From 4dfcdb1a82b318c1fd018718278caea587193a25 Mon Sep 17 00:00:00 2001
From: Ian Jackson <ijackson@chiark.greenend.org.uk>
Date: Wed, 6 Jan 2021 00:32:01 +0000
Subject: [PATCH] ensure_eq, fix

Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>
---
 src/utils.rs          | 17 +++++++++++++++++
 wdriver.rs            |  1 +
 wdriver/wdt-simple.rs |  4 ++--
 3 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/src/utils.rs b/src/utils.rs
index 69a651bc..378d843a 100644
--- a/src/utils.rs
+++ b/src/utils.rs
@@ -11,6 +11,23 @@ use std::os::unix::io::IntoRawFd;
 use fehler::{throw, throws};
 use libc;
 
+#[macro_export]
+macro_rules! ensure_eq {
+  ($v1:expr, $v2:expr) => {
+    ({
+      let v1 = $v1;
+      let v2 = $v2;
+      if &v1 != &v2 {
+        Err(anyhow!("ensure_eq failed: {} != {}: {:?} != {:?}",
+                    stringify!($v1), stringify!($v2),
+                    &v1, &v2))
+      } else {
+        Ok(())
+      }
+    }?)
+  }
+}
+
 pub trait OrdExt: Ord + Sized + Clone {
   fn update_max(&mut self, new: &Self) {
     if *new > *self { *self = new.clone() }
diff --git a/wdriver.rs b/wdriver.rs
index 2ba265b2..11ca44c4 100644
--- a/wdriver.rs
+++ b/wdriver.rs
@@ -43,6 +43,7 @@ pub use std::process::{Command, Stdio};
 pub use std::thread::{self, sleep};
 pub use std::time;
 
+pub use otter::ensure_eq;
 pub use otter::commands::{MgmtCommand, MgmtResponse};
 pub use otter::commands::{MgmtGameInstruction, MgmtGameResponse};
 pub use otter::commands::{MgmtGameUpdateMode};
diff --git a/wdriver/wdt-simple.rs b/wdriver/wdt-simple.rs
index 44c8ee82..cba2c188 100644
--- a/wdriver/wdt-simple.rs
+++ b/wdriver/wdt-simple.rs
@@ -57,9 +57,9 @@ fn main(){
         .perform()
         .always_context("rotate")?;
 
-      let transform = format!("rotate(-90");
+      let transform = format!("rotate(-90)");
       let pd = w.find_element(By::Id("piece4.1"))?;
-      ensure!(pd.get_attribute("transform")? == Some(transform));
+      ensure_eq!(pd.get_attribute("transform")?, Some(transform));
       w.synch()?;
     }
 
-- 
2.30.2