You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: rustdoc_extern_html.rs
    path of file: ./repos/cargo/tests/testsuite
    
    the code of the file until where you have to start completion: //! Tests for the -Zrustdoc-map feature.

use cargo_test_support::registry::{self, Package};
use cargo_test_support::{paths, project, Project};

fn basic_project() -> Project {
    Package::new("bar", "1.0.0")
        .file("src/lib.rs", "pub struct Straw;")
        .publish();

    project()
        .file(
            "Cargo.toml",
            r#"
                [package]
                name = "foo"
                version = "0.1.0"
                edition = "2018"

                [dependencies]
                bar = "1.0"
            "#,
        )
        .file(
          
    
fn std_docs() {
    // Mapping std docs somewhere else.
    // For local developers, skip this test if docs aren't installed.
    let docs = std::path::Path::new(&paths::sysroot()).join("share/doc/rust/html");
    if !docs.exists() {
        if cargo_util::is_ci() {
            panic!("std docs are not installed, check that the rust-docs component is installed");
        } else {
            eprintln!(
                "documentation not found at {}, \
                skipping test (run `rustdoc component add rust-docs` to install",
                docs.display()
            );
            return;
        }
    }
    let p = basic_project();
    p.change_file(
        ".cargo/config.toml",
        r#"
            [doc.extern-map]
            std = "local"
        "#,
    );
    p.cargo("doc -v --no-deps -Zrustdoc-map")
        .masquerade_as_nightly_cargo(&["rustdoc-map"])
        .with_stderr_contains("[RUNNING] `rustdoc [..]--crate-name foo [..]std=file://[..]")
        .run();
    let myfun = p.read_file("target/doc/foo/fn.myfun.html");
    assert!(myfun.contains(r#"share/doc/rust/html/core/option/enum.Option.html""#));

    p.change_file(
        ".cargo/config.toml",
        r#"
            [doc.extern-map]
            std = "https://example.com/rust/"
        "#,
    );
    p.cargo("doc -v --no-deps -Zrustdoc-map")
        .masquerade_as_nightly_cargo(&["rustdoc-map"])
        .with_stderr_contains(
            "[RUNNING] `rustdoc [..]--crate-name foo [..]std=https://example.com/rust/[..]",
        )
        .run();
    let myfun = p.read_file("target/doc/foo/fn.myfun.html");
    assert!(myfun.contains(r#"href="https://example.com/rust/core/option/enum.Option.html""#));
}