Only add commas if there is a concrete default value in annotated plugins. Only show field name and type if there is no default.

packages/coreutils/src/settingregistry.ts

@@ -1306,7 +1306,7 @@ export namespace Private {
       prefix(description || nondescript),
       prefix(line(length)),
       '',
-      keys.map(key => defaultDocumentedValue(schema, key)).join(',\n\n'),
+      join(keys.map(key => defaultDocumentedValue(schema, key))),
       '}'
     ].join('\n');
   }
@@ -1333,9 +1333,7 @@ export namespace Private {
       prefix(description || nondescript),
       prefix(line(length)),
       '',
-      keys
-        .map(key => documentedValue(plugin.schema, key, data[key]))
-        .join(',\n\n'),
+      join(keys.map(key => documentedValue(plugin.schema, key, data[key]))),
       '}'
     ].join('\n');
   }
@@ -1348,21 +1346,18 @@ export namespace Private {
     schema: ISettingRegistry.ISchema,
     key: string
   ): string {
-    const props = schema.properties && schema.properties[key];
-    const description = (props && props['description']) || nondescript;
-    const title = (props && props['title']) || untitled;
+    const props = (schema.properties && schema.properties[key]) || {};
+    const type = props['type'];
+    const description = props['description'] || nondescript;
+    const title = props['title'] || '';
     const reified = reifyDefault(schema, key);
     const spaces = indent.length;
     const defaults =
       reified !== undefined
         ? prefix(`"${key}": ${JSON.stringify(reified, null, spaces)}`, indent)
-        : '';
+        : prefix(`"${key}": ${type}`);
 
-    return [
-      prefix(`${title || untitled}`),
-      prefix(description || nondescript),
-      defaults
-    ]
+    return [prefix(title), prefix(description), defaults]
       .filter(str => str.length)
       .join('\n');
   }
@@ -1386,6 +1381,22 @@ export namespace Private {
 
     return [prefix(title), prefix(description), attribute].join('\n');
   }
+
+  /**
+   * Returns a joined string with line breaks and commas where appropriate.
+   */
+  function join(body: string[]): string {
+    return body.reduce((acc, val, idx) => {
+      const rows = val.split('\n');
+      const last = rows[rows.length - 1];
+      const comment = last.trim().indexOf('//') === 0;
+      const comma = comment || idx === body.length - 1 ? '' : ',';
+      const separator = idx === body.length - 1 ? '' : '\n\n';
+
+      return acc + val + comma + separator;
+    }, '');
+  }
+
   /**
    * Returns a line of a specified length.
    */
@@ -1396,7 +1407,7 @@ export namespace Private {
   /**
    * Returns a documentation string with a comment prefix added on every line.
    */
-  function prefix(source: string, pre = `${indent}\/\/ `): string {
+  function prefix(source: string, pre = `${indent}// `): string {
     return pre + source.split('\n').join(`\n${pre}`);
   }