hoping that the Ubuntu package providing it is
 simply named ``gcc``.  If we forgot what the package manager on
-Debian-derived distributions is called, we can ask Sage for a
+Debian-derived Linux distributions is called, we can ask Sage for a
 reminder::
 
   root@39d693b2a75d:/sage# build/bin/sage-print-system-package-command debian install gcc
@@ -190,7 +190,8 @@ example, the file ``build/pkgs/_prereq/distros/debian.txt`` contains the followi
 From this information, we know that we can use the following command
 on our container to install the necessary build prerequisites::
 
-  root@39d693b2a75d:/sage# apt-get install binutils make m4 perl python3 tar bc gcc g++ ca-certificates
+  root@39d693b2a75d:/sage# apt-get install binutils make m4 perl python3 \
+                                           tar bc gcc g++ ca-certificates
   Reading package lists... Done
   Building dependency tree
   Reading state information... Done
@@ -208,7 +209,8 @@ Now we can start the build::
   root@39d693b2a75d:/sage# ./configure
   checking for a BSD-compatible install... /usr/bin/install -c
   checking for root user... yes
-  configure: error: You cannot build Sage as root, switch to an unprivileged user.  (If building in a container, use --enable-build-as-root.)
+  configure: error: You cannot build Sage as root, switch to an unprivileged user.
+  (If building in a container, use --enable-build-as-root.)
 
 Let's just follow this helpful hint::
 
@@ -225,14 +227,16 @@ Using Sage's database of equivalent distribution packages
 At the end of the ``./configure`` run, Sage issued a message like the
 following::
 
-  configure: notice: the following SPKGs did not find equivalent system packages: arb boost_cropped bzip2 ... zeromq zlib
+  configure: notice: the following SPKGs did not find equivalent system packages:
+                     arb boost_cropped bzip2 ... zeromq zlib
   checking for the package system in use... debian
-  configure: hint: installing the following system packages is recommended and may avoid building some of the above SPKGs from source:
+  configure: hint: installing the following system packages is recommended and
+                   may avoid building some of the above SPKGs from source:
   configure:   $ sudo apt-get install libflint-arb-dev ... libzmq3-dev libz-dev
   configure: After installation, re-run configure using:
   configure:   $ make reconfigure
 
-This information comes from Sage's database of equivalent distribution
+This information comes from Sage's database of equivalent system
 packages.  For example::
 
   root@39d693b2a75d:/sage# ls build/pkgs/arb/distros/
@@ -268,9 +272,9 @@ corresponding to its current state::
 
   root@39d693b2a75d:/sage# ^D
   [mkoeppe@sage worktree-ubuntu-latest]$ docker ps -a | head -n3
-  CONTAINER ID        IMAGE                   COMMAND                   CREATED             STATUS
-  39d693b2a75d        ubuntu:latest           "/bin/bash"               8 minutes ago       Exited (0) 6 seconds ago
-  9f3398da43c2        ubuntu:latest           "/bin/bash"               8 minutes ago       Exited (0) 8 minutes ago
+  CONTAINER ID   IMAGE           COMMAND       CREATED         STATUS
+  39d693b2a75d   ubuntu:latest   "/bin/bash"   8 minutes ago   Exited (0) 6 seconds ago
+  9f3398da43c2   ubuntu:latest   "/bin/bash"   8 minutes ago   Exited (0) 8 minutes ago
   [mkoeppe@sage worktree-ubuntu-latest]$ docker commit 39d693b2a75d ubuntu-latest-minimal-17
   sha256:4151c5ca4476660f6181cdb13923da8fe44082222b984c377fb4fd6cc05415c1
 
@@ -506,7 +510,8 @@ might not work on all platforms, ``surf``, which was marked as
   ...
   Makefile:31: recipe for target 'surf' failed
   make: *** [surf] Error 1
-  The command '/bin/sh -c make SAGE_SPKG="sage-spkg -y -o" ${USE_MAKEFLAGS} ${TARGETS_PRE}' returned a non-zero code: 2
+  The command '/bin/sh -c make SAGE_SPKG="sage-spkg -y -o" ${USE_MAKEFLAGS} ${TARGETS_PRE}'
+  returned a non-zero code: 2
 
 Note that no image id is shown at the end; the build failed, and no
 image is created.  However, the container in which the last step of
@@ -688,11 +693,11 @@ the one just after running the ``configure`` script (``configured``)::
 
 Let's verify that the images are available::
 
-  (base) egret:~/s/sage/sage-rebasing/worktree-algebraic-2018-spring (mkoeppe *$%>)$ docker images | head
-  REPOSITORY                                                TAG                               IMAGE ID
-  sage-centos-8-standard-with-targets                9.1.beta9-435-g861ba33bbc-dirty   7ecfa86fceab
-  sage-centos-8-standard-configured                  9.1.beta9-435-g861ba33bbc-dirty   4314929e2b4c
-  sage-centos-8-standard-with-system-packages        9.1.beta9-435-g861ba33bbc-dirty   4bb14c3d5646
+  [mkoeppe@sage sage]$ docker images | head
+  REPOSITORY                                    TAG                               IMAGE ID
+  sage-centos-8-standard-with-targets           9.1.beta9-435-g861ba33bbc-dirty   7ecfa86fceab
+  sage-centos-8-standard-configured             9.1.beta9-435-g861ba33bbc-dirty   4314929e2b4c
+  sage-centos-8-standard-with-system-packages   9.1.beta9-435-g861ba33bbc-dirty   4bb14c3d5646
   ...
 
 
@@ -1204,13 +1209,13 @@ Using our pre-built Docker images for development in VS Code
 
 `VS Code <https://code.visualstudio.com/>`_ is very
 convenient for developing with Docker containers thanks to the `Visual
-Studio Code Remote - Containers
-<https://code.visualstudio.com/docs/remote/containers>`_ extension.
+Studio Code Dev Containers
+<https://code.visualstudio.com/docs/devcontainers/containers>`_ extension.
 
 If the extension is not already installed, then in VS Code, click the
 "Extension" icon on the left (or press :kbd:`Ctrl` + :kbd:`Shift` + :kbd:`X`;
 on macOS, :kbd:`Command` + :kbd:`Shift` + :kbd:`X`) to open a list of
-extensions. Search for "Remote - Containers" and install it.
+extensions. Search for "Dev Containers" and install it.
 
 The extension needs a ``devcontainer.json`` configuration file to work. Sage
 provides sample ``devcontainer.json`` configuration files
@@ -1220,11 +1225,11 @@ purpose.
 
 If you open the sage folder in VS Code, it may prompt you whether you would like to open the current
 directory in the dev container (yes).  If it does not, use the command palette
-(:kbd:`Ctrl` + :kbd:`Shift` + :kbd:`P`), enter the command "Remote-Containers:
+(:kbd:`Ctrl` + :kbd:`Shift` + :kbd:`P`), enter the command "Dev Containers:
 Reopen Folder in Container" , and hit :kbd:`Enter`.
 
 If the above ``code .`` command does not work, start VS Code as a regular
-application, then in the command palette of VS Code, enter "Remote-Containers:
+application, then in the command palette of VS Code, enter "Dev Containers:
 Open Folder in Container", and hit :kbd:`Enter`, and choose the directory
 ``$SAGE_ROOT`` of your local Sage repository.
 
@@ -1271,7 +1276,7 @@ in a terminal, `open a new terminal in VS Code
    ``configure`` script.
 
 You can edit a copy of the configuration file to change to a different platform, another
-version, or build stage.  After editing the configuration file, run "Remote-Containers: Rebuild Container" from the command
+version, or build stage.  After editing the configuration file, run "Dev Containers: Rebuild Container" from the command
 palette. See the `VS Code devcontainer.json reference
 <https://code.visualstudio.com/docs/remote/devcontainerjson-reference>`_
 and the `GitHub introduction to dev containers