Fix false negative for ref in vue/script-setup-uses-vars rule. (#1547)

Author: ota-meshi

lib/rules/script-setup-uses-vars.js

@@ -104,6 +104,12 @@ module.exports = {
             return
           }
           markElementVariableAsUsed(`v-${node.key.name.rawName}`)
+        },
+        /** @param {VAttribute} node */
+        'VAttribute[directive=false]'(node) {
+          if (node.key.name === 'ref' && node.value) {
+            context.markVariableAsUsed(node.value.value)
+          }
         }
       },
       undefined,

tests/lib/rules/script-setup-uses-vars.js

@@ -163,6 +163,22 @@ describe('script-setup-uses-vars', () => {
           ecmaVersion: 2022,
           sourceType: 'module'
         }
+      },
+
+      // ref
+      {
+        filename: 'test.vue',
+        code: `
+        <script setup>
+          /* eslint script-setup-uses-vars: 1 */
+          import {ref} from 'vue'
+          const v = ref(null)
+        </script>
+
+        <template>
+          <div ref="v"/>
+        </template>
+        `
       }
     ],