chore/ci: update travis for rust

Author: ustulation

.travis.yml

@@ -8,19 +8,27 @@ os:
   - windows
 language: rust
 rust:
-  - 1.29.0
+  - 1.30.1
 sudo: false
 cache:
   cargo: true
 before_script:
   - if ! cargo prune --version | grep -q "0.1.8"; then
       cargo install cargo-prune --vers="0.1.8" --force;
     fi
-  - if ! rustfmt --version | grep -q "0.99.1-stable"; then
+  - if ! rustfmt --version | grep -q "0.99.4-stable"; then
       rustup component add rustfmt-preview;
+      if ! rustfmt --version | grep -q "0.99.4-stable"; then
+        printf "Bad rustfmt version";
+        exit 1;
+      fi
     fi
   - if ! cargo clippy --version | grep -q "0.0.212"; then
       rustup component add clippy-preview;
+      if ! cargo clippy --version | grep -q "0.0.212"; then
+        printf "Bad clippy version";
+        exit 1;
+      fi
     fi
 script:
   - set -x;