Tools: Fix Windows build and improve CI error handling

.github/workflows/github-actions-main.yml

@@ -86,10 +86,20 @@ jobs:
           GH_TOKEN: ${{ secrets.GH_TOKEN }}
           IS_CONTINUOUS_INTEGRATION: 1
           BUILD_SEQUENCIAL: 1
+        # To ensure that the operations stop on failure, all commands
+        # should be on one line with "&&" in between.
         run: |
-          yarn install
+          yarn install && cd packages/app-desktop && yarn run dist
-          cd packages/app-desktop
+
-          yarn run dist
+      # Build and package the Windows app, without publishing it, just to
+      # verify that the build process hasn't been broken.
+      - name: Build Windows app (no publishing)
+        if: runner.os == 'Windows' && !startsWith(github.ref, 'refs/tags/v')
+        env:
+          IS_CONTINUOUS_INTEGRATION: 1
+          BUILD_SEQUENCIAL: 1
+        run: |
+          yarn install && cd packages/app-desktop && yarn run dist --publish=never
 
   ServerDockerImage:
     runs-on: ${{ matrix.os }}

packages/app-desktop/tools/compileScripts.js

@@ -30,7 +30,10 @@ function convertJsx(path) {
 
 		if (fileIsNewerThan(jsxPath, jsPath)) {
 			console.info(`Compiling ${jsxPath}...`);
-			const result = spawnSync('yarn', ['run', 'babel', '--presets', 'react', '--out-file', jsPath, jsxPath]);
+
+			// { shell: true } is needed to get it working on Windows:
+			// https://discourse.joplinapp.org/t/attempting-to-build-on-windows/22559/12
+			const result = spawnSync('yarn', ['run', 'babel', '--presets', 'react', '--out-file', jsPath, jsxPath], { shell: true });
 			if (result.status !== 0) {
 				const msg = [];
 				if (result.stdout) msg.push(result.stdout.toString());