src: add --pending-deprecation and NODE_PENDING_DEPRECATION

Command line flag and environment variable that can be used to
indicate that pending deprecations should be emitted.

PR-URL: https://github.com/nodejs/node/pull/11968
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: Michael Dawson <michael_dawson@ca.ibm.com>
Reviewed-By: Сковорода Никита Андреевич <chalkerx@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

1 files changed, 45 insertions, 0 deletions

diff --git a/test/parallel/test-pending-deprecation.js b/test/parallel/test-pending-deprecation.js
new file mode 100644
index 0000000000..402ec79b1b
--- /dev/null
+++ b/test/parallel/test-pending-deprecation.js
@@ -0,0 +1,45 @@
+'use strict';
+
+// Tests that --pending-deprecation and NODE_PENDING_DEPRECATION both
+// set the process.binding('config').pendingDeprecation flag that is
+// used to determine if pending deprecation messages should be shown.
+// The test is performed by launching two child processes that run
+// this same test script with different arguments. If those exit with
+// code 0, then the test passes. If they don't, it fails.
+
+const common = require('../common');
+
+const assert = require('assert');
+const config = process.binding('config');
+const fork = require('child_process').fork;
+
+function message(name) {
+  return `${name} did not set the process.binding('config').` +
+         'pendingDeprecation flag.';
+}
+
+switch (process.argv[2]) {
+  case 'env':
+  case 'switch':
+    assert.strictEqual(config.pendingDeprecation, true);
+    break;
+  default:
+    // Verify that the flag is off by default.
+    assert.strictEqual(config.pendingDeprecation, undefined);
+
+    // Test the --pending-deprecation command line switch.
+    fork(__filename, ['switch'], {
+      execArgv: ['--pending-deprecation'],
+      silent: true
+    }).on('exit', common.mustCall((code) => {
+      assert.strictEqual(code, 0, message('--pending-deprecation'));
+    }));
+
+    // Test the NODE_PENDING_DEPRECATION environment var.
+    fork(__filename, ['env'], {
+      env: {NODE_PENDING_DEPRECATION: 1},
+      silent: true
+    }).on('exit', common.mustCall((code) => {
+      assert.strictEqual(code, 0, message('NODE_PENDING_DEPRECATION'));
+    }));
+}