move one snapshot/add test into testsuite/cargo_add/

tests/testsuite/cargo_add.rs

@@ -2,6 +2,8 @@ use cargo_test_support::compare::assert;
 use cargo_test_support::prelude::*;
 use cargo_test_support::Project;
 
+mod build_prefer_existing_version;
+
 fn init_registry() {
     cargo_test_support::registry::init();
     add_registry_packages(false);
@@ -202,28 +204,6 @@ fn build() {
     assert().subset_matches("tests/snapshots/add/build/out", &project_root);
 }
 
-#[cargo_test]
-fn build_prefer_existing_version() {
-    init_alt_registry();
-    let project = Project::from_template("tests/snapshots/add/build_prefer_existing_version/in");
-    let project_root = project.root();
-    let cwd = &project_root;
-
-    snapbox::cmd::Command::cargo()
-        .arg("add")
-        .arg_line("cargo-list-test-fixture-dependency --build")
-        .current_dir(cwd)
-        .assert()
-        .success()
-        .stdout_matches_path("tests/snapshots/add/build_prefer_existing_version/stdout.log")
-        .stderr_matches_path("tests/snapshots/add/build_prefer_existing_version/stderr.log");
-
-    assert().subset_matches(
-        "tests/snapshots/add/build_prefer_existing_version/out",
-        &project_root,
-    );
-}
-
 #[cargo_test]
 fn default_features() {
     init_registry();

tests/testsuite/cargo_add/build_prefer_existing_version/mod.rs

@@ -0,0 +1,28 @@
+use cargo_test_support::compare::assert;
+use cargo_test_support::prelude::*;
+use cargo_test_support::Project;
+
+use crate::cargo_add::init_alt_registry;
+
+#[cargo_test]
+fn build_prefer_existing_version() {
+    init_alt_registry();
+    let project =
+        Project::from_template("tests/testsuite/cargo_add/build_prefer_existing_version/in");
+    let project_root = project.root();
+    let cwd = &project_root;
+
+    snapbox::cmd::Command::cargo()
+        .arg("add")
+        .arg_line("cargo-list-test-fixture-dependency --build")
+        .current_dir(cwd)
+        .assert()
+        .success()
+        .stdout_matches_path("tests/testsuite/cargo_add/build_prefer_existing_version/stdout.log")
+        .stderr_matches_path("tests/testsuite/cargo_add/build_prefer_existing_version/stderr.log");
+
+    assert().subset_matches(
+        "tests/testsuite/cargo_add/build_prefer_existing_version/out",
+        &project_root,
+    );
+}