From bb44aa1bc4e83dcf4ab7cf31bf9ae241b395f86b Mon Sep 17 00:00:00 2001
From: kasperk81 <83082615+kasperk81@users.noreply.github.com>
Date: Mon, 17 Nov 2025 21:56:51 +0200
Subject: [PATCH] Mirror .NET/runtime ICU version range in PowerShell Linux
 packaging (#26304)

---
 tools/packaging/packaging.psm1 | 19 +++++++++++++++++--
 1 file changed, 17 insertions(+), 2 deletions(-)

diff --git a/tools/packaging/packaging.psm1 b/tools/packaging/packaging.psm1
index baeb12e360..8f9cec7179 100644
--- a/tools/packaging/packaging.psm1
+++ b/tools/packaging/packaging.psm1
@@ -2125,6 +2125,22 @@ function Get-PackageDependencies
 
         # These should match those in the Dockerfiles, but exclude tools like Git, which, and curl
         $Dependencies = @()
+
+        # ICU version range follows .NET runtime policy.
+        # See: https://github.com/dotnet/runtime/blob/3fe8518d51bbcaa179bbe275b2597fbe1b88bc5a/src/native/libs/System.Globalization.Native/pal_icushim.c#L235-L243
+        #
+        # Version range rationale:
+        # - The runtime supports ICU versions >= the version it was built against
+        #   and <= that version + 30, to allow sufficient headroom for future releases.
+        # - ICU typically releases about twice per year, so +30 provides roughly
+        #   15 years of forward compatibility.
+        # - On some platforms, the minimum supported version may be lower
+        #   than the build version and we know that older versions just works.
+        #
+        $MinICUVersion = 60                    # runtime minimum supported
+        $BuildICUVersion = 76                  # current build version
+        $MaxICUVersion = $BuildICUVersion + 30 # headroom
+
         if ($Distribution -eq 'deb') {
             $Dependencies = @(
                 "libc6",
@@ -2132,10 +2148,9 @@ function Get-PackageDependencies
                 "libgssapi-krb5-2",
                 "libstdc++6",
                 "zlib1g",
-                "libicu76|libicu74|libicu72|libicu71|libicu70|libicu69|libicu68|libicu67|libicu66|libicu65|libicu63|libicu60|libicu57|libicu55|libicu52",
+                (($MaxICUVersion..$MinICUVersion).ForEach{ "libicu$_" } -join '|'),
                 "libssl3|libssl1.1|libssl1.0.2|libssl1.0.0"
             )
-
         } elseif ($Distribution -eq 'rh') {
             $Dependencies = @(
                 "openssl-libs",