fix: getSigned(Policy|Url) throws if expiration is invalid Date (#614)

src/file.ts

@@ -2045,6 +2045,10 @@ class File extends ServiceObject<File> {
     const callback = args.callback;
     const expires = new Date((options as GetSignedPolicyOptions).expires);
 
+    if (isNaN(expires.getTime())) {
+      throw new Error('The expiration date provided was invalid.');
+    }
+
     if (expires.valueOf() < Date.now()) {
       throw new Error('An expiration date cannot be in the past.');
     }
@@ -2262,6 +2266,10 @@ class File extends ServiceObject<File> {
       void|Promise<GetSignedUrlResponse> {
     const expiresInMSeconds = new Date(cfg.expires).valueOf();
 
+    if (isNaN(expiresInMSeconds)) {
+      throw new Error('The expiration date provided was invalid.');
+    }
+
     if (expiresInMSeconds < Date.now()) {
       throw new Error('An expiration date cannot be in the past.');
     }

test/file.ts

@@ -2146,6 +2146,18 @@ describe('File', () => {
             });
       });
 
+      it('should throw if a date is invalid', () => {
+        const expires = new Date('31-12-2019');
+
+        assert.throws(() => {
+          file.getSignedPolicy(
+              {
+                expires,
+              },
+              () => {});
+        }, /The expiration date provided was invalid\./);
+      });
+
       it('should throw if a date from the past is given', () => {
         const expires = Date.now() - 5;
 
@@ -2554,6 +2566,19 @@ describe('File', () => {
             });
       });
 
+      it('should throw if a date is invalid', () => {
+        const expires = new Date('31-12-2019');
+
+        assert.throws(() => {
+          file.getSignedUrl(
+              {
+                action: 'read',
+                expires,
+              },
+              () => {});
+        }, /The expiration date provided was invalid\./);
+      });
+
       it('should throw if a date from the past is given', () => {
         const expires = Date.now() - 5;