The prebuild plugin does not run on every build which is expected by the documentation

The prebuild plugin does not run on every build which is expected by the documentation.

I am trying to use the new amazing feature of Swift 5.6 - prebuild plugin and have encountered a flaw in the plugin execution. Maybe I don’t understand how the plugin works.

I used the plugin to auto-generate the build version from the GIT repository information.

From prebuild plugin documentation:
"Commands of type .prebuildCommand run before the start of every build.":
SE-0303
swift-package-manager/Sources/PackagePlugin/Command.swift

The plugin with documentation is located here:
https://github.com/DimaRU/PackageBuildInfo

Sample project:
https://github.com/DimaRU/PackageBuildInfoExample

Shell scripts to reproduce the problem:
https://gist.github.com/DimaRU/964135c00eb3ee3cd3c7abd6f09587c8

Second script (example-clean.sh) force rebuild entire project by clean build artifacts each run.

Scripts execution log:

a-dmitry:~/Developer/temp% ./example.sh
+ git clone https://github.com/DimaRU/PackageBuildInfoExample
Cloning into 'PackageBuildInfoExample'...
remote: Enumerating objects: 34, done.
remote: Counting objects: 100% (34/34), done.
remote: Compressing objects: 100% (29/29), done.
remote: Total 34 (delta 9), reused 26 (delta 3), pack-reused 0
Receiving objects: 100% (34/34), 6.00 KiB | 3.00 MiB/s, done.
Resolving deltas: 100% (9/9), done.
+ cd PackageBuildInfoExample
+ swift run
Fetching https://github.com/DimaRU/PackageBuildInfo from cache
Fetched https://github.com/DimaRU/PackageBuildInfo (1.13s)
Creating working copy for https://github.com/DimaRU/PackageBuildInfo
Working copy of https://github.com/DimaRU/PackageBuildInfo resolved at master
Building for debugging...
[5/5] Linking PackageBuildInfoExample
Build complete! (3.76s)
Build: 1.0.0-2-g727592a
Package build info:
Time:          07.05.2022, 23:29
Branch:        master
Tag:           1.0.0
Commit count:  6
Commits since: 2
ID:            727592a42da716b59d2b0f061dbc614dc9a75892
+ touch a
+ swift run
Building for debugging...
[2/2] Compiling PackageBuildInfoExample packageBuildInfo.swift
Build complete! (0.71s)
Build: 1.0.0-2-g727592a
Package build info:
Time:          07.05.2022, 23:29
Branch:        master
Tag:           1.0.0
Commit count:  6
Commits since: 2
ID:            727592a42da716b59d2b0f061dbc614dc9a75892
+ git add a
+ swift run
Building for debugging...
Build complete! (0.06s)
Build: 1.0.0-2-g727592a
Package build info:
Time:          07.05.2022, 23:29
Branch:        master
Tag:           1.0.0
Commit count:  6
Commits since: 2
ID:            727592a42da716b59d2b0f061dbc614dc9a75892
+ git commit -m 'Add a'
[master b226b81] Add a
 1 file changed, 0 insertions(+), 0 deletions(-)
 create mode 100644 a
+ swift run
Building for debugging...
Build complete! (0.06s)
Build: 1.0.0-2-g727592a
Package build info:
Time:          07.05.2022, 23:29
Branch:        master
Tag:           1.0.0
Commit count:  6
Commits since: 2
ID:            727592a42da716b59d2b0f061dbc614dc9a75892


a-dmitry:~/Developer/temp% ./example-clean.sh
+ git clone https://github.com/DimaRU/PackageBuildInfoExample
Cloning into 'PackageBuildInfoExample'...
remote: Enumerating objects: 34, done.
remote: Counting objects: 100% (34/34), done.
remote: Compressing objects: 100% (29/29), done.
remote: Total 34 (delta 9), reused 26 (delta 3), pack-reused 0
Receiving objects: 100% (34/34), 6.00 KiB | 2.00 MiB/s, done.
Resolving deltas: 100% (9/9), done.
+ cd PackageBuildInfoExample
+ swift run
Fetching https://github.com/DimaRU/PackageBuildInfo from cache
Fetched https://github.com/DimaRU/PackageBuildInfo (0.66s)
Creating working copy for https://github.com/DimaRU/PackageBuildInfo
Working copy of https://github.com/DimaRU/PackageBuildInfo resolved at master
Building for debugging...
[5/5] Linking PackageBuildInfoExample
Build complete! (3.71s)
Build: 1.0.0-2-g727592a
Package build info:
Time:          07.05.2022, 23:29
Branch:        master
Tag:           1.0.0
Commit count:  6
Commits since: 2
ID:            727592a42da716b59d2b0f061dbc614dc9a75892
+ touch a
+ swift package clean
+ swift run
Building for debugging...
[5/5] Linking PackageBuildInfoExample
Build complete! (3.42s)
Build: 1.0.0-2-g727592a
Package build info:
Time:          07.05.2022, 23:29
Branch:        master
Tag:           1.0.0
Commit count:  6
Commits since: 2
ID:            727592a42da716b59d2b0f061dbc614dc9a75892
+ git add a
+ swift package clean
+ swift run
Building for debugging...
[5/5] Linking PackageBuildInfoExample
Build complete! (3.38s)
Build: 1.0.0-2-g727592a-dirty
Package build info:
Time:          07.05.2022, 23:29
Branch:        master
Tag:           1.0.0
Commit count:  6
Commits since: 2
ID:            727592a42da716b59d2b0f061dbc614dc9a75892
Dirty build (have uncommitted changes)
+ git commit -m 'Add a'
[master 331aaee] Add a
 1 file changed, 0 insertions(+), 0 deletions(-)
 create mode 100644 a
+ swift package clean
+ swift run
Building for debugging...
[5/5] Linking PackageBuildInfoExample
Build complete! (3.40s)
Build: 1.0.0-3-g331aaee
Package build info:
Time:          08.05.2022, 09:22
Branch:        master
Tag:           1.0.0
Commit count:  7
Commits since: 3
ID:            331aaeeb8162446b25bb411a67eabb23d1723f9f