Parse type applications correctly in Node.js 12. (#1643)

Also enables CI for Node.js 12, which I had neglected to do.

.travis.yml

@@ -3,5 +3,6 @@ language: node_js
 node_js:
   - "8"
   - "10"
+  - "12"
 
 install: npm install -g gulp; npm install

lib/jsdoc/tag/type.js

@@ -11,7 +11,6 @@ const jsdoc = {
         cast: require('jsdoc/util/cast')
     }
 };
-const util = require('util');
 
 /**
  * Information about a type expression extracted from tag text.
@@ -196,9 +195,9 @@ function getTypeStrings(parsedType, isOutermostType) {
         case TYPES.TypeApplication:
             // if this is the outermost type, we strip the modifiers; otherwise, we keep them
             if (isOutermostType) {
-                applications = parsedType.applications.map(application => catharsis.stringify(application)).join(', ');
-                typeString = util.format( '%s.<%s>', getTypeStrings(parsedType.expression),
-                    applications );
+                applications = parsedType.applications.map(application =>
+                    catharsis.stringify(application)).join(', ');
+                typeString = `${getTypeStrings(parsedType.expression)[0]}.<${applications}>`;
 
                 types.push(typeString);
             }
@@ -219,8 +218,7 @@ function getTypeStrings(parsedType, isOutermostType) {
             break;
         default:
             // this shouldn't happen
-            throw new Error( util.format('unrecognized type %s in parsed type: %j', parsedType.type,
-                parsedType) );
+            throw new Error(`unrecognized type ${parsedType.type} in parsed type: ${parsedType}`);
     }
 
     return types;
@@ -247,8 +245,7 @@ function parseTypeExpression(tagInfo) {
     }
     catch (e) {
         // always re-throw so the caller has a chance to report which file was bad
-        throw new Error( util.format('Invalid type expression "%s": %s', tagInfo.typeExpression,
-            e.message) );
+        throw new Error(`Invalid type expression "${tagInfo.typeExpression}": ${e.message}`);
     }
 
     tagInfo.type = tagInfo.type.concat( getTypeStrings(parsedType, true) );