Enable prefer-const in the eslint config

.eslintrc.yml

@@ -12,3 +12,4 @@ rules:
   eqeqeq: error
   no-warning-comments: warn
   no-var: error
+  prefer-const: error

samples/document-snippets/instance.js

@@ -50,7 +50,7 @@ const snippets = {
     instance
       .create(options)
       .then(result => {
-        let newInstance = result[0];
+        const newInstance = result[0];
         // let operations = result[1];
         // let apiResponse = result[2];
 
@@ -269,7 +269,7 @@ const snippets = {
       .getTables(options)
       .then(result => {
         console.log(`Tables:`);
-        let tables = result[0];
+        const tables = result[0];
         tables.forEach(t => {
           console.log(t.id);
         });
@@ -286,7 +286,7 @@ const snippets = {
     const instance = bigtable.instance(instanceId);
 
     // [START bigtable_set_meta_data]
-    let metadata = {
+    const metadata = {
       displayName: 'updated-name',
     };
 

samples/document-snippets/test.js

@@ -30,7 +30,7 @@ const instanceSnippets = require('./instance.js');
 
 describe('Instance Snippets', function() {
   after(function(done) {
-    let instance = bigtable.instance(INSTANCE_ID);
+    const instance = bigtable.instance(INSTANCE_ID);
     instance.delete(done);
   });
 

samples/hello-world/index.js

@@ -26,7 +26,7 @@ if (!GCLOUD_PROJECT) {
   throw new Error('Environment variables GCLOUD_PROJECT must be set!');
 }
 
-let bigtableOptions = {
+const bigtableOptions = {
   projectId: GCLOUD_PROJECT,
 };
 
@@ -83,7 +83,7 @@ const getRowGreeting = row => {
     ];
 
     console.log('Reading a single row by row key');
-    let [singeRow] = await table.row('greeting0').get({filter});
+    const [singeRow] = await table.row('greeting0').get({filter});
     console.log(`\tRead: ${getRowGreeting(singeRow)}`);
 
     console.log('Reading the entire table');

samples/hello-world/index.v6.js

@@ -28,7 +28,7 @@ if (!GCLOUD_PROJECT) {
   throw new Error('Environment variables GCLOUD_PROJECT must be set!');
 }
 
-let bigtableOptions = {
+const bigtableOptions = {
   projectId: GCLOUD_PROJECT,
 };
 
@@ -87,7 +87,7 @@ co(function*() {
     ];
 
     console.log('Reading a single row by row key');
-    let [singeRow] = yield table.row('greeting0').get({filter});
+    const [singeRow] = yield table.row('greeting0').get({filter});
     console.log(`\tRead: ${getRowGreeting(singeRow)}`);
 
     console.log('Reading the entire table');

samples/instances.js

@@ -23,7 +23,7 @@ if (!GCLOUD_PROJECT) {
   throw new Error('Environment variables GCLOUD_PROJECT must be set!');
 }
 
-let bigtableOptions = {
+const bigtableOptions = {
   projectId: GCLOUD_PROJECT,
 };
 
@@ -142,7 +142,7 @@ async function createDevInstance(instanceID, clusterID) {
 
   // Create development instance with given options
   try {
-    let [instance] = await bigtable.createInstance(instanceID, options);
+    const [instance] = await bigtable.createInstance(instanceID, options);
     console.log(`Created development instance: ${instance.id}`);
   } catch (err) {
     console.error('Error creating dev-instance:', err);

samples/quickstart.js

@@ -31,7 +31,7 @@ if (!GCLOUD_PROJECT) {
 
 (async () => {
   try {
-    let bigtableOptions = {
+    const bigtableOptions = {
       projectId: GCLOUD_PROJECT,
     };
 
@@ -46,7 +46,7 @@ if (!GCLOUD_PROJECT) {
     const table = instance.table(TABLE_ID);
 
     // Read a row from my-table using a row key
-    let [singleRow] = await table.row('r1').get();
+    const [singleRow] = await table.row('r1').get();
 
     // Print the row key and data (column value, labels, timestamp)
     console.log(

samples/tableadmin.js

@@ -23,7 +23,7 @@ if (!GCLOUD_PROJECT) {
   throw new Error('Environment variables GCLOUD_PROJECT must be set!');
 }
 
-let bigtableOptions = {
+const bigtableOptions = {
   projectId: GCLOUD_PROJECT,
 };
 
@@ -62,7 +62,7 @@ async function runTableOperations(instanceID, tableID) {
   // [START bigtable_list_tables]
   // List tables in current project
   try {
-    let [tables] = await instance.getTables();
+    const [tables] = await instance.getTables();
     tables.forEach(table => {
       console.log(table.id);
     });