diff --git a/packages/pigeon/tool/shared/test_suites.dart b/packages/pigeon/tool/shared/test_suites.dart
index fe86925792aa..2707076c94a8 100644
--- a/packages/pigeon/tool/shared/test_suites.dart
+++ b/packages/pigeon/tool/shared/test_suites.dart
@@ -409,6 +409,15 @@ Future<int> _runLinuxUnitTests({bool ciMode = false}) async {
     return compileCode;
   }
 
+  // Depending on the Flutter version, the build output path may be different.
+  // To handle both master and stable, and to future-proof against the changes
+  // that will happen in https://github.com/flutter/flutter/issues/114349
+  // - Try arm64, to future-proof against arm64 support.
+  // - Try x64, to cover pre-arm64 support on arm64 hosts, as well as x64 hosts.
+  // TODO(gustl22): Remove all this when these tests no longer need to
+  // support a version of Flutter without
+  // https://github.com/flutter/flutter/issues/114349, and just construct the
+  // version of the path with the current architecture.
   const buildDirBase = '$examplePath/build/linux';
   const buildRelativeBinaryPath = 'debug/plugins/test_plugin/test_plugin_test';
   const arm64Path = '$buildDirBase/arm64/$buildRelativeBinaryPath';
diff --git a/script/tool/lib/src/common/cmake.dart b/script/tool/lib/src/common/cmake.dart
index 841d3f25be23..8084f9aee87a 100644
--- a/script/tool/lib/src/common/cmake.dart
+++ b/script/tool/lib/src/common/cmake.dart
@@ -20,7 +20,7 @@ class CMakeProject {
     required this.buildMode,
     this.processRunner = const ProcessRunner(),
     this.platform = const LocalPlatform(),
-    this.arch,
+    required this.arch,
   });
 
   /// The directory of a Flutter project to run Gradle commands in.
@@ -33,13 +33,11 @@ class CMakeProject {
   final Platform platform;
 
   /// The architecture subdirectory of the build.
-  // TODO(stuartmorgan): Make this non-nullable once Flutter 3.13 is no longer
-  // supported, since at that point there will always be a subdirectory.
-  final String? arch;
+  final String arch;
 
   /// The build mode (e.g., Debug, Release).
   ///
-  /// This is a constructor paramater because on Linux many properties depend
+  /// This is a constructor parameter because on Linux many properties depend
   /// on the build mode since it uses a single-configuration generator.
   final String buildMode;
 
@@ -52,10 +50,8 @@ class CMakeProject {
   Directory get buildDirectory {
     Directory buildDir = flutterProject
         .childDirectory('build')
-        .childDirectory(_platformDirName);
-    if (arch != null) {
-      buildDir = buildDir.childDirectory(arch!);
-    }
+        .childDirectory(_platformDirName)
+        .childDirectory(arch);
     if (platform.isLinux) {
       // Linux uses a single-config generator, so the base build directory
       // includes the configuration.
diff --git a/script/tool/lib/src/native_test_command.dart b/script/tool/lib/src/native_test_command.dart
index a944b95b87bc..7d5001c2671f 100644
--- a/script/tool/lib/src/native_test_command.dart
+++ b/script/tool/lib/src/native_test_command.dart
@@ -678,50 +678,35 @@ this command.
     var hasMissingBuild = false;
     var buildFailed = false;
     String? arch;
-    const x64DirName = 'x64';
-    const arm64DirName = 'arm64';
     if (platform.isWindows) {
-      arch = _abi == Abi.windowsX64 ? x64DirName : arm64DirName;
+      arch = switch (_abi) {
+        Abi.windowsX64 => 'x64',
+        Abi.windowsArm64 => 'arm64',
+        _ => null,
+      };
     } else if (platform.isLinux) {
       // TODO(stuartmorgan): Support arm64 if that ever becomes a supported
       // CI configuration for the repository.
+      // See: https://github.com/flutter/flutter/issues/114349
       arch = 'x64';
     }
+
+    if (arch == null) {
+      return _PlatformResult(
+        RunState.failed,
+        error:
+            'Testing on platform and architecture "$_abi" as CMakeProjects is not supported.',
+      );
+    }
+
     for (final RepositoryPackage example in plugin.getExamples()) {
-      var project = CMakeProject(
+      final project = CMakeProject(
         example.directory,
         buildMode: buildMode,
         processRunner: processRunner,
         platform: platform,
         arch: arch,
       );
-      if (platform.isWindows) {
-        if (arch == arm64DirName && !project.isConfigured()) {
-          // Check for x64, to handle builds newer than 3.13, but that don't yet
-          // have https://github.com/flutter/flutter/issues/129807.
-          // TODO(stuartmorgan): Remove this when CI no longer supports a
-          // version of Flutter without the issue above fixed.
-          project = CMakeProject(
-            example.directory,
-            buildMode: buildMode,
-            processRunner: processRunner,
-            platform: platform,
-            arch: x64DirName,
-          );
-        }
-        if (!project.isConfigured()) {
-          // Check again without the arch subdirectory, since 3.13 doesn't
-          // have it yet.
-          // TODO(stuartmorgan): Remove this when CI no longer supports Flutter
-          // 3.13.
-          project = CMakeProject(
-            example.directory,
-            buildMode: buildMode,
-            processRunner: processRunner,
-            platform: platform,
-          );
-        }
-      }
       if (!project.isConfigured()) {
         printError(
           'ERROR: Run "flutter build" on ${example.displayName}, '