feat: add rattler_vfs crate

.github/workflows/e2e-rattler-vfs-tests.yml

@@ -0,0 +1,113 @@
+on:
+  push:
+    branches: [main]
+  pull_request:
+    paths:
+      - crates/rattler_vfs/**
+      - scripts/e2e/rattler-vfs-mount.nu
+      - test-data/rattler-vfs/**
+      - .github/workflows/e2e-rattler-vfs-tests.yml
+
+name: E2E rattler-vfs Mount Tests
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
+env:
+  RUST_LOG: info
+  RUST_BACKTRACE: 1
+  CARGO_TERM_COLOR: always
+
+jobs:
+  e2e-mount:
+    name: ${{ matrix.os }}
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [ubuntu-latest, macos-14, windows-latest]
+
+    env:
+      SCCACHE_GHA_ENABLED: "true"
+
+    steps:
+      - name: Checkout source code
+        uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+        with:
+          submodules: recursive
+
+      - uses: prefix-dev/setup-pixi@82d477f15f3a381dbcc8adc1206ce643fe110fb7 # v0.9.3
+        with:
+          environments: rattler-vfs
+
+      - name: Install FUSE (Linux)
+        if: runner.os == 'Linux'
+        run: sudo apt-get update && sudo apt-get install -y fuse3
+
+      - name: Install NFS client (Linux)
+        if: runner.os == 'Linux'
+        run: sudo apt-get install -y nfs-common
+
+      - name: Enable ProjFS (Windows)
+        if: runner.os == 'Windows'
+        shell: powershell
+        run: Enable-WindowsOptionalFeature -Online -FeatureName Client-ProjFS -NoRestart
+
+      # `rattler mount` resolves its package cache via dirs::cache_dir()
+      # (RATTLER_CACHE_DIR is unset here): ~/.cache on Linux,
+      # ~/Library/Caches on macOS, ~/AppData/Local on Windows. Only the
+      # path for the current OS exists; actions/cache ignores the others.
+      - name: Cache conda packages
+        uses: actions/cache@0057852bfaa89a56745cba8c7296529d2fc39830 # v4
+        with:
+          path: |
+            ~/.cache/rattler/cache/pkgs
+            ~/Library/Caches/rattler/cache/pkgs
+            ~/AppData/Local/rattler/cache/pkgs
+          key: rattler-vfs-pkgs-${{ runner.os }}-${{ hashFiles('test-data/rattler-vfs/pixi.lock') }}
+          restore-keys: |
+            rattler-vfs-pkgs-${{ runner.os }}-
+
+      # Read-only tests (includes symlink, network failure, and shutdown tests)
+      - name: FUSE read-only
+        if: runner.os == 'Linux'
+        timeout-minutes: 15
+        env: {TRANSPORT: fuse, OVERLAY: "false"}
+        run: pixi run -e rattler-vfs e2e-rattler-vfs
+
+      - name: NFS read-only
+        if: runner.os != 'Windows'
+        timeout-minutes: 15
+        env: {TRANSPORT: nfs, OVERLAY: "false"}
+        run: pixi run -e rattler-vfs e2e-rattler-vfs
+
+      # Overlay tests (longer timeout: includes persistence, mismatch, shutdown, and stale mount tests)
+      - name: FUSE overlay
+        if: runner.os == 'Linux'
+        timeout-minutes: 15
+        env: {TRANSPORT: fuse, OVERLAY: "true"}
+        run: pixi run -e rattler-vfs e2e-rattler-vfs
+
+      - name: NFS overlay
+        if: runner.os != 'Windows'
+        timeout-minutes: 15
+        env: {TRANSPORT: nfs, OVERLAY: "true"}
+        run: pixi run -e rattler-vfs e2e-rattler-vfs
+
+      - name: ProjFS overlay
+        if: runner.os == 'Windows'
+        timeout-minutes: 15
+        env: {TRANSPORT: projfs, OVERLAY: "true"}
+        run: pixi run -e rattler-vfs e2e-rattler-vfs
+
+      - name: Cleanup mounts
+        if: always()
+        shell: bash
+        run: |
+          for mnt in "${RUNNER_TEMP:-/tmp}"/rattler-vfs-*; do
+            sudo umount -f "$mnt" 2>/dev/null || true
+            fusermount3 -u "$mnt" 2>/dev/null || true
+          done
+          pkill -9 -f 'rattler mount' 2>/dev/null || true
+          taskkill /F /IM rattler.exe 2>/dev/null || true