Define the type of artifact to be produced by cargo.

s command `cargo` subcommand is exclusively intended to be used to help
with [working arround](rust-lang/rust#51009)
how crate types are defined, in order to help with cross-platform
builds.

It is currently [not possible](rust-lang/cargo#6160) to define a
single `crate-type` override on `cargo build`, which causes libs
intended to be used on other languages to compile more than one type of
crate.

This commit adds a dependency on this [new CLI app](https://github.com/bltavares/cargo-crate-type) to be able to workaround the limitations of Cargo.

We are now able to enable the `-C lto` optimization again, as we will
only compile a single type of artifact

Signed-off-by: Bruno Tavares <connect+github@bltavares.com>

templates/lib/before_deploy.sh

@@ -5,9 +5,7 @@ PKG_NAME="{{PKG_NAME}}"
 set -ex
 
 main() {
-  local src=$(pwd) \
-  stage \
-  linking_args
+  local src=$(pwd) stage
 
   case $TRAVIS_OS_NAME in
   linux)
@@ -20,17 +18,13 @@ main() {
 
   test -f Cargo.lock || cargo generate-lockfile
 
-  # TODO: combine with -C lto
-  case $TYPE in
-  static)
-    linking_args="--crate-type staticlib"
-    ;;
-  *)
-    linking_args="--crate-type cdylib"
-    ;;
-  esac
+  if [[ "$TYPE" == "static" ]]; then
+    cargo crate-type static
+  else
+    cargo crate-type dynamic
+  fi
 
-  cross rustc --lib --target $TARGET --release -- $linking_args
+  cross rustc --lib --target $TARGET --release -- -C lto
 
   case $TYPE-$TRAVIS_OS_NAME in
   static-*)

templates/lib/install.sh

@@ -46,6 +46,9 @@ main() {
   # Install test dependencies
   rustup component add rustfmt-preview
   rustup component add clippy-preview
+
+  # For defining the type of lib to produce: dynamic OR static
+  cargo install --force cargo-crate-type
 }
 
 main