ci(windows): don't use a container

Windows containers in GitHub Actions are simply bad. While it is
possible to use them, it is a horrible hack with terrible usability.

It was a fun experiment, but I don't want anybody to maintain this mess,
especially when you can use a normal Windows image (less cool, bloated,
but well supported).

.github/workflows/ci.yaml

@@ -27,11 +27,9 @@ jobs:
     - name: Install dependencies
       run: |
         apt-get -y update
-        apt-get -y install --no-install-recommends ${{ matrix.compiler }} lld meson pkgconf git ca-certificates locales-all python3-pip
+        apt-get -y install --no-install-recommends ${{ matrix.compiler }} lld meson pkgconf git ca-certificates locales-all python3-pip catch2 nlohmann-json3-dev
 
     - uses: actions/checkout@v2
-      with:
-        submodules: true
 
     - name: Check toml.hpp
       run: |
@@ -50,18 +48,6 @@ jobs:
     - name: Test
       run: meson test -C build --verbose
 
-  # The Windows job is a mess, but it's a mess with some advantages.
-  # The job is ran in a clean Docker container, and we have full control on
-  # the software present there. This also means that every single program
-  # needs to be manually installed, and since Windows doesn't have a
-  # package manager installing stuff in scripts is pure pain.
-  # Also, GitHub's support for Windows containers is really, really bad,
-  # and the only way of running a job in Docker is by passing everything to
-  # `docker run`, as a single cmd.exe command.
-  # Lastly, altering the PATH is almost impossible, and as far as I know
-  # the only thing that does that reliably is vcvars64.bat; so to make an
-  # executable available it is necessary to manually move it in a directory
-  # already in Path, like C:\vs\Common7\Tools\
   windows:
     strategy:
       fail-fast: false
@@ -75,35 +61,22 @@ jobs:
         shell: cmd
 
     steps:
-    # When the job is triggered by a pull request, we need to fetch the
-    # "test" merge commit with this command. More info here:
-    # https://docs.github.com/en/rest/reference/pulls#get-a-pull-request
-    - name: pull_request fetch command
-      if: github.event_name == 'pull_request'
-      run: echo pull_request_fetch_command=git fetch origin +${{ github.event.pull_request.merge_commit_sha }}:${{ github.ref_name }} ^&^& >> %GITHUB_ENV%
-
-    - name: Docker
-      run: docker run mcr.microsoft.com/windows/servercore:ltsc2022 cmd.exe /c "
-        mkdir C:\dev &&
-        cd C:\dev &&
-        curl -LO https://aka.ms/vs/17/release.ltsc.17.0/vs_buildtools.exe &&
-        .\vs_buildtools.exe --installPath C:\vs --quiet --norestart --wait --nocache --add Microsoft.VisualStudio.Component.VC.Tools.x86.x64 --add Microsoft.VisualStudio.Component.Windows10SDK.19041 &&
-        C:\vs\VC\Auxiliary\Build\vcvars64.bat &&
-        curl -Lo meson.msi https://github.com/mesonbuild/meson/releases/download/0.61.1/meson-0.61.1-64.msi &&
-        msiexec /a meson.msi TARGETDIR=C:\meson /quiet /qn &&
-        move C:\meson\Meson\* C:\vs\Common7\Tools\ &&
-        curl -Lo git.zip https://github.com/git-for-windows/git/releases/download/v2.35.1.windows.2/MinGit-2.35.1.2-busybox-64-bit.zip &&
-        mkdir git &&
-        cd git &&
-        tar -xf ..\git.zip &&
-        cd .. &&
-        move git\cmd\* C:\vs\Common7\Tools\ &&
-        move git\etc C:\vs\Common7\ &&
-        move git\mingw64 C:\vs\Common7\ &&
-        move git\usr C:\vs\Common7\ &&
-        git clone ${{ github.repositoryUrl }} &&
-        cd tomlplusplus && ${{ env.pull_request_fetch_command }}
-        git checkout ${{ github.ref_name }} &&
-        meson setup -Dcompile_library=${{ matrix.compile }} -Dpedantic=true -Dbuild_tests=true -Dbuild_examples=true -Dgenerate_cmake_config=false build &&
-        meson compile -C build &&
-        meson test -C build"
+    - name: Install dependencies
+      run: |
+        python3 -m pip install -U pip==21.3.1
+        pip3 install meson ninja
+
+    - uses: actions/checkout@v2
+      with:
+        submodules: true
+
+    - uses: ilammy/msvc-dev-cmd@v1
+
+    - name: Configure Meson
+      run: meson setup --vsenv -Dcompile_library=${{ matrix.compile }} -Dpedantic=true -Dbuild_tests=true -Dbuild_examples=true -Dgenerate_cmake_config=false build
+
+    - name: Build
+      run: meson compile -C build
+
+    - name: Test
+      run: meson test -C build --verbose