fix(shellyctl): align PKGBUILD with Arch Go package guidelines

- Add prepare() with GOPATH and go mod download for reproducible builds
- Remove redundant CLI flags from go build, rely on GOFLAGS export
- Add GOPATH="${srcdir}" to build() as recommended by guidelines
- Add check() function running go test
- Fix license file permissions from 0755 to 0644

Co-authored-by: Copilot <copilot@github.com>

PKGBUILD

@@ -1,7 +1,7 @@
 # Maintainer: Markus Pesch <markus.pesch plus apps at cryptic.systems>
 
 pkgname=shellyctl
-pkgver=0.4.0 # renovate: datasource=github-releases depName=jcodybaker/shellyctl
+pkgver=0.4.2 # renovate: datasource=github-releases depName=jcodybaker/shellyctl
 pkgrel=3
 pkgdesc="shellyctl is an unofficial command line client for the Shelly Gen2/3 API. "
 arch=('armv7h' 'aarch64' 'x86_64')
@@ -12,8 +12,21 @@ makedepends=('go')
 source=(
   "$url/archive/refs/tags/v$pkgver.zip"
 )
-sha512sums=('fd997360d5a1804c642422833c602966acd196dc6668d596b5a1d6eefbd619a54154e5a355b705383900374d284e9eef0066c16d9c997c893bddcd4a30ebd647')
-b2sums=('394f831886dd0cf11c8b66feaa0f8a4511a322bdd44eb3cb06794d18b7f215694be00795e96225fe340d945421ec584d6af2afb9fdf1ad1b131d1bd01fc22a55')
+sha512sums=('2c19275204461c0449f4e638cbde8722a0387b147eaa77e2091d160b8c1233d061170ff3600293d116d1740166dacac3cc3ce79549f4558ed8adc5eb45efe224')
+b2sums=('a525fc326b8435c936798214911417cca29251062aa968753d0f2f68eee188e66bf5dca16489cb7fd51818389e931e3d9cdf67376968255ab008a602982845a0')
+
+prepare() {
+  cd "$pkgname-$pkgver"
+
+  export GONOSUMDB="${GONOSUMDB}"
+  export GOPATH="${srcdir}"
+  export GOPROXY="${GOPROXY}"
+
+  # INFO: Print all Go related environment variables for debugging purposes.
+  env | sort | grep -E '^C?GO'
+
+  go mod download -modcacherw
+}
 
 build() {
   cd "$pkgname-$pkgver"
@@ -23,16 +36,15 @@ build() {
   export CGO_CFLAGS="${CFLAGS}"
   export CGO_CXXFLAGS="${CXXFLAGS}"
   export CGO_LDFLAGS="${LDFLAGS}"
+  export GOPATH="${srcdir}"
   export GOFLAGS="-buildmode=pie -trimpath -ldflags=-linkmode=external -mod=readonly -modcacherw"
 
-  go build -v \
-    -trimpath \
-    -buildmode=pie \
-    -mod=readonly \
-    -modcacherw \
-    -ldflags "-linkmode external -extldflags \"${LDFLAGS}\"" \
-    -o $pkgname \
-    .
+  go build -o $pkgname .
+}
+
+check() {
+  cd "$pkgname-$pkgver"
+  go test ./...
 }
 
 package() {
@@ -40,5 +52,5 @@ package() {
   install -D --mode 0755 --target-directory "$pkgdir/usr/bin" "$pkgname-$pkgver/$pkgname"
 
   # license
-  install -D --mode 0755 --target-directory "$pkgdir/usr/share/licenses/$pkgname" "$pkgname-$pkgver/LICENSE.md"
+  install -D --mode 0644 --target-directory "$pkgdir/usr/share/licenses/$pkgname" "$pkgname-$pkgver/LICENSE.md"
 }