test_tool: Let Cargo tell us where imageflow_tool resides (#650)

Fixes ‘cargo test’ with CARGO_TARGET_DIR set.

Signed-off-by: Anders Kaseorg <andersk@mit.edu>
Co-authored-by: Lilith River <lilith@imazen.io>

imageflow_tool/tests/test_tool.rs

@@ -1,55 +1,10 @@
-//#[cfg_attr(feature = "cargo-clippy", allow(useless_attribute))]
 extern crate imageflow_tool_lib;
-extern crate imageflow_types as s;
 use std::io::Write;
-use std::path::{Path,PathBuf};
-
-
-fn build_dirs() -> Vec<PathBuf>{
-    let target_triple = crate::s::version::get_build_env_value("TARGET").expect("TARGET triple required");
-    let profile = crate::s::version::get_build_env_value("PROFILE").expect("PROFILE (debug/release) required");
-
-
-    let target_dir = Path::new(env!("CARGO_MANIFEST_DIR")).parent().unwrap().join("target");
-
-    let a = target_dir.join(target_triple).join(profile);
-    let b = target_dir.join(profile);
-    vec![a,b]
-}
-#[cfg(windows)]
-fn binary_ext() -> &'static str{
-    "exe"
-}
-#[cfg(not(windows))]
-fn binary_ext() -> &'static str{
-    ""
-}
-
-fn locate_binary(name: &str) -> Option<PathBuf> {
-    for dir in build_dirs() {
-        let file_path = dir.join(name).with_extension(binary_ext());
-
-        if file_path.exists() {
-            return Some(dir.join(name))
-        }
-    }
-    None
-}
-
-
-fn tool_path() -> PathBuf {
-    match locate_binary("imageflow_tool"){
-        Some(v) => v,
-        None => {
-            panic!("Failed to locate imageflow_tool binary in {:?}", build_dirs());
-        }
-    }
-}
-
+use std::path::PathBuf;
 
 #[test]
 fn run_imageflow_tool_self_test(){
-    let tool = tool_path();
+    let tool = PathBuf::from(env!("CARGO_BIN_EXE_imageflow_tool"));
     let _  = writeln!(std::io::stdout(), "Testing binary {:?}", &tool);
     imageflow_tool_lib::self_test::run(Some(tool.clone()));
     imageflow_tool_lib::self_test::test_capture(Some(tool));