Add new `redistribute()` directive (#20185)

Some packages can't be redistributed in source or binary form. We need an explicit way to say that in a package.

This adds a `redistribute()` directive so that package authors can write, e.g.:

```python
    redistribute(source=False, binary=False)
```

You can also do this conditionally with `when=`, as with other directives, e.g.:

```python
    # 12.0 and higher are proprietary
    redistribute(source=False, binary=False, when="@12.0:")

    # can't redistribute when we depend on some proprietary dependency
    redistribute(source=False, binary=False, when="^proprietary-dependency")
```


To prevent Spack from adding either their sources or binaries to public mirrors and build caches. You can still unconditionally add things *if* you run either:
* `spack mirror create --private`
* `spack buildcache push --private`

But the default behavior for build caches is not to include non-redistributable packages in either mirrors or build caches.  We have previously done this manually for our public buildcache, but with this we can start maintaining redistributability directly in packages.

Caveats: currently the default for `redistribute()` is `True` for both `source` and `binary`, and you can only set either of them to `False` via this directive.

- [x] add `redistribute()` directive
- [x] add `redistribute_source` and `redistribute_binary` class methods to `PackageBase`
- [x] add `--private` option to `spack mirror`
- [x] add `--private` option to `spack buildcache push`
- [x] test exclusion of packages from source mirror (both as a root and as a dependency)
- [x] test exclusion of packages from binary mirror (both as a root and as a dependency)

2 files changed, 12 insertions, 6 deletions

diff --git a/share/spack/spack-completion.bash b/share/spack/spack-completion.bash
index 09043cec22..335748cb75 100755
--- a/share/spack/spack-completion.bash
+++ b/share/spack/spack-completion.bash
@@ -571,7 +571,7 @@ _spack_buildcache() {
 _spack_buildcache_push() {
     if $list_options
     then
-        SPACK_COMPREPLY="-h --help -f --force --allow-root -a --unsigned -u --signed --key -k --update-index --rebuild-index --spec-file --only --fail-fast --base-image --tag -t -j --jobs"
+        SPACK_COMPREPLY="-h --help -f --force --allow-root -a --unsigned -u --signed --key -k --update-index --rebuild-index --spec-file --only --fail-fast --base-image --tag -t --private -j --jobs"
     else
         _mirrors
     fi
@@ -580,7 +580,7 @@ _spack_buildcache_push() {
 _spack_buildcache_create() {
     if $list_options
     then
-        SPACK_COMPREPLY="-h --help -f --force --allow-root -a --unsigned -u --signed --key -k --update-index --rebuild-index --spec-file --only --fail-fast --base-image --tag -t -j --jobs"
+        SPACK_COMPREPLY="-h --help -f --force --allow-root -a --unsigned -u --signed --key -k --update-index --rebuild-index --spec-file --only --fail-fast --base-image --tag -t --private -j --jobs"
     else
         _mirrors
     fi
@@ -1428,7 +1428,7 @@ _spack_mirror() {
 _spack_mirror_create() {
     if $list_options
     then
-        SPACK_COMPREPLY="-h --help -d --directory -a --all -f --file --exclude-file --exclude-specs --skip-unstable-versions -D --dependencies -n --versions-per-spec -U --fresh --reuse --reuse-deps --deprecated"
+        SPACK_COMPREPLY="-h --help -d --directory -a --all -f --file --exclude-file --exclude-specs --skip-unstable-versions -D --dependencies -n --versions-per-spec --private -U --fresh --reuse --reuse-deps --deprecated"
     else
         _all_packages
     fi
diff --git a/share/spack/spack-completion.fish b/share/spack/spack-completion.fish
index e4b8689e55..d69f58d701 100755
--- a/share/spack/spack-completion.fish
+++ b/share/spack/spack-completion.fish
@@ -700,7 +700,7 @@ complete -c spack -n '__fish_spack_using_command buildcache' -s h -l help -f -a
 complete -c spack -n '__fish_spack_using_command buildcache' -s h -l help -d 'show this help message and exit'
 
 # spack buildcache push
-set -g __fish_spack_optspecs_spack_buildcache_push h/help f/force a/allow-root u/unsigned signed k/key= update-index spec-file= only= fail-fast base-image= t/tag= j/jobs=
+set -g __fish_spack_optspecs_spack_buildcache_push h/help f/force a/allow-root u/unsigned signed k/key= update-index spec-file= only= fail-fast base-image= t/tag= private j/jobs=
 complete -c spack -n '__fish_spack_using_command_pos_remainder 1 buildcache push' -f -k -a '(__fish_spack_specs)'
 complete -c spack -n '__fish_spack_using_command buildcache push' -s h -l help -f -a help
 complete -c spack -n '__fish_spack_using_command buildcache push' -s h -l help -d 'show this help message and exit'
@@ -726,11 +726,13 @@ complete -c spack -n '__fish_spack_using_command buildcache push' -l base-image
 complete -c spack -n '__fish_spack_using_command buildcache push' -l base-image -r -d 'specify the base image for the buildcache'
 complete -c spack -n '__fish_spack_using_command buildcache push' -l tag -s t -r -f -a tag
 complete -c spack -n '__fish_spack_using_command buildcache push' -l tag -s t -r -d 'when pushing to an OCI registry, tag an image containing all root specs and their runtime dependencies'
+complete -c spack -n '__fish_spack_using_command buildcache push' -l private -f -a private
+complete -c spack -n '__fish_spack_using_command buildcache push' -l private -d 'for a private mirror, include non-redistributable packages'
 complete -c spack -n '__fish_spack_using_command buildcache push' -s j -l jobs -r -f -a jobs
 complete -c spack -n '__fish_spack_using_command buildcache push' -s j -l jobs -r -d 'explicitly set number of parallel jobs'
 
 # spack buildcache create
-set -g __fish_spack_optspecs_spack_buildcache_create h/help f/force a/allow-root u/unsigned signed k/key= update-index spec-file= only= fail-fast base-image= t/tag= j/jobs=
+set -g __fish_spack_optspecs_spack_buildcache_create h/help f/force a/allow-root u/unsigned signed k/key= update-index spec-file= only= fail-fast base-image= t/tag= private j/jobs=
 complete -c spack -n '__fish_spack_using_command_pos_remainder 1 buildcache create' -f -k -a '(__fish_spack_specs)'
 complete -c spack -n '__fish_spack_using_command buildcache create' -s h -l help -f -a help
 complete -c spack -n '__fish_spack_using_command buildcache create' -s h -l help -d 'show this help message and exit'
@@ -756,6 +758,8 @@ complete -c spack -n '__fish_spack_using_command buildcache create' -l base-imag
 complete -c spack -n '__fish_spack_using_command buildcache create' -l base-image -r -d 'specify the base image for the buildcache'
 complete -c spack -n '__fish_spack_using_command buildcache create' -l tag -s t -r -f -a tag
 complete -c spack -n '__fish_spack_using_command buildcache create' -l tag -s t -r -d 'when pushing to an OCI registry, tag an image containing all root specs and their runtime dependencies'
+complete -c spack -n '__fish_spack_using_command buildcache create' -l private -f -a private
+complete -c spack -n '__fish_spack_using_command buildcache create' -l private -d 'for a private mirror, include non-redistributable packages'
 complete -c spack -n '__fish_spack_using_command buildcache create' -s j -l jobs -r -f -a jobs
 complete -c spack -n '__fish_spack_using_command buildcache create' -s j -l jobs -r -d 'explicitly set number of parallel jobs'
 
@@ -2216,7 +2220,7 @@ complete -c spack -n '__fish_spack_using_command mirror' -s n -l no-checksum -f
 complete -c spack -n '__fish_spack_using_command mirror' -s n -l no-checksum -d 'do not use checksums to verify downloaded files (unsafe)'
 
 # spack mirror create
-set -g __fish_spack_optspecs_spack_mirror_create h/help d/directory= a/all f/file= exclude-file= exclude-specs= skip-unstable-versions D/dependencies n/versions-per-spec= U/fresh reuse reuse-deps deprecated
+set -g __fish_spack_optspecs_spack_mirror_create h/help d/directory= a/all f/file= exclude-file= exclude-specs= skip-unstable-versions D/dependencies n/versions-per-spec= private U/fresh reuse reuse-deps deprecated
 complete -c spack -n '__fish_spack_using_command_pos_remainder 0 mirror create' -f -k -a '(__fish_spack_specs)'
 complete -c spack -n '__fish_spack_using_command mirror create' -s h -l help -f -a help
 complete -c spack -n '__fish_spack_using_command mirror create' -s h -l help -d 'show this help message and exit'
@@ -2236,6 +2240,8 @@ complete -c spack -n '__fish_spack_using_command mirror create' -s D -l dependen
 complete -c spack -n '__fish_spack_using_command mirror create' -s D -l dependencies -d 'also fetch all dependencies'
 complete -c spack -n '__fish_spack_using_command mirror create' -s n -l versions-per-spec -r -f -a versions_per_spec
 complete -c spack -n '__fish_spack_using_command mirror create' -s n -l versions-per-spec -r -d 'the number of versions to fetch for each spec, choose \'all\' to retrieve all versions of each package'
+complete -c spack -n '__fish_spack_using_command mirror create' -l private -f -a private
+complete -c spack -n '__fish_spack_using_command mirror create' -l private -d 'for a private mirror, include non-redistributable packages'
 complete -c spack -n '__fish_spack_using_command mirror create' -s U -l fresh -f -a concretizer_reuse
 complete -c spack -n '__fish_spack_using_command mirror create' -s U -l fresh -d 'do not reuse installed deps; build newest configuration'
 complete -c spack -n '__fish_spack_using_command mirror create' -l reuse -f -a concretizer_reuse