From b42706c1d6ce4f1aeb8d380b7feb2a466ef6da15 Mon Sep 17 00:00:00 2001
From: Mark Thom <markjordanthom@gmail.com>
Date: Wed, 19 Dec 2018 09:27:08 -0700
Subject: [PATCH] make insert_from_end work correctly

---
 src/prolog/heap_print.rs | 3 ++-
 src/tests.rs             | 3 ++-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/prolog/heap_print.rs b/src/prolog/heap_print.rs
index 4c577974..8e1bcc5e 100644
--- a/src/prolog/heap_print.rs
+++ b/src/prolog/heap_print.rs
@@ -82,7 +82,8 @@ impl HCValueOutputter for PrinterOutputter {
     }
 
     fn insert_from_end(&mut self, idx: usize, c: char) {
-        self.contents.insert(idx, c);
+        let len = self.contents.len();
+        self.contents.insert(len - idx, c);
     }
 
     fn result(self) -> Self::Output {
diff --git a/src/tests.rs b/src/tests.rs
index 9602fba8..a7ae5558 100644
--- a/src/tests.rs
+++ b/src/tests.rs
@@ -51,7 +51,8 @@ impl HCValueOutputter for TestOutputter {
     }
 
     fn insert_from_end(&mut self, idx: usize, c: char) {
-        self.focus.insert(idx, c);
+        let len = self.focus.len();
+        self.focus.insert(len - idx, c);
     }
     
     fn result(self) -> Self::Output {
-- 
2.54.0