Rename `nix show-config` to `nix config show`

Part of #7672

My main motivation is to be able to use `nix.checkConfig`[1]. This
doesn't work with Lix currently since the module uses `nix show-config`
if the Nix version is <2.20pre and `nix config show` otherwise. I think
this is the only instance where nixpkgs checks for which Nix commands
exist that affects us now, so I figured we could just perform the rename
here as well[2] and still provide the current version number[3].

I don't have a strong opinion on whether to deprecate `nix show-config`,
the warning is added there automatically.

(cherry picked from commit f300e11b056dea414d7d77bbc6e5a7dc5d9ddd41)

[1] https://nixos.org/manual/nixos/stable/options.html#opt-nix.checkConfig
[2] I should add that I don't use the "official" ways of installing Lix
    because using the flake directly and callPackaging it seemed to fit
    better into my workflow: I already have a little mess to make
    sure Hydra from the flake uses the correct pkgs.nix and I didn't
    want to complicate it further while keeping a single package-set I
    can build in CI. Don't get me wrong, I think such a module for a
    quick-start is very important, just giving context on why I bother
    in the first place :)
[3] When we go public, I think it's worth considering to add support in
    nixpkgs itself for Lix.

Change-Id: I47b4239b05cbeda3c370d2fa56ea768b768768ac

7 files changed, 15 insertions, 4 deletions

diff --git a/doc/manual/local.mk b/doc/manual/local.mk
index 215609f79..50c67b8ae 100644
--- a/doc/manual/local.mk
+++ b/doc/manual/local.mk
@@ -29,7 +29,7 @@ man-pages += $(foreach subcommand, \
 clean-files += $(d)/*.1 $(d)/*.5 $(d)/*.8
 
 # Provide a dummy environment for nix, so that it will not access files outside the macOS sandbox.
-# Set cores to 0 because otherwise nix show-config resolves the cores based on the current machine
+# Set cores to 0 because otherwise nix config show resolves the cores based on the current machine
 dummy-env = env -i \
 	HOME=/dummy \
 	NIX_CONF_DIR=/dummy \
@@ -89,7 +89,7 @@ doc/manual/generated/in/nix.json: $(doc_nix)
 
 doc/manual/generated/in/conf-file.json: $(doc_nix)
 	@mkdir -p doc/manual/generated/in
-	$(trace-gen) $(dummy-env) $(doc_nix) show-config --json --experimental-features nix-command > $@.tmp
+	$(trace-gen) $(dummy-env) $(doc_nix) config show --json --experimental-features nix-command > $@.tmp
 	@mv $@.tmp $@
 
 doc/manual/generated/in/contributing/experimental-feature-descriptions.md: doc/manual/generated/in/xp-features.json $(d)/utils.nix $(d)/generate-xp-features.nix $(doc_nix)
diff --git a/doc/manual/meson.build b/doc/manual/meson.build
index cfb6be36f..e253a9bd8 100644
--- a/doc/manual/meson.build
+++ b/doc/manual/meson.build
@@ -197,6 +197,8 @@ endforeach
 nix3_manpages = [
   'nix3-build',
   'nix3-bundle',
+  'nix3-config',
+  'nix3-config-show',
   'nix3-copy',
   'nix3-daemon',
   'nix3-derivation-add',
@@ -258,7 +260,6 @@ nix3_manpages = [
   'nix3-run',
   'nix3-search',
   'nix3-shell',
-  'nix3-show-config',
   'nix3-store-add-file',
   'nix3-store-add-path',
   'nix3-store-cat',
diff --git a/doc/manual/rl-next/nix-config-show.md b/doc/manual/rl-next/nix-config-show.md
new file mode 100644
index 000000000..1e7545e73
--- /dev/null
+++ b/doc/manual/rl-next/nix-config-show.md
@@ -0,0 +1,7 @@
+---
+synopsis: rename 'nix show-config' to 'nix config show'
+issues: 7672
+prs: 9477
+---
+
+`nix show-config` was renamed to `nix config show` to be more consistent with the rest of the command-line interface.
diff --git a/doc/manual/src/SUMMARY.md b/doc/manual/src/SUMMARY.md
index 7747b9061..2437c0dc5 100644
--- a/doc/manual/src/SUMMARY.md
+++ b/doc/manual/src/SUMMARY.md
@@ -91,6 +91,8 @@
     - [nix](command-ref/new-cli/nix.md)
     - [nix build](command-ref/new-cli/nix3-build.md)
     - [nix bundle](command-ref/new-cli/nix3-bundle.md)
+    - [nix config](command-ref/new-cli/nix3-config.md)
+    - [nix config show](command-ref/new-cli/nix3-config-show.md)
     - [nix copy](command-ref/new-cli/nix3-copy.md)
     - [nix daemon](command-ref/new-cli/nix3-daemon.md)
     - [nix derivation](command-ref/new-cli/nix3-derivation.md)
diff --git a/doc/manual/src/command-ref/new-cli/nix3-config-show.md b/doc/manual/src/command-ref/new-cli/nix3-config-show.md
new file mode 100644
index 000000000..a39cd13e9
--- /dev/null
+++ b/doc/manual/src/command-ref/new-cli/nix3-config-show.md
@@ -0,0 +1 @@
+{{#include @generated@/command-ref/new-cli/nix3-config-show.md}}
diff --git a/doc/manual/src/command-ref/new-cli/nix3-config.md b/doc/manual/src/command-ref/new-cli/nix3-config.md
new file mode 100644
index 000000000..ba824c7bc
--- /dev/null
+++ b/doc/manual/src/command-ref/new-cli/nix3-config.md
@@ -0,0 +1 @@
+{{#include @generated@/command-ref/new-cli/nix3-config.md}}
diff --git a/doc/manual/src/command-ref/new-cli/nix3-show-config.md b/doc/manual/src/command-ref/new-cli/nix3-show-config.md
deleted file mode 100644
index 060fc065d..000000000
--- a/doc/manual/src/command-ref/new-cli/nix3-show-config.md
+++ /dev/null
@@ -1 +0,0 @@
-{{#include @generated@/command-ref/new-cli/nix3-show-config.md}}