Add linter for naked console.errors

Summary:
`console.error(err)` are hard to identify in the codebase especially
as we often don't have reliable stack trace information.

I've already cleaned up a bunch of them manually by going after the most
high-firing ones; this should make it easier to identify the remaining ones.

Reviewed By: jknoxville

Differential Revision: D27913964

fbshipit-source-id: 0ff6624a0c083829846550b40954945d655b7cf6

desktop/eslint-plugin-flipper/src/rules/__tests__/noConsoleErrorWithoutContext.node.ts

@@ -0,0 +1,52 @@
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @format
+ */
+
+import {TSESLint} from '@typescript-eslint/experimental-utils';
+import rule, {RULE_NAME} from '../noConsoleErrorWithoutContext';
+
+const tester = new TSESLint.RuleTester({
+  parser: require.resolve('@typescript-eslint/parser'),
+  parserOptions: {
+    sourceType: 'module',
+    ecmaVersion: 2020,
+  },
+});
+
+tester.run(RULE_NAME, rule, {
+  valid: [
+    {
+      code: `console.error("I've made a big mistake:", err);`,
+      filename: __filename,
+    },
+    {
+      code: `console.error("This should never happen.");`,
+      filename: __filename,
+    },
+    {
+      code: `console.error("Failed to open user settings: " + err);`,
+      filename: __filename,
+    },
+    {
+      code: `console.warn(e);`,
+      filename: __filename,
+    },
+  ],
+  invalid: [
+    {
+      code: `console.error(err);`,
+      filename: __filename,
+      errors: [{messageId: 'noConsoleErrorWithoutContext'}],
+    },
+    {
+      code: `console.error(err, "Too late for context.");`,
+      filename: __filename,
+      errors: [{messageId: 'noConsoleErrorWithoutContext'}],
+    },
+  ],
+});