From 07d7c3b2e0f8c6b269ba167117cd3e549df2f342 Mon Sep 17 00:00:00 2001
From: Vinnie Falco <[email protected]>
Date: Wed, 13 Apr 2022 05:49:05 -0700
Subject: [PATCH] array::erase relocates correctly

fix #692
---
 boost/json/impl/array.ipp |  5 ++++-
 libs/json/test/array.cpp                    | 16 ++++++++++++++++
 2 files changed, 20 insertions(+), 1 deletion(-)

diff --git a/boost/json/impl/array.ipp b/boost/json/impl/array.ipp
index 4d067fb5..a2c7fd6d 100644
--- a/boost/json/impl/array.ipp
+++ b/boost/json/impl/array.ipp
@@ -491,8 +491,11 @@ erase(
     auto const p = &(*t_)[0] +
         (pos - &(*t_)[0]);
     destroy(p, p + 1);
-    relocate(p, p + 1, 1);
     --t_->size;
+    if(t_->size > 0)
+        relocate(p, p + 1,
+            t_->size - (p -
+                &(*t_)[0]));
     return p;
 }
 
diff --git a/libs/json/test/array.cpp b/libs/json/test/array.cpp
index 1cc87566..4516cc78 100644
--- a/libs/json/test/array.cpp
+++ b/libs/json/test/array.cpp
@@ -1269,6 +1269,21 @@ class array_test
             array{nullptr, "a", "b"}));
     }
 
+    void
+    testIssue692()
+    {
+	    array a;
+	    object obj;
+	    obj["test1"] = "hello";
+	    a.push_back(obj);
+	    a.push_back(obj);
+	    a.push_back(obj);
+	    a.push_back(obj);
+	    a.push_back(obj);
+	    while(a.size())
+		    a.erase(a.begin());
+    }
+
     void
     run()
     {
@@ -1283,6 +1298,7 @@ class array_test
         testExceptions();
         testEquality();
         testHash();
+        testIssue692();
     }
 };