Remove package lock, drop Node.js 11, add 12, bump dependencies

Author: novemberborn

.npmrc

@@ -0,0 +1 @@
+package-lock=false

.travis.yml

@@ -1,33 +1,9 @@
 language: node_js
+os:
+  - linux
 node_js:
-  - '10'
-  - '8'
-  - '6'
-env:
-  - FRESH_DEPS=false
-  - FRESH_DEPS=true
-matrix:
-  exclude:
-    - node_js: '8'
-      env: FRESH_DEPS=true
-    - node_js: '6'
-      env: FRESH_DEPS=true
-cache:
-  directories:
-    - $HOME/.npm
-before_install:
-  - npm install --global [email protected]
-  - npm --version
-install: |
-  if [[ ${FRESH_DEPS} == "true" ]]; then
-    npm install --no-shrinkwrap --prefer-online;
-  else
-    npm ci;
-    checksum=$(md5sum package-lock.json);
-    npm install --package-lock-only;
-    if ! echo ${checksum} | md5sum --quiet -c -; then
-      echo "package-lock.json was modified unexpectedly. Please rebuild it using npm@$(npm -v) and commit the changes.";
-      exit 1;
-    fi
-  fi
-after_success: npx codecov --file=coverage/lcov.info
+  - 12
+  - 10
+  - 8
+cache: npm
+after_success: npx codecov --file=./coverage/lcov.info

index.js

@@ -36,12 +36,13 @@ function END(t, arg) {
 
 			// Wrap the argument expression, so that the stack trace of the assertion
 			// isn't affected.
-			path.node.arguments[0] = wrapArg(Object.assign({
+			path.node.arguments[0] = wrapArg({
 				ARG: arg0,
 				ASSERTION: t.stringLiteral(assertion),
 				FILE: t.stringLiteral(state.file.opts.filename),
-				LINE: t.numericLiteral(arg0.loc.start.line)
-			}, this.installHelper())).expression;
+				LINE: t.numericLiteral(arg0.loc.start.line),
+				...this.installHelper()
+			}).expression;
 		}
 	};