travis: use latest nightly

.travis.yml

@@ -7,16 +7,11 @@ language: rust
 # sometimes break the build. When cache is enabled do not use the produced WASM build.
 # This also means the binary should not be used to produce the final chainspec file (because the same
 # one is embedded in the binary)
-cache: cargo
+# cache: cargo
 
 rust:
   - stable
 
-matrix:
-  include:
-    - os: linux
-      env: TARGET=x86_64-unknown-linux-gnu
-
 # Skip Rust build in a pull request if no rust project files were modified
 before_install:
   - |
@@ -30,8 +25,8 @@ before_install:
     fi
 
 install:
-  - rustup install nightly-2020-05-23
-  - rustup target add wasm32-unknown-unknown --toolchain nightly-2020-05-23
+  - rustup install nightly
+  - rustup target add wasm32-unknown-unknown --toolchain nightly
   # travis installs rust using rustup with the "minimal" profile so these tools are not installed by default
   - rustup component add rustfmt
   - rustup component add clippy
@@ -41,7 +36,7 @@ before_script:
 
 script:
   # we set release as build type for all steps to benefit from already compiled packages in prior steps
-  - BUILD_DUMMY_WASM_BINARY=1 cargo clippy --release --target=${TARGET} -- -D warnings
-  - BUILD_DUMMY_WASM_BINARY=1 cargo test --release --verbose --all --target=${TARGET}
-  - TRIGGER_WASM_BUILD=1 WASM_BUILD_TOOLCHAIN=nightly-2020-05-23 cargo build --release --target=${TARGET} -p joystream-node
-  - ls -l ./target/${TARGET}/release/wbuild/joystream-node-runtime/
+  - BUILD_DUMMY_WASM_BINARY=1 cargo clippy --release -- -D warnings
+  - BUILD_DUMMY_WASM_BINARY=1 cargo test --release --all
+  - TRIGGER_WASM_BUILD=1 cargo build --release
+  - ls -l ./target/release/wbuild/joystream-node-runtime/