ARROW-2520: [Rust] CI should also build against nightly Rust

Author: Krisztián Szűcs <[email protected]>

Closes apache#2477 from kszucs/ARROW-2520 and squashes the following commits:

79b1e7a <Krisztián Szűcs> check against "Rust" in appceyor-install.bat
4a31a42 <Krisztián Szűcs> fix install script
99b99b6 <Krisztián Szűcs> set rust stable toolchain as default after running tests on appveyor
f941121 <Krisztián Szűcs> use rustup environment variable
15b6358 <Krisztián Szűcs> don't parenthesize
07db3d9 <Krisztián Szűcs> make travis_install_cargo executable
8af4c76 <Krisztián Szűcs> test both stable and nightly rust in the same CI step
2720e1e <Krisztián Szűcs> remove rust from allow_failures
c5dd144 <Krisztián Szűcs> separate matrix step
7983976 <Krisztián Szűcs> remove beta channel
40c0ed8 <Krisztián Szűcs> rust against rust nightly

.travis.yml

@@ -212,7 +212,6 @@ matrix:
   # Rust
   - language: rust
     cache: cargo
-    rust: stable
     addons:
       apt:
         packages:
@@ -223,17 +222,15 @@ matrix:
           - cmake
     before_script:
     - if [ $ARROW_CI_RUST_AFFECTED != "1" ]; then exit; fi
-    - pip install 'travis-cargo<0.2' --user && export PATH=$HOME/.local/bin:$PATH
-    - export CARGO_TARGET_DIR=$TRAVIS_BUILD_DIR/target
-    - cargo install cargo-travis || echo "Skipping cargo-travis installation as it already exists in cache"
-    - export PATH=$HOME/.cargo/bin:$PATH
+    - $TRAVIS_BUILD_DIR/ci/travis_install_cargo.sh
     script:
-    - $TRAVIS_BUILD_DIR/ci/travis_script_rust.sh
+    - RUSTUP_TOOLCHAIN=stable $TRAVIS_BUILD_DIR/ci/travis_script_rust.sh
+    - RUSTUP_TOOLCHAIN=nightly $TRAVIS_BUILD_DIR/ci/travis_script_rust.sh || true
     after_success:
     - pushd ${TRAVIS_BUILD_DIR}/rust
     # Run coverage for codecov.io
     - mkdir -p target/kcov
-    - RUST_BACKTRACE=1 cargo coverage --verbose
+    - RUST_BACKTRACE=1 RUSTUP_TOOLCHAIN=stable cargo coverage --verbose
     - bash <(curl -s https://codecov.io/bash) || echo "Codecov did not collect coverage reports"
   # Go
   - language: go

appveyor.yml

@@ -60,8 +60,7 @@ environment:
       GENERATOR: Ninja
       CONFIGURATION: "Release"
       BUILD_SCRIPT: "CMake_Build_Script"
-    - JOB: "Rust_Stable"
-      RUST_VERSION: stable
+    - JOB: "Rust"
       TARGET: x86_64-pc-windows-msvc
       USE_CLCACHE: false
 

ci/appveyor-build.bat

@@ -17,12 +17,26 @@
 
 @echo on
 
-if "%JOB%" == "Rust_Stable" (
-    cd rust
+if "%JOB%" == "Rust" (
+    pushd rust
+
+    rustup default stable
+    rustup show
     cargo build --target %TARGET% || exit /B
     cargo build --target %TARGET% --release || exit /B
     cargo test --target %TARGET% || exit /B
     cargo test --target %TARGET% --release || exit /B
+
+    rustup default nightly
+    rustup show
+    cargo build --target %TARGET%
+    cargo build --target %TARGET% --release
+    cargo test --target %TARGET%
+    cargo test --target %TARGET% --release
+
+    rustup default stable
+
+    popd
 ) else (
     git config core.symlinks true
     git reset --hard

ci/appveyor-install.bat

@@ -17,10 +17,12 @@
 
 @echo on
 
-if "%JOB%" == "Rust_Stable" (
+if "%JOB%" == "Rust" (
     curl -sSf -o rustup-init.exe https://win.rustup.rs/
-    rustup-init.exe -y --default-host %TARGET% --default-toolchain %RUST_VERSION%
+    rustup-init.exe -y --default-host %TARGET% --default-toolchain stable
     set "PATH=%PATH%;C:\Users\Appveyor\.cargo\bin"
+    rustup install stable
+    rustup install nightly
     rustc -Vv
     cargo -V
 ) else (

ci/travis_install_cargo.sh

@@ -0,0 +1,32 @@
+#!/usr/bin/env bash
+
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+
+set -e
+
+# ensure that both toolchains are installed
+rustup install stable
+rustup install nightly
+
+pip install 'travis-cargo<0.2' --user
+
+export PATH=$HOME/.local/bin:$PATH
+export CARGO_TARGET_DIR=$TRAVIS_BUILD_DIR/target
+
+cargo install cargo-travis || echo "Skipping cargo-travis installation as it already exists in cache"
+export PATH=$HOME/.cargo/bin:$PATH

ci/travis_script_rust.sh

@@ -23,9 +23,13 @@ RUST_DIR=${TRAVIS_BUILD_DIR}/rust
 
 pushd $RUST_DIR
 
+# show activated toolchain
+rustup show
+
 # raises on any formatting errors
 rustup component add rustfmt-preview
 cargo fmt --all -- --check
+
 # raises on any warnings
 cargo rustc -- -D warnings