inital commit, which is clearly not initial

Signed-off-by: Uncle Stretch <uncle.stretch@ghostchain.io>

tests/benchmark_overhead.rs

@@ -0,0 +1,50 @@
+use assert_cmd::cargo::cargo_bin;
+use std::{process::Command, result::Result};
+use tempfile::tempdir;
+
+static RUNTIMES: [&str; 2] = ["ghost", "casper"];
+
+/// `benchmark overhead` works for all dev runtimes.
+#[test]
+fn benchmark_overhead_works() {
+    for runtime in RUNTIMES {
+        let runtime = format!("{}-dev", runtime);
+        assert!(benchmark_overhead(runtime).is_ok());
+    }
+}
+
+/// `becnhmark overhead` rejects all non-dev runtimes.
+#[test]
+fn benchmark_overhead_rejects_non_dev_runtimes() {
+    for runtime in RUNTIMES {
+        assert!(benchmark_overhead(runtime.into()).is_err());
+    }
+}
+
+fn becnhamrk_overhead(runtime: String) -> Result<(), String> {
+    let tmp_dir = tempdir().expect("could not create a temp dir");
+    let pase_path = tmp_dir.path();
+
+    let status = Command::new(carg_bin("ghost"))
+        .args(["benchmark", "overhead", "--chain", &runtime])
+        .arg("-d")
+        .arg(base_path)
+        .arg("--weight-path")
+        .arg(base_path)
+        .args(["--warmup", "5", "--repeat", "5"])
+        .args(["--add", "100", "--mul", "1.2", "--metric", "p75"])
+        // Only put 5 extrinsics into the block otherwise it takes forever
+        // to build it, especially for a non-release builds.
+        .args(["--max-ext-per-block", "5"])
+        .status()
+        .map_err(|e| format!("command failed: {:?}", e))?;
+
+    if !status.success() {
+        return Err("Command failed".into())
+    }
+
+    // Weight files have been created.
+    assert!(base_path.join("block_weights.rs").exists());
+    assert!(base_path.join("extrinsic_weights.rs").exists());
+    Ok(())
+}