test: improve test coverage in a few areas

lib/rules/prefer-output-null.js

@@ -45,10 +45,9 @@ module.exports = {
             */
             function getTestInfo (key) {
               if (test.type === 'ObjectExpression') {
-                const res = test.properties.filter(item => item.key.name === key);
-                return res.length > 0 ? res[res.length - 1] : null;
+                return test.properties.find(item => item.key.name === key);
               }
-              return key === 'code' ? test : null;
+              return null;
             }
 
             const code = getTestInfo('code');

package.json

@@ -34,8 +34,8 @@
     "estraverse": "^5.2.0"
   },
   "nyc": {
-    "branches": 98,
-    "functions": 98,
+    "branches": 99,
+    "functions": 99,
     "lines": 99,
     "statements": 99
   },

tests/lib/rules/prefer-message-ids.js

@@ -104,6 +104,24 @@ ruleTester.run('prefer-message-ids', rule, {
         }
       };
     `,
+    // `meta.messages` has no static value.
+    `
+      module.exports = {
+        meta: { messages },
+        create(context) {
+          context.report({ node, messageId: FOO });
+        }
+      };
+    `,
+    // `context.report` with no args.
+    `
+      module.exports = {
+        meta: { messages },
+        create(context) {
+          context.report();
+        }
+      };
+    `,
   ],
 
   invalid: [

tests/lib/rules/prefer-output-null.js

@@ -45,7 +45,17 @@ ruleTester.run('prefer-output-null', rule, {
         invalid: []
       });
     `,
-
+    // Dynamic cases.
+    `
+      new RuleTester().run('foo', bar, {
+        valid: [
+          FOO_CASE
+        ],
+        invalid: [
+          FOO_CASE,
+        ]
+      });
+    `,
   ],
 
   invalid: [

tests/lib/rules/require-meta-schema.js

@@ -150,6 +150,23 @@ schema: []
         },
       ],
     },
+    {
+      // No `meta`, uses `context.options`. Two violations on `create`.
+      code: 'module.exports = { create(context) { const options = context.options; } };',
+      output: null,
+      errors: [
+        {
+          messageId: 'foundOptionsUsage',
+          type: 'FunctionExpression',
+          suggestions: [],
+        },
+        {
+          messageId: 'missing',
+          type: 'FunctionExpression',
+          suggestions: [],
+        },
+      ],
+    },
     {
       // requireSchemaPropertyWhenOptionless = true.
       code: `