Test the passing of --error-format to rustdoc

tests/testsuite/message_format.rs

@@ -1,6 +1,6 @@
 //! Tests for --message-format flag.
 
-use cargo_test_support::{basic_manifest, project};
+use cargo_test_support::{basic_lib_manifest, basic_manifest, is_nightly, project};
 
 #[cargo_test]
 fn cannot_specify_two() {
@@ -109,3 +109,30 @@ fn cargo_renders_ansi() {
         .with_stdout_contains("[..]\\u001b[38;5;9merror[..]")
         .run();
 }
+
+#[cargo_test]
+fn cargo_renders_doctests() {
+    if !is_nightly() {
+        // --error-format=short support added in 1.51
+        return;
+    }
+
+    let p = project()
+        .file("Cargo.toml", &basic_lib_manifest("foo"))
+        .file(
+            "src/lib.rs",
+            "\
+            /// ```rust
+            /// bar()
+            /// ```
+            pub fn bar() {}
+            ",
+        )
+        .build();
+
+    p.cargo("test --doc --message-format short")
+        .with_status(101)
+        .with_stdout_contains("src/lib.rs:2:1: error[E0425]:[..]")
+        .with_stdout_contains("[..]src/lib.rs - bar (line 1)[..]")
+        .run();
+}