[ci] Switch to travis's Rust build for improved performance

Author: gnunicorn

.travis.yml

@@ -1,7 +1,7 @@
 # Request an environment that provides sudo (that goes with larger containers)
 # and a minimal language environment.
 sudo: true
-language: minimal
+language: rust
 
 cache: cargo
 
@@ -13,13 +13,18 @@ env:
   global:
     - RUST_BACKTRACE=1
   matrix:
-    - RUST_TOOLCHAIN=nightly TARGET=wasm
-    - RUST_TOOLCHAIN=stable TARGET=native
+    - rust: stable
+      env: TARGET=native
+    - rust: nightly
+      env: TARGET=wasm
 
 before_install:
-  # Check how much space we've got on this machine.
+    # Check how much space we've got on this machine.
   - df -h
 
+install:
+  - travis_wait 30 cargo update --locked
+
 script:
   - ./ci/script.sh
 

ci/script.sh

@@ -2,16 +2,6 @@
 
 set -eux
 
-# Install rustup and the specified rust toolchain.
-curl https://sh.rustup.rs -sSf | sh -s -- --default-toolchain=$RUST_TOOLCHAIN -y
-
-# Load cargo environment. Specifically, put cargo into PATH.
-source ~/.cargo/env
-
-rustc --version
-rustup --version
-cargo --version
-
 case $TARGET in
 	"native")
 		sudo apt-get -y update