bin/repl: handle missing should dependency (#1229)

Dev dependencies are not available in production environments.

lib/bin/repl.js

@@ -7,18 +7,23 @@
 // including this file, may be copied, modified, propagated, or distributed
 // except according to the terms contained in the LICENSE file.
 
-const should = require('should'); // eslint-disable-line import/no-extraneous-dependencies
-require('../../test/assertions');
-
 const _ = require('lodash'); // eslint-disable-line import/no-extraneous-dependencies
 const { sql } = require('slonik');
 
 const container = require('../util/default-container');
 
 (async () => {
-  const context = { ..._.omit(container, 'with'), container, should, sql };
-  const contextKeys = Object.keys(context).sort();
-  console.log('Available vars:', contextKeys.join(', '));
+  const context = { ..._.omit(container, 'with'), container, sql };
+  const replGlobals = Object.keys(context);
+
+  try {
+    // should adds itself directly to global scope, so does not need to be added to the context
+    require('should'); // eslint-disable-line import/no-extraneous-dependencies
+    require('../../test/assertions');
+    replGlobals.push('should');
+  } catch (err) { /* skip devDependencies if unavailable */ }
+
+  console.log('Available vars:', replGlobals.sort().join(', '));
 
   const repl = require('repl').start({
     useGlobal: true, // enable should.js prototype pollution