Add tests for using worktrees and sparse checkouts

tests/testsuite/git.rs

@@ -12,7 +12,9 @@ use std::thread;
 use cargo_test_support::git::cargo_uses_gitoxide;
 use cargo_test_support::paths::{self, CargoPathExt};
 use cargo_test_support::registry::Package;
-use cargo_test_support::{basic_lib_manifest, basic_manifest, git, main_file, path2url, project};
+use cargo_test_support::{
+    basic_lib_manifest, basic_manifest, git, git_process, main_file, path2url, project,
+};
 use cargo_test_support::{sleep_ms, t, Project};
 
 #[cargo_test]
@@ -3760,3 +3762,90 @@ fn different_user_relative_submodules() {
 
     assert!(project.bin("foo").is_file());
 }
+
+#[cargo_test(requires_git)]
+fn cargo_package_with_new_worktree() {
+    let project = project().build();
+    let git_project = git::new("foo", |project| {
+        project.file("src/lib.rs", "").file("README.md", "").file(
+            "Cargo.toml",
+            &format!(
+                r#"[package]
+name = "foo"
+version = "0.1.0"
+edition = "2015"
+authors = []
+license = "MIR OR Apache-2.0"
+description = "A test!"
+homepage = "https://example.org"
+documentation = ""
+repository = "https://example.org"
+readme = "./README.md"
+"#,
+            ),
+        )
+    });
+
+    let repo = git2::Repository::open(&git_project.root()).unwrap();
+    let repo_root = repo.workdir().unwrap().parent().unwrap();
+    let opts = git2::WorktreeAddOptions::new();
+    let wt = repo
+        .worktree("bar", &repo_root.join("bar"), Some(&opts))
+        .unwrap();
+
+    project
+        .cargo("package --list")
+        .cwd(wt.path())
+        .with_stdout(
+            "\
+.cargo_vcs_info.json
+Cargo.toml
+Cargo.toml.orig
+README.md
+src/lib.rs
+",
+        )
+        .run();
+}
+
+#[cargo_test(requires_git)]
+fn cargo_check_with_sparse_checkouts() {
+    let git_project = git::new("foo", |project| {
+        project.file("src/lib.rs", "").file(
+            "Cargo.toml",
+            &format!(
+                r#"
+[package]
+name = "foo"
+version = "0.5.0"
+edition = "2015"
+authors = []
+"#,
+            ),
+        )
+    });
+
+    let path = git_project.root();
+    git_process("sparse-checkout init")
+        .cwd(&path)
+        .exec()
+        .unwrap();
+    let output = git_process("config core.sparseCheckout")
+        .cwd(&path)
+        .exec_with_output()
+        .unwrap();
+    assert!(output.stdout.starts_with(b"true"));
+    git_process("sparse-checkout add src")
+        .cwd(&path)
+        .exec()
+        .unwrap();
+    git_project
+        .cargo("check")
+        .with_stderr(&format!(
+            "[CHECKING] foo v0.5.0 ([CWD])\n\
+         [FINISHED] `dev` profile [unoptimized + debuginfo] target(s) \
+         in [..]\n"
+        ))
+        .run();
+}
+\