From f1a1c270945d0a553b437f2f0ed757e4c0c3d2d4 Mon Sep 17 00:00:00 2001
From: Malcolm Nixon <Malcolm.Nixon@hiarc.inc>
Date: Tue, 21 Jul 2026 17:12:48 -0400
Subject: [PATCH 1/3] Fix MSI installer to always replace any existing version

Installing SysML2Workbench previously only replaced strictly-older
versions and could leave two side-by-side Add/Remove Programs entries
when a prerelease and its stable release computed to the identical
MSI ProductVersion (build.yaml truncated the SemVer prerelease suffix
naively). Fixes both problems:

- build.yaml: compute the MSI build field as patch*1000 +
  prerelease-number, reserving 999 for stable releases, so every
  prerelease/patch/stable combination gets a distinct, monotonically
  increasing MSI version and never collides.
- Package.wxs: MajorUpgrade now uses AllowDowngrades="yes" so
  installing SysML2Workbench always replaces whatever version is
  already present - older, same, or newer - rather than ever
  refusing to install.
- Installer.wixproj: suppress ICE61, a known false positive for
  AllowDowngrades (it expects an Upgrade table Maximum version, which
  AllowDowngrades intentionally omits).

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
---
 .github/workflows/build.yaml                  | 39 ++++++++++++++++++-
 ...nsulting.SysML2Workbench.Installer.wixproj |  6 +++
 .../Package.wxs                               |  8 +++-
 3 files changed, 50 insertions(+), 3 deletions(-)

diff --git a/.github/workflows/build.yaml b/.github/workflows/build.yaml
index 4992232..4e4ed33 100644
--- a/.github/workflows/build.yaml
+++ b/.github/workflows/build.yaml
@@ -234,9 +234,44 @@ jobs:
         if: matrix.os == 'windows-latest'
         shell: bash
         run: |
-          MSI_VERSION=$(echo "${{ inputs.version }}" | cut -d'-' -f1)
+          # MSI ProductVersion only supports three numeric fields (major.minor.build, each
+          # 0-65535) and cannot represent a SemVer prerelease suffix (e.g. "-beta.12").
+          # Naively truncating at the first '-' collapses every prerelease of a version
+          # (and its eventual stable release) onto the identical MSI version number, so
+          # Windows Installer cannot tell a newer prerelease/stable build apart from an
+          # older one already installed - MajorUpgrade then leaves the old install in
+          # place and adds a second, independent Add/Remove Programs entry instead of
+          # replacing it. Encode patch+prerelease into the build field instead:
+          # build = patch*1000 + prerelease-number, reserving 999 for stable (non-
+          # prerelease) releases so a stable release always sorts above every prerelease
+          # of the same patch.
+          FULL_VERSION="${{ inputs.version }}"
+          NUMERIC_PART="${FULL_VERSION%%-*}"
+          MAJOR=$(echo "$NUMERIC_PART" | cut -d'.' -f1)
+          MINOR=$(echo "$NUMERIC_PART" | cut -d'.' -f2)
+          PATCH=$(echo "$NUMERIC_PART" | cut -d'.' -f3)
+
+          if [ "$FULL_VERSION" = "$NUMERIC_PART" ]; then
+            # Stable release - reserve the top of this patch's build range.
+            PRERELEASE_NUM=999
+          else
+            PRERELEASE_PART="${FULL_VERSION#*-}"
+            PRERELEASE_NUM=$(echo "$PRERELEASE_PART" | grep -oE '[0-9]+$')
+            if [ -z "$PRERELEASE_NUM" ] || [ "$PRERELEASE_NUM" -ge 999 ]; then
+              echo "Error: prerelease number in '${FULL_VERSION}' must be a non-negative integer less than 999" >&2
+              exit 1
+            fi
+          fi
+
+          BUILD=$((PATCH * 1000 + PRERELEASE_NUM))
+          if [ "$BUILD" -gt 65535 ]; then
+            echo "Error: computed MSI build number ${BUILD} exceeds the 65535 field limit" >&2
+            exit 1
+          fi
+
+          MSI_VERSION="${MAJOR}.${MINOR}.${BUILD}"
           echo "MSI_VERSION=${MSI_VERSION}" >> "$GITHUB_ENV"
-          echo "Computed MSI version: ${MSI_VERSION}"
+          echo "Computed MSI version: ${MSI_VERSION} (from ${FULL_VERSION})"
 
       - name: Build MSI installer
         if: matrix.os == 'windows-latest'
diff --git a/src/DemaConsulting.SysML2Workbench.Installer/DemaConsulting.SysML2Workbench.Installer.wixproj b/src/DemaConsulting.SysML2Workbench.Installer/DemaConsulting.SysML2Workbench.Installer.wixproj
index ed75346..e6811d4 100644
--- a/src/DemaConsulting.SysML2Workbench.Installer/DemaConsulting.SysML2Workbench.Installer.wixproj
+++ b/src/DemaConsulting.SysML2Workbench.Installer/DemaConsulting.SysML2Workbench.Installer.wixproj
@@ -23,6 +23,12 @@
     <!-- Exposes MSBuild properties as WiX preprocessor variables ($(Version), $(SysML2WorkbenchPublishDir),
          $(SysML2WorkbenchIconFile) in .wxs). -->
     <DefineConstants>Version=$(Version);SysML2WorkbenchPublishDir=$(SysML2WorkbenchPublishDir);SysML2WorkbenchIconFile=$(SysML2WorkbenchIconFile)</DefineConstants>
+    <!-- ICE61 flags this product's Upgrade table as having no Maximum version - that is exactly
+         what Package.wxs's MajorUpgrade AllowDowngrades="yes" intentionally configures, so any
+         version (older, same, or newer) always replaces what's installed instead of ever being
+         refused (see https://docs.firegiant.com/wix/schema/wxs/majorupgrade/). This ICE is a
+         known false positive for that setting and must be suppressed rather than acted on. -->
+    <SuppressIces>ICE61</SuppressIces>
   </PropertyGroup>
 
 </Project>
diff --git a/src/DemaConsulting.SysML2Workbench.Installer/Package.wxs b/src/DemaConsulting.SysML2Workbench.Installer/Package.wxs
index f29a34a..32c54d2 100644
--- a/src/DemaConsulting.SysML2Workbench.Installer/Package.wxs
+++ b/src/DemaConsulting.SysML2Workbench.Installer/Package.wxs
@@ -9,7 +9,13 @@
     Compressed="yes"
     Scope="perMachine">
 
-    <MajorUpgrade DowngradeErrorMessage="A newer version of SysML2 Workbench is already installed." />
+    <!-- AllowDowngrades="yes" means installing SysML2 Workbench always replaces whatever
+         version is already present - older, same, or newer - rather than ever refusing
+         to install or leaving two side-by-side entries in Add/Remove Programs. This also
+         covers the same-version case (WiX docs: "AllowDowngrades already allows two
+         products with the same version number to upgrade each other"), so it must not be
+         combined with AllowSameVersionUpgrades. -->
+    <MajorUpgrade AllowDowngrades="yes" />
     <MediaTemplate EmbedCab="yes" />
 
     <!-- Sets the icon shown in Add/Remove Programs (Apps & Features). -->

From ebaf8b5b0bad8d90fb33f0947d1ba8a641a48665 Mon Sep 17 00:00:00 2001
From: Malcolm Nixon <Malcolm.Nixon@hiarc.inc>
Date: Tue, 21 Jul 2026 17:23:12 -0400
Subject: [PATCH 2/3] Close running app on upgrade, tidy up Add/Remove Programs
 entry

- Package.wxs: add util:CloseApplication so a running SysML2 Workbench
  is closed (gracefully, then forcibly after a short timeout) before
  install/upgrade replaces its files, instead of the upgrade failing
  or silently leaving stale files in use.
- Package.wxs: set ARPHELPLINK/ARPURLINFOABOUT to the project's GitHub
  page and ARPCONTACT to DEMA Consulting, so Add/Remove Programs shows
  useful support/about links instead of nothing.
- Package.wxs: set ARPNOMODIFY/ARPNOREPAIR since there is no WixUI
  dialog sequence to drive those buttons - hide them rather than offer
  non-functional options.
- Installer.wixproj: reference WixToolset.Util.wixext for the
  CloseApplication element.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
---
 ...nsulting.SysML2Workbench.Installer.wixproj |  6 +++++
 .../Package.wxs                               | 26 ++++++++++++++++++-
 2 files changed, 31 insertions(+), 1 deletion(-)

diff --git a/src/DemaConsulting.SysML2Workbench.Installer/DemaConsulting.SysML2Workbench.Installer.wixproj b/src/DemaConsulting.SysML2Workbench.Installer/DemaConsulting.SysML2Workbench.Installer.wixproj
index e6811d4..e35a76d 100644
--- a/src/DemaConsulting.SysML2Workbench.Installer/DemaConsulting.SysML2Workbench.Installer.wixproj
+++ b/src/DemaConsulting.SysML2Workbench.Installer/DemaConsulting.SysML2Workbench.Installer.wixproj
@@ -31,4 +31,10 @@
     <SuppressIces>ICE61</SuppressIces>
   </PropertyGroup>
 
+  <ItemGroup>
+    <!-- Provides the WixCloseApplication custom action used to prompt the user to close
+         a running SysML2 Workbench before the installer replaces its files. -->
+    <PackageReference Include="WixToolset.Util.wixext" Version="5.0.2" />
+  </ItemGroup>
+
 </Project>
diff --git a/src/DemaConsulting.SysML2Workbench.Installer/Package.wxs b/src/DemaConsulting.SysML2Workbench.Installer/Package.wxs
index 32c54d2..4312be8 100644
--- a/src/DemaConsulting.SysML2Workbench.Installer/Package.wxs
+++ b/src/DemaConsulting.SysML2Workbench.Installer/Package.wxs
@@ -1,5 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<Wix xmlns="http://wixtoolset.org/schemas/v4/wxs">
+<Wix xmlns="http://wixtoolset.org/schemas/v4/wxs"
+     xmlns:util="http://wixtoolset.org/schemas/v4/wxs/util">
   <Package
     Name="SysML2 Workbench"
     Manufacturer="DEMA Consulting"
@@ -18,10 +19,33 @@
     <MajorUpgrade AllowDowngrades="yes" />
     <MediaTemplate EmbedCab="yes" />
 
+    <!-- Closes a running SysML2 Workbench before install/upgrade so file replacement never
+         fails because the app is open. Sends a close message first (giving the user a chance
+         to save work), then forcibly terminates it after Timeout seconds if it hasn't exited -
+         RebootPrompt must be "no" to combine with TerminateProcess. -->
+    <util:CloseApplication
+      Id="CloseSysML2Workbench"
+      Target="DemaConsulting.SysML2Workbench.Desktop.exe"
+      Description="SysML2 Workbench is running and will be closed to continue installing."
+      CloseMessage="yes"
+      RebootPrompt="no"
+      TerminateProcess="1"
+      Timeout="5" />
+
     <!-- Sets the icon shown in Add/Remove Programs (Apps & Features). -->
     <Icon Id="AppIcon" SourceFile="$(SysML2WorkbenchIconFile)" />
     <Property Id="ARPPRODUCTICON" Value="AppIcon" />
 
+    <!-- Points Add/Remove Programs' support/about links at the project's GitHub page. -->
+    <Property Id="ARPHELPLINK" Value="https://github.com/demaconsulting/SysML2Workbench" />
+    <Property Id="ARPURLINFOABOUT" Value="https://github.com/demaconsulting/SysML2Workbench" />
+    <Property Id="ARPCONTACT" Value="DEMA Consulting" />
+
+    <!-- There is no WixUI dialog sequence, so the "Modify" and "Repair" buttons in Add/Remove
+         Programs have no UI to drive - hide them rather than offer non-functional options. -->
+    <Property Id="ARPNOMODIFY" Value="1" />
+    <Property Id="ARPNOREPAIR" Value="1" />
+
     <Feature Id="MainFeature" Title="SysML2 Workbench" Level="1">
       <ComponentGroupRef Id="ApplicationFiles" />
       <ComponentRef Id="ApplicationShortcut" />

From 3221518820c9b9228b7a16a3a43d27d8dff08773 Mon Sep 17 00:00:00 2001
From: Malcolm Nixon <Malcolm.Nixon@hiarc.inc>
Date: Tue, 21 Jul 2026 17:39:44 -0400
Subject: [PATCH 3/3] Simplify MSI version computation back to naive truncation

The patch*1000+prerelease-number/999-sentinel encoding was solving a
version-collision bug that AllowDowngrades="yes" (added in the
previous commit) already makes irrelevant - that setting replaces
whatever version is installed regardless of number comparison, so
two builds truncating to the same MSI version is no longer a
problem. Worse, the encoding produced nonsensical Add/Remove Programs
version numbers (e.g. stable 0.1.1 would show as 0.1.1999), so it's
not worth keeping even for display purposes. Reverting to the simple
truncation that was there before.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
---
 .github/workflows/build.yaml | 43 ++++++------------------------------
 1 file changed, 7 insertions(+), 36 deletions(-)

diff --git a/.github/workflows/build.yaml b/.github/workflows/build.yaml
index 4e4ed33..2d83545 100644
--- a/.github/workflows/build.yaml
+++ b/.github/workflows/build.yaml
@@ -235,43 +235,14 @@ jobs:
         shell: bash
         run: |
           # MSI ProductVersion only supports three numeric fields (major.minor.build, each
-          # 0-65535) and cannot represent a SemVer prerelease suffix (e.g. "-beta.12").
-          # Naively truncating at the first '-' collapses every prerelease of a version
-          # (and its eventual stable release) onto the identical MSI version number, so
-          # Windows Installer cannot tell a newer prerelease/stable build apart from an
-          # older one already installed - MajorUpgrade then leaves the old install in
-          # place and adds a second, independent Add/Remove Programs entry instead of
-          # replacing it. Encode patch+prerelease into the build field instead:
-          # build = patch*1000 + prerelease-number, reserving 999 for stable (non-
-          # prerelease) releases so a stable release always sorts above every prerelease
-          # of the same patch.
-          FULL_VERSION="${{ inputs.version }}"
-          NUMERIC_PART="${FULL_VERSION%%-*}"
-          MAJOR=$(echo "$NUMERIC_PART" | cut -d'.' -f1)
-          MINOR=$(echo "$NUMERIC_PART" | cut -d'.' -f2)
-          PATCH=$(echo "$NUMERIC_PART" | cut -d'.' -f3)
-
-          if [ "$FULL_VERSION" = "$NUMERIC_PART" ]; then
-            # Stable release - reserve the top of this patch's build range.
-            PRERELEASE_NUM=999
-          else
-            PRERELEASE_PART="${FULL_VERSION#*-}"
-            PRERELEASE_NUM=$(echo "$PRERELEASE_PART" | grep -oE '[0-9]+$')
-            if [ -z "$PRERELEASE_NUM" ] || [ "$PRERELEASE_NUM" -ge 999 ]; then
-              echo "Error: prerelease number in '${FULL_VERSION}' must be a non-negative integer less than 999" >&2
-              exit 1
-            fi
-          fi
-
-          BUILD=$((PATCH * 1000 + PRERELEASE_NUM))
-          if [ "$BUILD" -gt 65535 ]; then
-            echo "Error: computed MSI build number ${BUILD} exceeds the 65535 field limit" >&2
-            exit 1
-          fi
-
-          MSI_VERSION="${MAJOR}.${MINOR}.${BUILD}"
+          # 0-65535) and cannot represent a SemVer prerelease suffix (e.g. "-beta.12"), so
+          # it's simply truncated off here. Package.wxs's MajorUpgrade AllowDowngrades="yes"
+          # is what makes this safe: it always replaces whatever version is installed -
+          # older, same, or newer - so two builds truncating to the same MSI version (e.g.
+          # a prerelease and its eventual stable release) is not a problem.
+          MSI_VERSION=$(echo "${{ inputs.version }}" | cut -d'-' -f1)
           echo "MSI_VERSION=${MSI_VERSION}" >> "$GITHUB_ENV"
-          echo "Computed MSI version: ${MSI_VERSION} (from ${FULL_VERSION})"
+          echo "Computed MSI version: ${MSI_VERSION}"
 
       - name: Build MSI installer
         if: matrix.os == 'windows-latest'