fix(update): launch installers after the current app exits

tests/public-release-metadata.test.ts

@@ -142,9 +142,10 @@ function createReleaseFixture(): string {
           to: "assets/app_icon.ico"
         }
       ],
-      nsis: {
-        artifactName: "${productName}-Setup-${version}.${ext}",
-        oneClick: false,
+      nsis: {
+        artifactName: "${productName}-Setup-${version}.${ext}",
+        include: "resources/installer.nsh",
+        oneClick: false,
         perMachine: false,
         allowToChangeInstallationDirectory: true,
         createDesktopShortcut: true
@@ -171,6 +172,7 @@ function createReleaseFixture(): string {
   writeRedistributionFiles(rootDir, true);
   writeFile(rootDir, "assets/app_icon.ico", "application-icon");
   writeFile(rootDir, "win-unpacked/resources/assets/app_icon.ico", "application-icon");
+  writeFile(rootDir, "resources/installer.nsh", "!macro customCheckAppRunning\n${isUpdated}\nFIND_PROCESS\ntaskkill /f /im\n!macroend\n");
 
   return rootDir;
 }
@@ -196,7 +198,7 @@ describe("public release metadata", () => {
     expect(result.missingArtifacts).toEqual([]);
   });
 
-  it("rejects a package configured for a different GitHub owner", () => {
+  it("rejects a package configured for a different GitHub owner", () => {
     const rootDir = createReleaseFixture();
     const packagePath = path.join(rootDir, "package.json");
     const packageJson = JSON.parse(fs.readFileSync(packagePath, "utf8"));
@@ -345,6 +347,16 @@ describe("public release metadata", () => {
     expect(() => verifyPublicRelease(rootDir)).toThrow(/extraResources|LICENSE/);
   });
 
+  it("rejects release metadata without the update-safe NSIS include", () => {
+    const rootDir = createReleaseFixture();
+    const packagePath = path.join(rootDir, "package.json");
+    const packageJson = JSON.parse(fs.readFileSync(packagePath, "utf8"));
+    delete packageJson.build.nsis.include;
+    fs.writeFileSync(packagePath, `${JSON.stringify(packageJson, null, 2)}\n`);
+
+    expect(() => verifyPublicRelease(rootDir)).toThrow(/NSIS|update|installer/i);
+  });
+
   it("rejects a packaged application without its window and tray icon", () => {
     const rootDir = createReleaseFixture();
     fs.rmSync(path.join(rootDir, "win-unpacked", "resources", "assets", "app_icon.ico"));