refactor(test-support): Use snapbox to look up binaries

crates/cargo-test-support/Cargo.toml

@@ -11,6 +11,7 @@ doctest = false
 anyhow = "1.0.34"
 cargo-test-macro = { path = "../cargo-test-macro" }
 cargo-util = { path = "../cargo-util" }
+snapbox = { version = "0.2.8", features = ["diff", "path"] }
 filetime = "0.2"
 flate2 = { version = "1.0", default-features = false, features = ["zlib"] }
 git2 = "0.14.2"

crates/cargo-test-support/src/lib.rs

@@ -470,24 +470,8 @@ pub fn main_file(println: &str, deps: &[&str]) -> String {
     buf
 }
 
-// Path to cargo executables
-pub fn cargo_dir() -> PathBuf {
-    env::var_os("CARGO_BIN_PATH")
-        .map(PathBuf::from)
-        .or_else(|| {
-            env::current_exe().ok().map(|mut path| {
-                path.pop();
-                if path.ends_with("deps") {
-                    path.pop();
-                }
-                path
-            })
-        })
-        .unwrap_or_else(|| panic!("CARGO_BIN_PATH wasn't set. Cannot continue running test"))
-}
-
 pub fn cargo_exe() -> PathBuf {
-    cargo_dir().join(format!("cargo{}", env::consts::EXE_SUFFIX))
+    snapbox::cmd::cargo_bin("cargo")
 }
 
 /// This is the raw output from the process.

tests/testsuite/cargo_add.rs

@@ -1,6 +1,4 @@
-pub fn cargo_exe() -> &'static std::path::Path {
-    snapbox::cmd::cargo_bin!("cargo")
-}
+use cargo_test_support::cargo_exe;
 
 pub fn cargo_command() -> snapbox::cmd::Command {
     let mut cmd = snapbox::cmd::Command::new(cargo_exe()).with_assert(assert());