build: fail if not inside git clone

related: https://github.com/spesmilo/electrum/issues/8284

contrib/android/make_apk.sh

@@ -10,6 +10,8 @@ LOCALE="$PROJECT_ROOT"/electrum/locale/
 
 . "$CONTRIB"/build_tools_util.sh
 
+git -C "$PROJECT_ROOT" rev-parse 2>/dev/null || fail "Building outside a git clone is not supported."
+
 
 # arguments have been checked in build.sh
 export ELEC_APK_GUI=$1

contrib/build-linux/appimage/make_appimage.sh

@@ -12,6 +12,10 @@ CACHEDIR="$CONTRIB_APPIMAGE/.cache/appimage"
 export DLL_TARGET_DIR="$CACHEDIR/dlls"
 PIP_CACHE_DIR="$CONTRIB_APPIMAGE/.cache/pip_cache"
 
+. "$CONTRIB"/build_tools_util.sh
+
+git -C "$PROJECT_ROOT" rev-parse 2>/dev/null || fail "Building outside a git clone is not supported."
+
 export GCC_STRIP_BINARIES="1"
 
 # pinned versions
@@ -22,8 +26,6 @@ PKG2APPIMAGE_COMMIT="a9c85b7e61a3a883f4a35c41c5decb5af88b6b5d"
 VERSION=$(git describe --tags --dirty --always)
 APPIMAGE="$DISTDIR/electrum-$VERSION-x86_64.AppImage"
 
-. "$CONTRIB"/build_tools_util.sh
-
 rm -rf "$BUILDDIR"
 mkdir -p "$APPDIR" "$CACHEDIR" "$PIP_CACHE_DIR" "$DISTDIR" "$DLL_TARGET_DIR"
 

contrib/build-linux/sdist/make_sdist.sh

@@ -10,6 +10,8 @@ LOCALE="$PROJECT_ROOT/electrum/locale"
 
 . "$CONTRIB"/build_tools_util.sh
 
+git -C "$PROJECT_ROOT" rev-parse 2>/dev/null || fail "Building outside a git clone is not supported."
+
 # note that at least py3.7 is needed, to have https://bugs.python.org/issue30693
 python3 --version || fail "python interpreter not found"
 

contrib/build-wine/make_win.sh

@@ -35,6 +35,8 @@ export WINE_PYTHON="wine $WINE_PYHOME/python.exe -OO -B"
 
 . "$CONTRIB"/build_tools_util.sh
 
+git -C "$PROJECT_ROOT" rev-parse 2>/dev/null || fail "Building outside a git clone is not supported."
+
 info "Clearing $here/build and $here/dist..."
 rm "$here"/build/* -rf
 rm "$here"/dist/* -rf

contrib/osx/make_osx.sh

@@ -25,6 +25,8 @@ mkdir -p "$CACHEDIR" "$DLL_TARGET_DIR"
 
 cd "$PROJECT_ROOT"
 
+git -C "$PROJECT_ROOT" rev-parse 2>/dev/null || fail "Building outside a git clone is not supported."
+
 
 which brew > /dev/null 2>&1 || fail "Please install brew from https://brew.sh/ to continue"
 which xcodebuild > /dev/null 2>&1 || fail "Please install xcode command line tools to continue"