docs: ChangesByUserName example ( Fixes #293 )

Examples/ChangesByUserName.ugit.ps1

@@ -0,0 +1,40 @@
+<#
+.SYNOPSIS
+    Generates a Mermaid graph of changes by username.
+.DESCRIPTION
+    Generates a Mermaid graph of changes by username, for the current branch.
+#>
+param()
+
+$gitRemote = git remote
+$headBranch = git remote |
+    Select-Object -First 1 |
+    git remote show |
+    Select-Object -ExpandProperty HeadBranch
+
+$currentBranch = git branch | ? IsCurrentBranch
+if ($currentBranchName -eq $headBranch) {
+    Write-Warning "Not graphing the main branch."
+    return
+}
+
+$currentBranchCommits = git log "$($gitRemote.RemoteName)/$headBranch..$CurrentBranch"
+$changesByUserName = $currentBranchCommits |     
+    Group-Object GitUserName -NoElement
+
+if ($env:GITHUB_STEP_SUMMARY) { 
+"
+~~~mermaid
+$(
+@(
+"pie title Changes by UserName"
+foreach ($changeSet in $changesByUserName) {
+    (' ' * 4) + '"' + $($changeSet.Name) + '"' + ' : ' + ($changeSet.Group.Count)
+}
+) -join [Environment]::NewLine)
+~~~
+
+" |
+        Out-File -Append -FilePath $env:GITHUB_STEP_SUMMARY
+}
+