Instead of testing process.version, use a canary ES6 file.

Author: mikesamuel

test/README.md

@@ -0,0 +1,12 @@
+# Unit tests for sqlstring
+
+## Running tests on older node versions
+
+We rely on Travis CI to check compatibility with older Node runtimes.
+
+To locally run tests on an older runtime, for example `0.12`:
+
+```sh
+$ npm install --no-save npx
+$ ./node_modules/.bin/npx node@0.12 test/run.js
+```

test/unit/es6/canary.js

@@ -0,0 +1,3 @@
+// A minimal file that uses ES6 features which will fail to load on
+// older browsers.
+`I load on ES6`;

test/unit/test-Lexer.js

@@ -1,7 +1,12 @@
-// If we're on a Node runtime that should support ES6, run the ES6 tests.
-if (/^v?[0-5][.]/.test(process.version)) {
-  // The major version is a single digit in [0, 5].
-  console.info('Skipping ES6 tests for node_version %s', process.version);
-} else {
+var canRequireES6 = true;
+try {
+  require('./es6/canary');
+} catch (ignored) {
+  canRequireES6 = false;
+}
+
+if (canRequireES6) {
   require('./es6/Lexer');
+} else {
+  console.info('Skipping ES6 tests for node_version %s', process.version);
 }

test/unit/test-Template.js

@@ -2,9 +2,16 @@ var assert    = require('assert');
 var SqlString = require('../../');
 var test      = require('utest');
 
-// If we're on a Node runtime that should support ES6, run the ES6 tests.
-if (/^v?[0-5][.]/.test(process.version)) {
-  // The major version is a single digit in [0, 5].
+var canRequireES6 = true;
+try {
+  require('./es6/canary');
+} catch (ignored) {
+  canRequireES6 = false;
+}
+
+if (canRequireES6) {
+  require('./es6/Template');
+} else {
   console.info('Skipping ES6 tests for node_version %s', process.version);
 
   test('Template fallback', {
@@ -17,8 +24,6 @@ if (/^v?[0-5][.]/.test(process.version)) {
         });
     }
   });
-} else {
-  require('./es6/Template');
 }
 
 var sql = SqlString.sql;