ci: use special flutter version on snap (#543)

.github/workflows/build.yml

@@ -258,9 +258,6 @@ jobs:
       - uses: actions/setup-go@v4
         with:
           go-version: ${{ env.GO_VERSION }}
-      - uses: subosito/flutter-action@v2
-        with:
-          flutter-version: ${{ env.FLUTTER_VERSION }}
       - name: Setup LXD
         uses: canonical/[email protected]
         with:
@@ -298,20 +295,50 @@ jobs:
           
           apps:
             gopeed:
-              command: gopeed
+              command: bin/gopeed
               extensions: [gnome]
               plugs:
                 - network
               slots:
                 - dbus-gopeed
           parts:
+            flutter-git:
+              source: https://github.com/flutter/flutter.git
+              source-tag: $FLUTTER_VERSION
+              source-depth: 1
+              plugin: nil
+              override-build: |
+                mkdir -p \$CRAFT_PART_INSTALL/usr/bin
+                mkdir -p \$CRAFT_PART_INSTALL/usr/libexec
+                cp -r \$CRAFT_PART_SRC \$CRAFT_PART_INSTALL/usr/libexec/flutter
+                ln -s \$CRAFT_PART_INSTALL/usr/libexec/flutter/bin/flutter \$CRAFT_PART_INSTALL/usr/bin/flutter
+                ln -s \$SNAPCRAFT_PART_INSTALL/usr/libexec/flutter/bin/dart \$SNAPCRAFT_PART_INSTALL/usr/bin/dart
+                \$CRAFT_PART_INSTALL/usr/bin/flutter doctor
+              build-packages:
+                - clang
+                - cmake
+                - curl
+                - libgtk-3-dev
+                - ninja-build
+                - unzip
+                - xz-utils
+                - zip
+              override-prime: ''
             gopeed:
+              after: [flutter-git]
               source: .
-              plugin: flutter
+              plugin: nil
               stage-packages:
                 - libgtk-3-dev
                 - libappindicator3-dev
-              flutter-target: lib/main.dart
+              override-build: |
+                # work around pub get stack overflow # https://github.com/dart-lang/sdk/issues/51068#issuecomment-1396588253
+                set +e
+                dart pub get
+                set -eux
+                flutter build linux --release -v
+                mkdir -p \$CRAFT_PART_INSTALL/bin/
+                cp -r build/linux/*/release/bundle/* \$CRAFT_PART_INSTALL/bin/
           EOF
           
           cp linux/assets/com.gopeed.Gopeed.desktop snap/gui/gopeed.desktop