From 6bd2bb1586f5e480265a42283f823544cc4d1220 Mon Sep 17 00:00:00 2001
From: agneszitte <agnes@platform.uno>
Date: Thu, 4 Apr 2024 14:47:07 -0400
Subject: [PATCH] ci: Adjust CI Build for Doc-Only PRs validations

---
 build/workflow/pipeline.yml                   | 34 +++++----
 build/workflow/stage-determine-changes.yml    | 71 +++++++++++++++++++
 ...dations.yml => stage-docs-validations.yml} |  0
 3 files changed, 91 insertions(+), 14 deletions(-)
 create mode 100644 build/workflow/stage-determine-changes.yml
 rename build/workflow/{stage-validations.yml => stage-docs-validations.yml} (100%)

diff --git a/build/workflow/pipeline.yml b/build/workflow/pipeline.yml
index bfe40468d..579d0f053 100644
--- a/build/workflow/pipeline.yml
+++ b/build/workflow/pipeline.yml
@@ -13,12 +13,8 @@ trigger:
     - '/'
     exclude:
     - .dependabot/
-    - .github/
-    # don't trigger the CI if only docs files are changed
-    - doc/*
-    - '**/*.md'
 
-pr: 
+pr:
   branches:
     include:
       - main
@@ -33,10 +29,6 @@ pr:
     - '/'
     exclude:
     - .dependabot/
-    - .github/
-    # don't trigger the CI if only docs files are changed
-    - doc/*
-    - '**/*.md'
 
 variables:
   # Path where packages (nuget or app packages) will be copied to.
@@ -46,18 +38,32 @@ variables:
   IsReleaseBranch: $[or(eq(variables['Build.SourceBranch'], 'refs/heads/main'), startsWith(variables['Build.SourceBranch'], 'refs/heads/feature/'), startsWith(variables['Build.SourceBranch'], 'refs/heads/release/'))]
 
 stages:
-- stage: Validations
-  displayName: Validations
+- stage: Determine_Changes
+  displayName: Determine Changes
   jobs:
-  - template: stage-validations.yml
+  - template: stage-determine-changes.yml
+
+- stage: Docs_Validations
+  displayName: Docs Validations
+  dependsOn: Determine_Changes
+  # Trigger this stage when docs files are changed
+  condition: or(eq(dependencies.Determine_Changes.outputs['evaluate_changes.DetermineChanges.docsOnly'], 'true'), eq(dependencies.Determine_Changes.outputs['evaluate_changes.DetermineChanges.mixedChanges'], 'true'))
+  jobs:
+  - template: stage-docs-validations.yml
 
 - stage: Packages
-  dependsOn: Validations
+  displayName: Packages
+  dependsOn: Determine_Changes
+  # Don't trigger this stage if only docs files are changed
+  condition: eq(dependencies.Determine_Changes.outputs['evaluate_changes.DetermineChanges.nonDocsOnly'], 'true')
   jobs:
   - template: stage-build-packages.yml
 
 - stage: Tests
-  dependsOn: Validations
+  displayName: Tests
+  dependsOn: Determine_Changes
+  # Don't trigger this stage if only docs files are changed
+  condition: eq(dependencies.Determine_Changes.outputs['evaluate_changes.DetermineChanges.nonDocsOnly'], 'true')
   jobs:
   - template: stage-uitests-wasm.yml
   - template: stage-build-ios.yml
diff --git a/build/workflow/stage-determine-changes.yml b/build/workflow/stage-determine-changes.yml
new file mode 100644
index 000000000..cc44eb6bb
--- /dev/null
+++ b/build/workflow/stage-determine-changes.yml
@@ -0,0 +1,71 @@
+jobs:
+- job: evaluate_changes
+  displayName: 'Check for Doc Only Changes'
+  pool:
+    vmImage: 'ubuntu-latest'
+  steps:
+  - powershell: |
+      # Determine the context of the build (PR or push) and set the target branch accordingly
+      $prTargetBranch = "$(System.PullRequest.TargetBranch)"
+      $isPR = -not [string]::IsNullOrWhiteSpace($prTargetBranch)
+
+      # Normalize the target branch name for PR builds or default to 'main' for push builds
+      $targetBranchName = $isPR ? $prTargetBranch -replace 'refs/heads/', '' : "main"
+      Write-Host "Build context determined: $(if ($isPR) { 'Pull Request targeting ' + $targetBranchName } else { 'Push' })"
+
+      # Fetch the target or default base branch and determine the merge base
+      git fetch origin $targetBranchName
+      $mergeBase = git merge-base HEAD "origin/$targetBranchName"
+      Write-Host "Merge base with '$targetBranchName' identified at $mergeBase"
+
+      Write-Host "Comparing changes from $mergeBase..."
+      $gitDiffCommand = "git diff $mergeBase --name-only"
+      $changedFiles = Invoke-Expression $gitDiffCommand
+      $docsOnly = $false
+      $nonDocsOnly = $false
+      $mixedChanges = $false
+      $docFiles = 0
+      $nonDocFiles = 0
+
+      if ($changedFiles) {
+          Write-Host "Changed files:"
+          Write-Host $changedFiles
+      } else {
+          Write-Host "No files have changed."
+      }
+
+      foreach ($file in $changedFiles -split "`n") {
+          $isDoc = $file.StartsWith("doc/") -or ($file -match "^[^/]+\.md$") -or ($file -match "^\.github/.*\.md$")
+          
+          if ($isDoc) {
+              $docFiles++
+          } else {
+              $nonDocFiles++
+          }
+      }
+
+      Write-Host "Documentation files changed: $docFiles"
+      Write-Host "Non-documentation files changed: $nonDocFiles"
+
+      if ($docFiles -gt 0 -and $nonDocFiles -eq 0) {
+          $docsOnly = $true
+          Write-Host "All changes are documentation-only."
+      } elseif ($docFiles -gt 0 -and $nonDocFiles -gt 0) {
+          $mixedChanges = $true
+          Write-Host "Mixed changes detected: Both documentation and non-documentation files have been modified."
+      } elseif ($nonDocFiles -gt 0) {
+          $nonDocsOnly = $true
+          Write-Host "Non-documentation changes detected."
+      }
+
+      # Explicitly write the final values for clarity
+      Write-Host "Final values:"
+      Write-Host "docsOnly: $docsOnly"
+      Write-Host "nonDocsOnly: $nonDocsOnly"
+      Write-Host "mixedChanges: $mixedChanges"
+
+      # Output the results as pipeline variables
+      Write-Host "##vso[task.setvariable variable=docsOnly;isOutput=true]$docsOnly"
+      Write-Host "##vso[task.setvariable variable=nonDocsOnly;isOutput=true]$nonDocsOnly"
+      Write-Host "##vso[task.setvariable variable=mixedChanges;isOutput=true]$mixedChanges"
+    name: DetermineChanges
diff --git a/build/workflow/stage-validations.yml b/build/workflow/stage-docs-validations.yml
similarity index 100%
rename from build/workflow/stage-validations.yml
rename to build/workflow/stage-docs-validations.yml