Auto merge of #11145 - hi-rustin:rustin-patch-login, r=weihanglo

Check empty input for login

### What does this PR try to resolve?

close #11144
Check empty input for login.

### How should we test and review this PR?

- unit test
- cargo login and enter

src/cargo/ops/registry.rs

@@ -768,6 +768,10 @@ pub fn registry_login(
         }
     };
 
+    if token.is_empty() {
+        bail!("please provide a non-empty token");
+    }
+
     if let RegistryConfig::Token(old_token) = &reg_cfg {
         if old_token == &token {
             config.shell().status("Login", "already logged in")?;

tests/testsuite/login.rs

@@ -90,3 +90,31 @@ fn registry_credentials() {
     assert!(check_token(TOKEN, Some(reg)));
     assert!(check_token(TOKEN2, Some(reg2)));
 }
+
+#[cargo_test]
+fn empty_login_token() {
+    let _registry = RegistryBuilder::new().build();
+    setup_new_credentials();
+
+    cargo_process("login")
+        .with_stdout("please paste the API Token found on [..]/me below")
+        .with_stdin("\t\n")
+        .with_stderr(
+            "\
+[UPDATING] `dummy-registry` index
+[ERROR] please provide a non-empty token
+",
+        )
+        .with_status(101)
+        .run();
+
+    cargo_process("login")
+        .arg("")
+        .with_stderr(
+            "\
+[ERROR] please provide a non-empty token
+",
+        )
+        .with_status(101)
+        .run();
+}