Set up minimal GH Action to build the code

Author: mgeisler

.github/workflows/build.yml

@@ -0,0 +1,44 @@
+name: Build
+
+on:
+  push:
+#    branches: [ master ]
+#  pull_request:
+#    branches: [ master ]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        emacs-version: ['27.2', '28.2', '29.4', '30.1']
+
+    steps:
+    - uses: actions/checkout@v4
+
+    - name: Install Emacs ${{ matrix.emacs-version }}
+      uses: purcell/setup-emacs@master
+      with:
+        version: ${{ matrix.emacs-version }}
+
+    - name: Install build dependencies via Nix
+      run: |
+        # Pin to nixos-24.05 stable release for reproducibility
+        # Note: libvterm is not included - CMake downloads and builds it
+        nix profile install \
+          github:NixOS/nixpkgs/nixos-24.05#cmake \
+          github:NixOS/nixpkgs/nixos-24.05#libtool \
+          github:NixOS/nixpkgs/nixos-24.05#glib
+
+    - name: Build vterm module
+      run: |
+        mkdir build
+        cd build
+        cmake ..
+        make
+
+    - name: Test vterm module
+      run: |
+        cd build
+        make test

CMakeLists.txt

@@ -97,8 +97,23 @@ target_include_directories(vterm INTERFACE ${LIBVTERM_INCLUDE_DIR})
 # Link with libvterm
 target_link_libraries(vterm-module PUBLIC vterm)
 
-# Custom run command for testing
+# Common Emacs command setup for testing
+set(EMACS_LOAD_PATH -L ${CMAKE_SOURCE_DIR} -L ${CMAKE_BINARY_DIR})
+
+# Custom run command for interactive testing
 add_custom_target(run
-  COMMAND emacs -Q -L ${CMAKE_SOURCE_DIR} -L ${CMAKE_BINARY_DIR} --eval "\\(require \\'vterm\\)" --eval "\\(vterm\\)"
+  COMMAND emacs -Q ${EMACS_LOAD_PATH} --eval "(require 'vterm)" --eval "(vterm)"
   DEPENDS vterm-module
+  VERBATIM
+  )
+
+# Enable CMake's built-in testing framework
+enable_testing()
+
+# Test that vterm module loads successfully
+add_test(
+  NAME vterm-load
+  COMMAND emacs --batch -Q ${EMACS_LOAD_PATH}
+    --eval "(require 'vterm)"
+    --eval "(message \"Successfully loaded vterm\")"
   )

README.md

@@ -286,8 +286,14 @@ end
 
 # Debugging and testing
 
-If you have successfully built the module, you can test it by executing the
-following command in the `build` directory:
+If you have successfully built the module, you can test it loads by executing
+the following command in the `build` directory:
+
+```sh
+make test
+```
+
+Test the new module in a clean Emacs with this command in the `build` directory:
 
 ```sh
 make run