Use type-check to throw error instead of a broad try/catch

Signed-off-by: Dinika Saxena <[email protected]>

Author: Dinika

Diff for: lib/cli/options.js

@@ -110,19 +110,18 @@ const parse = (args = [], defaultValues = {}, ...configObjects) => {
   // 4. we can then reapply the values after yargs-parser is done.
   const nodeArgs = (Array.isArray(args) ? args : args.split(' ')).reduce(
     (acc, arg) => {
-      try {
-        const pair = arg.split('=');
-        let flag = pair[0];
-        if (isNodeFlag(flag, false)) {
-          flag = flag.replace(/^--?/, '');
-          return arg.includes('=')
-            ? acc.concat([[flag, pair[1]]])
-            : acc.concat([[flag, true]]);
-        }
-        return acc;
-      } catch (err) {
+      if (typeof arg !== 'string') {
         throw new Error(`Invalid option ${arg} passed to mocha cli`);
       }
+      const pair = arg.split('=');
+      let flag = pair[0];
+      if (isNodeFlag(flag, false)) {
+        flag = flag.replace(/^--?/, '');
+        return arg.includes('=')
+          ? acc.concat([[flag, pair[1]]])
+          : acc.concat([[flag, true]]);
+      }
+      return acc;
     },
     []
   );
@@ -196,7 +195,8 @@ const loadPkgRc = (args = {}) => {
           filepath
         );
       } else {
-        debug('failed to read default package.json at %s; ignoring', filepath);
+        debug('failed to read default package.json at %s; ignoring',
+              filepath);
         return result;
       }
     }

Diff for: test/node-unit/cli/options.spec.js

@@ -204,7 +204,9 @@ describe('options', function () {
             const filepath = '/some/package.json';
             readFileSync = sinon.stub();
             // package.json
-            readFileSync.onFirstCall().returns('{definitely-invalid');
+            readFileSync
+              .onFirstCall()
+              .returns('{definitely-invalid');
             findConfig = sinon.stub().returns('/some/.mocharc.json');
             loadConfig = sinon.stub().returns({});
             findupSync = sinon.stub().returns(filepath);
@@ -222,7 +224,7 @@ describe('options', function () {
                 loadOptions();
               },
               'to throw',
-              /SyntaxError/
+                /SyntaxError/,
             );
           });
         });