fix: a bug where a reference to an missing variable in PowerShell would cause an exception

src/util/coerce-option.ts

@@ -17,7 +17,11 @@ import {readFileSync, statSync, Stats} from 'fs';
 // if an option looks like a file path, assume it's a
 // path to a key and load it.
 export function coerceOption(option: string): string {
-  if (option.match(/[\\/]/)) {
+  // Only check .match if option is a string, to avoid TypeError.
+  // This might happen if the user didn't pass any payload for
+  // the option, or if the payload is empty. Example:
+  // --token $EMPTY_VAR
+  if (typeof option === 'string' && option.match(/[\\/]/)) {
     try {
       const stat: Stats = statSync(option);
       if (stat.isDirectory()) return option;

test/util/coerce-option.ts

@@ -38,4 +38,11 @@ describe('coerceOption', () => {
     const coerced = coerceOption(resolve(fixturesPath, 'key.txt'));
     expect(coerced).to.equal('abc123');
   });
+  it('should not throw when a non-string value is passed', () => {
+    expect(() => coerceOption(undefined as unknown as string)).not.to.Throw();
+    expect(() => coerceOption(null as unknown as string)).not.to.Throw();
+    expect(() => coerceOption(123 as unknown as string)).not.to.Throw();
+    expect(() => coerceOption({} as unknown as string)).not.to.Throw();
+    expect(() => coerceOption([] as unknown as string)).not.to.Throw();
+  });
 });