From 6130d2b14337dc0563a5f149af6f4334b9eb29fe Mon Sep 17 00:00:00 2001
From: Bruno Tavares <connect+github@bltavares.com>
Date: Wed, 26 Feb 2020 14:40:27 -0300
Subject: [PATCH] Move from failure to use stderr

Related to https://github.com/datrs/hypercore/issues/101
---
 Cargo.toml |  2 +-
 src/lib.rs | 24 +++++++++++++-----------
 2 files changed, 14 insertions(+), 12 deletions(-)

diff --git a/Cargo.toml b/Cargo.toml
index 7d19249..0f5a21e 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -10,7 +10,7 @@ readme = "README.md"
 edition = "2018"
 
 [dependencies]
-failure = "0.1.6"
+anyhow = "1.0.26"
 random-access-storage = "3.0.0"
 
 [dev-dependencies]
diff --git a/src/lib.rs b/src/lib.rs
index ebb05d0..da94d06 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -3,7 +3,7 @@
 #![cfg_attr(feature = "nightly", doc(include = "../README.md"))]
 #![cfg_attr(test, deny(warnings))]
 
-use failure::{ensure, Error};
+use anyhow::anyhow;
 use random_access_storage::RandomAccess;
 use std::cmp;
 use std::io;
@@ -53,7 +53,7 @@ impl RandomAccessMemory {
 }
 
 impl RandomAccess for RandomAccessMemory {
-  type Error = Error;
+  type Error = Box<dyn std::error::Error + Send + Sync>;
 
   fn write(&mut self, offset: u64, data: &[u8]) -> Result<(), Self::Error> {
     let new_len = offset + data.len() as u64;
@@ -106,15 +106,17 @@ impl RandomAccess for RandomAccessMemory {
   }
 
   fn read(&mut self, offset: u64, length: u64) -> Result<Vec<u8>, Self::Error> {
-    ensure!(
-      (offset + length) <= self.length,
-      format!(
-        "Read bounds exceeded. {} < {}..{}",
-        self.length,
-        offset,
-        offset + length
-      )
-    );
+    if (offset + length) > self.length {
+      return Err(
+        anyhow!(
+          "Read bounds exceeded. {} < {}..{}",
+          self.length,
+          offset,
+          offset + length
+        )
+        .into(),
+      );
+    };
 
     let mut page_num = (offset / self.page_size as u64) as usize;
     let mut page_cursor =