feat: Validate cli flags

.flowconfig

@@ -1,5 +1,7 @@
 [ignore]
 .*/.nyc_output/.*
+.*/coverage/.*
+.*/fixtures/.*
 .*/.vscode/.*
 .*/assets/.*
 .*/node_modules/.*

cli.js

@@ -2,16 +2,50 @@
 /* @flow */
 
 const meow = require("meow");
+const chalk = require("chalk");
 const defaultCommand = require("./commands/default");
 const byCommand = require("./commands/by");
 const helpCommand = require("./commands/help");
+const knownFlags = [
+  "by",
+  "modulesOnly",
+  "filesOnly",
+  "directOnly",
+  "transitiveOnly",
+  "duplicatesOnly",
+  "limit",
+  "version",
+  "help"
+];
+
+const validateFlags = flags => {
+  const invalidFlags = Object.keys(flags).reduce((acc, flag) => {
+    if (!knownFlags.includes(flag)) {
+      acc.push(flag);
+    }
+    return acc;
+  }, []);
+
+  return invalidFlags;
+};
 
 const { pkg, input, flags, showHelp } = meow(helpCommand(), {
   argv: process.argv.slice(2),
   autoHelp: false
 });
 
 const start = Date.now();
+const invalidFlags = validateFlags(flags);
+
+if (invalidFlags.length) {
+  console.log();
+  console.log(chalk.red(`  Unsupported option: ${invalidFlags.join(", ")}`));
+  console.log();
+  console.log(
+    `  Use ${chalk.yellow("--help")} to see a list of available options...`
+  );
+  process.exit(1);
+}
 
 if (!input || !input.length || !input[0].match(".json") || flags.help) {
   showHelp(0);

package.json

@@ -26,8 +26,7 @@
   },
   "pre-commit": [
     "lint:flow",
-    "lint:staged",
-    "test"
+    "lint:staged"
   ],
   "lint-staged": {
     "*.js": [