Fix ordering regression: use fixed-point loop for patch detection

The simplified single-pass algorithm assumed patch_release_client.txt was
ordered by dependency (dependencies before dependents). In reality it's
alphabetical. This caused dependents like azure-messaging-eventhubs-
checkpointstore-blob to be missed when they appeared before their
dependency (azure-storage-blob) in the iteration order.

Replace the single foreach with a do/while fixed-point loop that iterates
until no new patches are found, making the algorithm correct regardless of
artifact ordering.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: XiaofeiCao

eng/scripts/Generate-Patch.ps1

@@ -19,6 +19,9 @@
 #
 # 7. CreateNewBranch        - Whether to create a new branch or use an existing branch. You would want to use an existing branch if you are using the same release tag for multiple libraries.
 #
+# 8. UseCurrentBranch       - When set, creates patch branches from the current branch instead of remote main.
+#                             Useful for local testing and dry-runs without requiring changes to be merged first. This is not a required parameter.
+#
 # Example:  .\eng\scripts\Generate-Patch.ps1 -ArtifactName azure-mixedreality-remoterendering -ServiceDirectory remoterendering -ReleaseVersion 1.0.0 -PatchVersion 1.0.1
 # This creates a remote branch "release/azure-mixedreality-remoterendering" with all the necessary changes.
 

eng/scripts/patchhelpers.ps1

@@ -102,9 +102,8 @@ function UpdateCIInformation($ArtifactInfos) {
 }
 
 # Find all the artifacts that will need to be patched based on dependency analysis.
-# Artifacts are processed in the same order as defined in patch_release_client.txt
-# (dependencies appear before dependents). This guarantees cascading: if a dependency
-# is patched, all its dependents will be included as well.
+# Iterates until no more patches are found (fixed-point), so the result is correct
+# regardless of artifact ordering in patch_release_client.txt.
 # Only dependencies that are themselves in the patch list are checked — external
 # dependencies (reactor-core, jackson, etc.) are ignored.
 function FindArtifactsThatNeedPatching($ArtifactInfos) {
@@ -113,18 +112,23 @@ function FindArtifactsThatNeedPatching($ArtifactInfos) {
         $latestVersions[$arId] = $ArtifactInfos[$arId].LatestGAOrPatchVersion
     }
 
-    foreach ($arId in $ArtifactInfos.Keys) {
-        $arInfo = $ArtifactInfos[$arId]
-        foreach ($depId in $arInfo.Dependencies.Keys) {
-            if (-not $latestVersions.ContainsKey($depId)) { continue }
-            if ($arInfo.Dependencies[$depId] -ne $latestVersions[$depId]) {
-                $patchVersion = GetPatchVersion -ReleaseVersion $arInfo.LatestGAOrPatchVersion
-                $arInfo.FutureReleasePatchVersion = $patchVersion
-                $latestVersions[$arId] = $patchVersion
-                break
+    do {
+        $changed = $false
+        foreach ($arId in $ArtifactInfos.Keys) {
+            $arInfo = $ArtifactInfos[$arId]
+            if ($arInfo.FutureReleasePatchVersion) { continue }
+            foreach ($depId in $arInfo.Dependencies.Keys) {
+                if (-not $latestVersions.ContainsKey($depId)) { continue }
+                if ($arInfo.Dependencies[$depId] -ne $latestVersions[$depId]) {
+                    $patchVersion = GetPatchVersion -ReleaseVersion $arInfo.LatestGAOrPatchVersion
+                    $arInfo.FutureReleasePatchVersion = $patchVersion
+                    $latestVersions[$arId] = $patchVersion
+                    $changed = $true
+                    break
+                }
             }
         }
-    }
+    } while ($changed)
 }
 
 # Update dependencies in the version client file.

eng/scripts/tests/patchhelpers.tests.ps1

@@ -177,6 +177,44 @@ Describe "FindArtifactsThatNeedPatching" {
         # azure-core is flagged once (patch version = 1.41.1, not 1.41.2)
         $infos["azure-core"].FutureReleasePatchVersion | Should -Be "1.41.1"
     }
+
+    It "Unordered hashtable: cascading still works when iteration order is non-deterministic" {
+        # Production callers (patchreleases.ps1) pass plain @{} not [ordered]@{}.
+        # With an unordered hashtable the iteration order is undefined, so the
+        # fixed-point loop must converge regardless.
+        $infos = @{
+            "azure-identity" = (New-TestArtifactInfo -ArtifactId "azure-identity" -LatestGAOrPatchVersion "1.10.0" -Dependencies @{
+                "azure-core" = "1.41.0"
+            })
+            "azure-json" = (New-TestArtifactInfo -ArtifactId "azure-json" -LatestGAOrPatchVersion "1.4.0" -Dependencies @{})
+            "azure-core" = (New-TestArtifactInfo -ArtifactId "azure-core" -LatestGAOrPatchVersion "1.41.0" -Dependencies @{
+                "azure-json" = "1.3.0"
+            })
+        }
+        FindArtifactsThatNeedPatching -ArtifactInfos $infos
+        $infos["azure-json"].FutureReleasePatchVersion | Should -BeNullOrEmpty
+        $infos["azure-core"].FutureReleasePatchVersion | Should -Be "1.41.1"
+        $infos["azure-identity"].FutureReleasePatchVersion | Should -Be "1.10.1"
+    }
+
+    It "Handles out-of-order: dependent listed before its dependency (checkpointstore scenario)" {
+        # checkpointstore appears BEFORE blob in the iteration order (alphabetical in patch_release_client.txt).
+        # blob gets patched because its own dep (storage-common) was independently released.
+        # checkpointstore must still be patched even though it's iterated first.
+        $infos = [ordered]@{
+            "azure-storage-common" = (New-TestArtifactInfo -ArtifactId "azure-storage-common" -LatestGAOrPatchVersion "12.32.2" -Dependencies @{})
+            "azure-messaging-eventhubs-checkpointstore-blob" = (New-TestArtifactInfo -ArtifactId "azure-messaging-eventhubs-checkpointstore-blob" -LatestGAOrPatchVersion "1.21.4" -Dependencies @{
+                "azure-storage-blob" = "12.33.2"
+            })
+            "azure-storage-blob" = (New-TestArtifactInfo -ArtifactId "azure-storage-blob" -LatestGAOrPatchVersion "12.33.2" -Dependencies @{
+                "azure-storage-common" = "12.32.1"
+            })
+        }
+        FindArtifactsThatNeedPatching -ArtifactInfos $infos
+        $infos["azure-storage-common"].FutureReleasePatchVersion | Should -BeNullOrEmpty
+        $infos["azure-storage-blob"].FutureReleasePatchVersion | Should -Be "12.33.3"
+        $infos["azure-messaging-eventhubs-checkpointstore-blob"].FutureReleasePatchVersion | Should -Be "1.21.5"
+    }
 }
 
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