test: add test for install with dry-run option

Author: Flowrey

tests/testsuite/cargo_install/help/stdout.term.svg

@@ -2730,3 +2730,20 @@ fn uninstall_running_binary() {
 
 "#]]).run();
 }
+
+#[cargo_test]
+fn dry_run() {
+    pkg("foo", "0.0.1");
+
+    cargo_process("-Z unstable-options install --dry-run foo")
+        .masquerade_as_nightly_cargo(&["install::dry-run"])
+        .with_stderr_data(str![[r#"
+[UPDATING] `dummy-registry` index
+[DOWNLOADING] crates ...
+[DOWNLOADED] foo v0.0.1 (registry `dummy-registry`)
+[INSTALLING] foo v0.0.1
+
+"#]])
+        .run();
+    assert_has_not_installed_exe(paths::cargo_home(), "foo");
+}