From ebb0996cfc7fbb6d5f962671b2d92a3773e2ec25 Mon Sep 17 00:00:00 2001
From: Sebastian Stock <42280794+sostock@users.noreply.github.com>
Date: Fri, 7 Aug 2020 11:17:31 +0200
Subject: [PATCH] Fix replace (#36953)

---
 base/strings/util.jl | 2 +-
 test/strings/util.jl | 3 +++
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/base/strings/util.jl b/base/strings/util.jl
index 934c8e902de86..e1e566568d11a 100644
--- a/base/strings/util.jl
+++ b/base/strings/util.jl
@@ -521,7 +521,7 @@ function replace(str::String, pat_repl::Pair; count::Integer=typemax(Int))
             i = k = nextind(str, k)
         end
         r = something(findnext(pattern,str,k), 0)
-        r == 0:-1 || n == count && break
+        r === 0:-1 || n == count && break
         j, k = first(r), last(r)
         n += 1
     end
diff --git a/test/strings/util.jl b/test/strings/util.jl
index 59024e972021b..7a144e3c35000 100644
--- a/test/strings/util.jl
+++ b/test/strings/util.jl
@@ -297,6 +297,9 @@ end
     @test replace("a", in("a") => typeof) == "Char"
     @test replace("a", ['a'] => typeof) == "Char"
 
+    # Issue 36953
+    @test replace("abc", "" => "_", count=1) == "_abc"
+
 end
 
 @testset "chomp/chop" begin