From 25e903bba6249cb3a8bb1c92c1a78ef17cdfed05 Mon Sep 17 00:00:00 2001
From: eulerkochy <kc99.kol@gmail.com>
Date: Wed, 10 Apr 2019 11:19:33 +0530
Subject: [PATCH 01/15] add findfirst, findlast for searching char in strings

---
 base/strings/search.jl | 35 ++++++++++++++++++++++++++--
 test/strings/search.jl | 52 ++++++++++++++++++++++--------------------
 2 files changed, 60 insertions(+), 27 deletions(-)

diff --git a/base/strings/search.jl b/base/strings/search.jl
index 8b62b34bc2d07..b8d3d6e707188 100644
--- a/base/strings/search.jl
+++ b/base/strings/search.jl
@@ -101,8 +101,23 @@ julia> findfirst("Julia", "JuliaLang")
 1:5
 ```
 """
-findfirst(pattern::AbstractString, string::AbstractString) =
-    findnext(pattern, string, firstindex(string))
+findfirst(pattern::AbstractString, string::AbstractString) = findnext(pattern, string, firstindex(string))
+
+"""
+    findfirst(ch::Char, string::AbstractString)
+
+Find the first occurrence of `ch` in `string`. Equivalent to
+[`findfirst(isequal(ch), string)`](@ref).
+
+# Examples
+```jldoctest
+julia> findfirst('a', "happy")
+2
+
+julia> findfirst('z', "happy") # returns nothing, but not printed in the REPL
+```
+"""
+findfirst(ch::Char, string::AbstractString) = findfirst(isequal(ch), string)
 
 # AbstractString implementation of the generic findnext interface
 function findnext(testf::Function, s::AbstractString, i::Integer)
@@ -273,6 +288,22 @@ julia> findfirst("Julia", "JuliaLang")
 findlast(pattern::AbstractString, string::AbstractString) =
     findprev(pattern, string, lastindex(string))
 
+"""
+    findlast(ch::Char, string::AbstractString)
+
+Find the last occurrence of `ch` in `string`. Equivalent to
+[`findlast(isequal(ch), string)`](@ref).
+
+# Examples
+```jldoctest
+julia> findlast('p', "happy")
+4
+
+julia> findlast('z', "happy") # returns nothing, but not printed in the REPL
+```
+"""
+findlast(ch::Char, string::AbstractString) = findlast(isequal(ch), string)
+
 # AbstractString implementation of the generic findprev interface
 function findprev(testf::Function, s::AbstractString, i::Integer)
     if i < 1
diff --git a/test/strings/search.jl b/test/strings/search.jl
index e9b6a678baa3a..7bdbca681fdf0 100644
--- a/test/strings/search.jl
+++ b/test/strings/search.jl
@@ -24,41 +24,43 @@ end
 
 # ascii forward search
 for str in [astr, GenericString(astr)]
-    @test_throws BoundsError findnext(isequal('z'), str, 0)
-    @test_throws BoundsError findnext(isequal('∀'), str, 0)
-    @test findfirst(isequal('x'), str) == nothing
-    @test findfirst(isequal('\0'), str) == nothing
-    @test findfirst(isequal('\u80'), str) == nothing
-    @test findfirst(isequal('∀'), str) == nothing
-    @test findfirst(isequal('H'), str) == 1
-    @test findfirst(isequal('l'), str) == 3
-    @test findnext(isequal('l'), str, 4) == 4
-    @test findnext(isequal('l'), str, 5) == 11
-    @test findnext(isequal('l'), str, 12) == nothing
-    @test findfirst(isequal(','), str) == 6
-    @test findnext(isequal(','), str, 7) == nothing
-    @test findfirst(isequal('\n'), str) == 14
-    @test findnext(isequal('\n'), str, 15) == nothing
-    @test_throws BoundsError findnext(isequal('ε'), str, nextind(str,lastindex(str))+1)
-    @test_throws BoundsError findnext(isequal('a'), str, nextind(str,lastindex(str))+1)
+        @test_throws BoundsError findnext(isequal('z'), str, 0)
+        @test_throws BoundsError findnext(isequal('∀'), str, 0)
+        @test findfirst('x', str) == nothing
+        @test findfirst('\0', str) == nothing
+        @test findfirst('\u80', str) == nothing
+        @test findfirst('∀', str) == nothing
+        @test findfirst('H', str) == 1
+        @test findfirst('l', str) == 3
+        @test findfirst('e', str) == 2
+        @test findfirst('u', str) == nothing
+        @test findnext(isequal('l'), str, 4) == 4
+        @test findnext(isequal('l'), str, 5) == 11
+        @test findnext(isequal('l'), str, 12) == nothing
+        @test findfirst(',', str) == 6
+        @test findnext(isequal(','), str, 7) == nothing
+        @test findfirst('\n', str) == 14
+        @test findnext(isequal('\n'), str, 15) == nothing
+        @test_throws BoundsError findnext(isequal('ε'), str, nextind(str,lastindex(str))+1)
+        @test_throws BoundsError findnext(isequal('a'), str, nextind(str,lastindex(str))+1)
 end
 
 # ascii backward search
 for str in [astr]
-    @test findlast(isequal('x'), str) == nothing
-    @test findlast(isequal('\0'), str) == nothing
-    @test findlast(isequal('\u80'), str) == nothing
-    @test findlast(isequal('∀'), str) == nothing
-    @test findlast(isequal('H'), str) == 1
+    @test findlast('x', str) == nothing
+    @test findlast('\0', str) == nothing
+    @test findlast('\u80', str) == nothing
+    @test findlast('∀', str) == nothing
+    @test findlast('H', str) == 1
     @test findprev(isequal('H'), str, 0) == nothing
-    @test findlast(isequal('l'), str) == 11
+    @test findlast('l', str) == 11
     @test findprev(isequal('l'), str, 5) == 4
     @test findprev(isequal('l'), str, 4) == 4
     @test findprev(isequal('l'), str, 3) == 3
     @test findprev(isequal('l'), str, 2) == nothing
-    @test findlast(isequal(','), str) == 6
+    @test findlast(',', str) == 6
     @test findprev(isequal(','), str, 5) == nothing
-    @test findlast(isequal('\n'), str) == 14
+    @test findlast('\n', str) == 14
 end
 
 # utf-8 forward search

From b70976333972f9b83d30ae4a917617f0b7f146e9 Mon Sep 17 00:00:00 2001
From: Koustav Chowdhury <kc99.kol@gmail.com>
Date: Wed, 10 Apr 2019 23:05:01 +0530
Subject: [PATCH 02/15] Fix indentation

---
 test/strings/search.jl | 38 +++++++++++++++++++-------------------
 1 file changed, 19 insertions(+), 19 deletions(-)

diff --git a/test/strings/search.jl b/test/strings/search.jl
index 7bdbca681fdf0..f0727e783ced7 100644
--- a/test/strings/search.jl
+++ b/test/strings/search.jl
@@ -24,25 +24,25 @@ end
 
 # ascii forward search
 for str in [astr, GenericString(astr)]
-        @test_throws BoundsError findnext(isequal('z'), str, 0)
-        @test_throws BoundsError findnext(isequal('∀'), str, 0)
-        @test findfirst('x', str) == nothing
-        @test findfirst('\0', str) == nothing
-        @test findfirst('\u80', str) == nothing
-        @test findfirst('∀', str) == nothing
-        @test findfirst('H', str) == 1
-        @test findfirst('l', str) == 3
-        @test findfirst('e', str) == 2
-        @test findfirst('u', str) == nothing
-        @test findnext(isequal('l'), str, 4) == 4
-        @test findnext(isequal('l'), str, 5) == 11
-        @test findnext(isequal('l'), str, 12) == nothing
-        @test findfirst(',', str) == 6
-        @test findnext(isequal(','), str, 7) == nothing
-        @test findfirst('\n', str) == 14
-        @test findnext(isequal('\n'), str, 15) == nothing
-        @test_throws BoundsError findnext(isequal('ε'), str, nextind(str,lastindex(str))+1)
-        @test_throws BoundsError findnext(isequal('a'), str, nextind(str,lastindex(str))+1)
+    @test_throws BoundsError findnext(isequal('z'), str, 0)
+    @test_throws BoundsError findnext(isequal('∀'), str, 0)
+    @test findfirst('x', str) == nothing
+    @test findfirst('\0', str) == nothing
+    @test findfirst('\u80', str) == nothing
+    @test findfirst('∀', str) == nothing
+    @test findfirst('H', str) == 1
+    @test findfirst('l', str) == 3
+    @test findfirst('e', str) == 2
+    @test findfirst('u', str) == nothing
+    @test findnext(isequal('l'), str, 4) == 4
+    @test findnext(isequal('l'), str, 5) == 11
+    @test findnext(isequal('l'), str, 12) == nothing
+    @test findfirst(',', str) == 6
+    @test findnext(isequal(','), str, 7) == nothing
+    @test findfirst('\n', str) == 14
+    @test findnext(isequal('\n'), str, 15) == nothing
+    @test_throws BoundsError findnext(isequal('ε'), str, nextind(str,lastindex(str))+1)
+    @test_throws BoundsError findnext(isequal('a'), str, nextind(str,lastindex(str))+1)
 end
 
 # ascii backward search

From 1f99cd8d0696999c74a2b59dcee1a9696681ab83 Mon Sep 17 00:00:00 2001
From: Koustav Chowdhury <kc99.kol@gmail.com>
Date: Wed, 10 Apr 2019 23:08:23 +0530
Subject: [PATCH 03/15] Update docstrings

---
 base/strings/search.jl | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/base/strings/search.jl b/base/strings/search.jl
index b8d3d6e707188..2bd8f178b8e3f 100644
--- a/base/strings/search.jl
+++ b/base/strings/search.jl
@@ -114,7 +114,8 @@ Find the first occurrence of `ch` in `string`. Equivalent to
 julia> findfirst('a', "happy")
 2
 
-julia> findfirst('z', "happy") # returns nothing, but not printed in the REPL
+julia> findfirst('z', "happy") === nothing
+true
 ```
 """
 findfirst(ch::Char, string::AbstractString) = findfirst(isequal(ch), string)
@@ -299,7 +300,8 @@ Find the last occurrence of `ch` in `string`. Equivalent to
 julia> findlast('p', "happy")
 4
 
-julia> findlast('z', "happy") # returns nothing, but not printed in the REPL
+julia> findlast('z', "happy") === nothing
+true
 ```
 """
 findlast(ch::Char, string::AbstractString) = findlast(isequal(ch), string)

From c0660a5fc00905c1e15bdf25b37b91c96079ff56 Mon Sep 17 00:00:00 2001
From: eulerkochy <kc99.kol@gmail.com>
Date: Mon, 15 Apr 2019 02:56:53 +0530
Subject: [PATCH 04/15] Add compat for Julia-1.3

---
 base/strings/search.jl | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/base/strings/search.jl b/base/strings/search.jl
index 2bd8f178b8e3f..346698ae86c20 100644
--- a/base/strings/search.jl
+++ b/base/strings/search.jl
@@ -109,6 +109,9 @@ findfirst(pattern::AbstractString, string::AbstractString) = findnext(pattern, s
 Find the first occurrence of `ch` in `string`. Equivalent to
 [`findfirst(isequal(ch), string)`](@ref).
 
+!!! compat "Julia 1.3"
+    This function requires at least Julia 1.3.
+
 # Examples
 ```jldoctest
 julia> findfirst('a', "happy")
@@ -295,6 +298,9 @@ findlast(pattern::AbstractString, string::AbstractString) =
 Find the last occurrence of `ch` in `string`. Equivalent to
 [`findlast(isequal(ch), string)`](@ref).
 
+!!! compat "Julia 1.3"
+    This function requires at least Julia 1.3.
+
 # Examples
 ```jldoctest
 julia> findlast('p', "happy")

From 3e9bdbff846c0b57dd75a283e229dee5dffa062e Mon Sep 17 00:00:00 2001
From: eulerkochy <kc99.kol@gmail.com>
Date: Mon, 15 Apr 2019 03:02:47 +0530
Subject: [PATCH 05/15] Add news

---
 NEWS.md | 1 +
 1 file changed, 1 insertion(+)

diff --git a/NEWS.md b/NEWS.md
index 2afaf9e2adfd2..583f4605199f6 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -50,6 +50,7 @@ New library functions
 * Added `Base.hasproperty` and `Base.hasfield` ([#28850]).
 * One argument `!=(x)`, `>(x)`, `>=(x)`, `<(x)`, `<=(x)` has been added for currying,
   similar to the existing `==(x)` and `isequal(x)` methods ([#30915]).
+* `findfirst` and `findlast` now addresses search for a character in a string ([#31664]).
 
 Standard library changes
 ------------------------

From d82a03d63be0fa7957e2302de73731b82a14ae30 Mon Sep 17 00:00:00 2001
From: Koustav Chowdhury <kc99.kol@gmail.com>
Date: Mon, 15 Apr 2019 03:17:07 +0530
Subject: [PATCH 06/15] Update search.jl

---
 base/strings/search.jl | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/base/strings/search.jl b/base/strings/search.jl
index 346698ae86c20..04beec0847aa2 100644
--- a/base/strings/search.jl
+++ b/base/strings/search.jl
@@ -101,7 +101,8 @@ julia> findfirst("Julia", "JuliaLang")
 1:5
 ```
 """
-findfirst(pattern::AbstractString, string::AbstractString) = findnext(pattern, string, firstindex(string))
+findfirst(pattern::AbstractString, string::AbstractString) = 
+    findnext(pattern, string, firstindex(string))
 
 """
     findfirst(ch::Char, string::AbstractString)

From 8d2fba38a56ab2db431ef86bc44dfd4ae9f8aa4f Mon Sep 17 00:00:00 2001
From: eulerkochy <kc99.kol@gmail.com>
Date: Mon, 15 Apr 2019 04:00:15 +0530
Subject: [PATCH 07/15] add findnext, findprev for char ; update tests

---
 base/strings/search.jl | 42 ++++++++++++++++++++++++++++++++++++++++--
 test/strings/search.jl | 30 +++++++++++++++---------------
 2 files changed, 55 insertions(+), 17 deletions(-)

diff --git a/base/strings/search.jl b/base/strings/search.jl
index 04beec0847aa2..9b8a4c38ca13a 100644
--- a/base/strings/search.jl
+++ b/base/strings/search.jl
@@ -122,7 +122,7 @@ julia> findfirst('z', "happy") === nothing
 true
 ```
 """
-findfirst(ch::Char, string::AbstractString) = findfirst(isequal(ch), string)
+findfirst(ch::Char, string::AbstractString) = findfirst(==(ch), string)
 
 # AbstractString implementation of the generic findnext interface
 function findnext(testf::Function, s::AbstractString, i::Integer)
@@ -275,6 +275,25 @@ julia> findnext("Lang", "JuliaLang", 2)
 """
 findnext(t::AbstractString, s::AbstractString, i::Integer) = _search(s, t, i)
 
+"""
+    findnext(ch::Char, string::AbstractString, start::Integer)
+
+Find the next occurrence of `ch` in `string` starting at position `start`.
+
+!!! compat "Julia 1.3"
+    This function requires at least Julia 1.3.
+
+# Examples
+```jldoctest
+julia> findnext(`z`, "Hello to the world", 1) === nothing
+true
+
+julia> findnext(`o`, "Hello to the world", 6)
+8
+```
+"""
+findnext(ch::Char, string::AbstractString, ind::Integer) = findnext(==(ch), string, ind)
+
 """
     findlast(pattern::AbstractString, string::AbstractString)
 
@@ -311,7 +330,7 @@ julia> findlast('z', "happy") === nothing
 true
 ```
 """
-findlast(ch::Char, string::AbstractString) = findlast(isequal(ch), string)
+findlast(ch::Char, string::AbstractString) = findlast(==(ch), string)
 
 # AbstractString implementation of the generic findprev interface
 function findprev(testf::Function, s::AbstractString, i::Integer)
@@ -468,6 +487,25 @@ julia> findprev("Julia", "JuliaLang", 6)
 """
 findprev(t::AbstractString, s::AbstractString, i::Integer) = _rsearch(s, t, i)
 
+"""
+    findprev(ch::Char, string::AbstractString, start::Integer)
+
+Find the previous occurrence of `ch` in `string` starting at position `start`.
+
+!!! compat "Julia 1.3"
+    This function requires at least Julia 1.3.
+
+# Examples
+```jldoctest
+julia> findprev('z', "Hello to the world", 18) === nothing
+true
+
+julia> findprev('o', "Hello to the world", 18)
+15
+```
+"""
+findprev(ch::Char, string::AbstractString, ind::Integer) = findprev(==(ch), string, ind)
+
 """
     occursin(needle::Union{AbstractString,Regex,AbstractChar}, haystack::AbstractString)
 
diff --git a/test/strings/search.jl b/test/strings/search.jl
index f0727e783ced7..629e7c9f1f708 100644
--- a/test/strings/search.jl
+++ b/test/strings/search.jl
@@ -24,8 +24,8 @@ end
 
 # ascii forward search
 for str in [astr, GenericString(astr)]
-    @test_throws BoundsError findnext(isequal('z'), str, 0)
-    @test_throws BoundsError findnext(isequal('∀'), str, 0)
+    @test_throws BoundsError findnext('z', str, 0)
+    @test_throws BoundsError findnext('∀', str, 0)
     @test findfirst('x', str) == nothing
     @test findfirst('\0', str) == nothing
     @test findfirst('\u80', str) == nothing
@@ -34,15 +34,15 @@ for str in [astr, GenericString(astr)]
     @test findfirst('l', str) == 3
     @test findfirst('e', str) == 2
     @test findfirst('u', str) == nothing
-    @test findnext(isequal('l'), str, 4) == 4
-    @test findnext(isequal('l'), str, 5) == 11
-    @test findnext(isequal('l'), str, 12) == nothing
+    @test findnext('l', str, 4) == 4
+    @test findnext('l', str, 5) == 11
+    @test findnext('l', str, 12) == nothing
     @test findfirst(',', str) == 6
-    @test findnext(isequal(','), str, 7) == nothing
+    @test findnext(',', str, 7) == nothing
     @test findfirst('\n', str) == 14
-    @test findnext(isequal('\n'), str, 15) == nothing
-    @test_throws BoundsError findnext(isequal('ε'), str, nextind(str,lastindex(str))+1)
-    @test_throws BoundsError findnext(isequal('a'), str, nextind(str,lastindex(str))+1)
+    @test findnext('\n', str, 15) == nothing
+    @test_throws BoundsError findnext('ε', str, nextind(str,lastindex(str))+1)
+    @test_throws BoundsError findnext('a', str, nextind(str,lastindex(str))+1)
 end
 
 # ascii backward search
@@ -52,14 +52,14 @@ for str in [astr]
     @test findlast('\u80', str) == nothing
     @test findlast('∀', str) == nothing
     @test findlast('H', str) == 1
-    @test findprev(isequal('H'), str, 0) == nothing
+    @test findprev('H', str, 0) == nothing
     @test findlast('l', str) == 11
-    @test findprev(isequal('l'), str, 5) == 4
-    @test findprev(isequal('l'), str, 4) == 4
-    @test findprev(isequal('l'), str, 3) == 3
-    @test findprev(isequal('l'), str, 2) == nothing
+    @test findprev('l', str, 5) == 4
+    @test findprev('l', str, 4) == 4
+    @test findprev('l', str, 3) == 3
+    @test findprev('l', str, 2) == nothing
     @test findlast(',', str) == 6
-    @test findprev(isequal(','), str, 5) == nothing
+    @test findprev(',', str, 5) == nothing
     @test findlast('\n', str) == 14
 end
 

From 5d6150e9235a07c1576a780caeb9c5689c3a73d9 Mon Sep 17 00:00:00 2001
From: eulerkochy <kc99.kol@gmail.com>
Date: Mon, 15 Apr 2019 04:03:42 +0530
Subject: [PATCH 08/15] update news

---
 NEWS.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/NEWS.md b/NEWS.md
index b77adc719e4bd..bf58c934fd493 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -20,7 +20,7 @@ Build system changes
 New library functions
 ---------------------
 
-* `findfirst` and `findlast` now addresses search for a character in a string ([#31664]).
+* `findfirst`, `findlast`, `findnext` and `findprev` now addresses search for a character in a string ([#31664]).
 
 Standard library changes
 ------------------------

From c6f14f34e1ba6ce85ee93bc21761163f6b6ccf1b Mon Sep 17 00:00:00 2001
From: Milan Bouchet-Valat <nalimilan@club.fr>
Date: Tue, 16 Apr 2019 01:01:31 +0530
Subject: [PATCH 09/15] Update NEWS.md

Co-Authored-By: eulerkochy <kc99.kol@gmail.com>
---
 NEWS.md | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/NEWS.md b/NEWS.md
index bf58c934fd493..8c9b2e7c84d85 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -20,7 +20,8 @@ Build system changes
 New library functions
 ---------------------
 
-* `findfirst`, `findlast`, `findnext` and `findprev` now addresses search for a character in a string ([#31664]).
+* `findfirst`, `findlast`, `findnext` and `findprev` now accept a character as first argument
+  to search for that character in a string passed as the second argument ([#31664]).
 
 Standard library changes
 ------------------------

From 6702542cd767524dcf4f61f5ac67240dbb1f7a48 Mon Sep 17 00:00:00 2001
From: Milan Bouchet-Valat <nalimilan@club.fr>
Date: Tue, 16 Apr 2019 01:01:50 +0530
Subject: [PATCH 10/15] Update base/strings/search.jl

Co-Authored-By: eulerkochy <kc99.kol@gmail.com>
---
 base/strings/search.jl | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/base/strings/search.jl b/base/strings/search.jl
index 9b8a4c38ca13a..090f25be6e376 100644
--- a/base/strings/search.jl
+++ b/base/strings/search.jl
@@ -101,7 +101,7 @@ julia> findfirst("Julia", "JuliaLang")
 1:5
 ```
 """
-findfirst(pattern::AbstractString, string::AbstractString) = 
+findfirst(pattern::AbstractString, string::AbstractString) =
     findnext(pattern, string, firstindex(string))
 
 """

From 3ee9a616fa4e7e09b9898f9434edd0b5e0414b6c Mon Sep 17 00:00:00 2001
From: Koustav Chowdhury <kc99.kol@gmail.com>
Date: Tue, 16 Apr 2019 01:03:21 +0530
Subject: [PATCH 11/15] Update search.jl

---
 base/strings/search.jl | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/base/strings/search.jl b/base/strings/search.jl
index 090f25be6e376..5c85639d2e577 100644
--- a/base/strings/search.jl
+++ b/base/strings/search.jl
@@ -107,8 +107,7 @@ findfirst(pattern::AbstractString, string::AbstractString) =
 """
     findfirst(ch::Char, string::AbstractString)
 
-Find the first occurrence of `ch` in `string`. Equivalent to
-[`findfirst(isequal(ch), string)`](@ref).
+Find the first occurrence of `ch` in `string`.
 
 !!! compat "Julia 1.3"
     This function requires at least Julia 1.3.
@@ -315,8 +314,7 @@ findlast(pattern::AbstractString, string::AbstractString) =
 """
     findlast(ch::Char, string::AbstractString)
 
-Find the last occurrence of `ch` in `string`. Equivalent to
-[`findlast(isequal(ch), string)`](@ref).
+Find the last occurrence of `ch` in `string`.
 
 !!! compat "Julia 1.3"
     This function requires at least Julia 1.3.

From c48e47248422cc7c8c971e807aaa085be2ecb388 Mon Sep 17 00:00:00 2001
From: Koustav Chowdhury <kc99.kol@gmail.com>
Date: Tue, 16 Apr 2019 05:01:40 +0530
Subject: [PATCH 12/15] Update search.jl

---
 test/strings/search.jl | 37 +++++++++++++++++++++++++++++++++++++
 1 file changed, 37 insertions(+)

diff --git a/test/strings/search.jl b/test/strings/search.jl
index 629e7c9f1f708..5b9860630b078 100644
--- a/test/strings/search.jl
+++ b/test/strings/search.jl
@@ -23,6 +23,26 @@ end
 @test_throws BoundsError findnext(isequal(0x1),b"\x1\x2",0)
 
 # ascii forward search
+for str in [astr, GenericString(astr)]
+    @test_throws BoundsError findnext(isequal('z'), str, 0)
+    @test_throws BoundsError findnext(isequal('∀'), str, 0)
+    @test findfirst(isequal('x'), str) == nothing
+    @test findfirst(isequal('\0'), str) == nothing
+    @test findfirst(isequal('\u80'), str) == nothing
+    @test findfirst(isequal('∀'), str) == nothing
+    @test findfirst(isequal('H'), str) == 1
+    @test findfirst(isequal('l'), str) == 3
+    @test findnext(isequal('l'), str, 4) == 4
+    @test findnext(isequal('l'), str, 5) == 11
+    @test findnext(isequal('l'), str, 12) == nothing
+    @test findfirst(isequal(','), str) == 6
+    @test findnext(isequal(','), str, 7) == nothing
+    @test findfirst(isequal('\n'), str) == 14
+    @test findnext(isequal('\n'), str, 15) == nothing
+    @test_throws BoundsError findnext(isequal('ε'), str, nextind(str,lastindex(str))+1)
+    @test_throws BoundsError findnext(isequal('a'), str, nextind(str,lastindex(str))+1)
+end
+
 for str in [astr, GenericString(astr)]
     @test_throws BoundsError findnext('z', str, 0)
     @test_throws BoundsError findnext('∀', str, 0)
@@ -46,6 +66,23 @@ for str in [astr, GenericString(astr)]
 end
 
 # ascii backward search
+for str in [astr]
+    @test findlast(isequal('x'), str) == nothing
+    @test findlast(isequal('\0'), str) == nothing
+    @test findlast(isequal('\u80'), str) == nothing
+    @test findlast(isequal('∀'), str) == nothing
+    @test findlast(isequal('H'), str) == 1
+    @test findprev(isequal('H'), str, 0) == nothing
+    @test findlast(isequal('l'), str) == 11
+    @test findprev(isequal('l'), str, 5) == 4
+    @test findprev(isequal('l'), str, 4) == 4
+    @test findprev(isequal('l'), str, 3) == 3
+    @test findprev(isequal('l'), str, 2) == nothing
+    @test findlast(isequal(','), str) == 6
+    @test findprev(isequal(','), str, 5) == nothing
+    @test findlast(isequal('\n'), str) == 14
+end
+
 for str in [astr]
     @test findlast('x', str) == nothing
     @test findlast('\0', str) == nothing

From 623638978805f08d1176304ea6c2a30e1b76129e Mon Sep 17 00:00:00 2001
From: Milan Bouchet-Valat <nalimilan@club.fr>
Date: Tue, 16 Apr 2019 14:01:59 +0200
Subject: [PATCH 13/15] Use AbstractChar

---
 base/strings/search.jl | 26 ++++++++++++++------------
 1 file changed, 14 insertions(+), 12 deletions(-)

diff --git a/base/strings/search.jl b/base/strings/search.jl
index 5c85639d2e577..66291a89002b7 100644
--- a/base/strings/search.jl
+++ b/base/strings/search.jl
@@ -105,9 +105,9 @@ findfirst(pattern::AbstractString, string::AbstractString) =
     findnext(pattern, string, firstindex(string))
 
 """
-    findfirst(ch::Char, string::AbstractString)
+    findfirst(ch::AbstractChar, string::AbstractString)
 
-Find the first occurrence of `ch` in `string`.
+Find the first occurrence of character `ch` in `string`.
 
 !!! compat "Julia 1.3"
     This function requires at least Julia 1.3.
@@ -121,7 +121,7 @@ julia> findfirst('z', "happy") === nothing
 true
 ```
 """
-findfirst(ch::Char, string::AbstractString) = findfirst(==(ch), string)
+findfirst(ch::AbstractChar, string::AbstractString) = findfirst(==(ch), string)
 
 # AbstractString implementation of the generic findnext interface
 function findnext(testf::Function, s::AbstractString, i::Integer)
@@ -275,9 +275,9 @@ julia> findnext("Lang", "JuliaLang", 2)
 findnext(t::AbstractString, s::AbstractString, i::Integer) = _search(s, t, i)
 
 """
-    findnext(ch::Char, string::AbstractString, start::Integer)
+    findnext(ch::AbstractChar, string::AbstractString, start::Integer)
 
-Find the next occurrence of `ch` in `string` starting at position `start`.
+Find the next occurrence of character `ch` in `string` starting at position `start`.
 
 !!! compat "Julia 1.3"
     This function requires at least Julia 1.3.
@@ -291,7 +291,8 @@ julia> findnext(`o`, "Hello to the world", 6)
 8
 ```
 """
-findnext(ch::Char, string::AbstractString, ind::Integer) = findnext(==(ch), string, ind)
+findnext(ch::AbstractChar, string::AbstractString, ind::Integer) =
+    findnext(==(ch), string, ind)
 
 """
     findlast(pattern::AbstractString, string::AbstractString)
@@ -312,9 +313,9 @@ findlast(pattern::AbstractString, string::AbstractString) =
     findprev(pattern, string, lastindex(string))
 
 """
-    findlast(ch::Char, string::AbstractString)
+    findlast(ch::AbstractChar, string::AbstractString)
 
-Find the last occurrence of `ch` in `string`.
+Find the last occurrence of character `ch` in `string`.
 
 !!! compat "Julia 1.3"
     This function requires at least Julia 1.3.
@@ -328,7 +329,7 @@ julia> findlast('z', "happy") === nothing
 true
 ```
 """
-findlast(ch::Char, string::AbstractString) = findlast(==(ch), string)
+findlast(ch::AbstractChar, string::AbstractString) = findlast(==(ch), string)
 
 # AbstractString implementation of the generic findprev interface
 function findprev(testf::Function, s::AbstractString, i::Integer)
@@ -486,9 +487,9 @@ julia> findprev("Julia", "JuliaLang", 6)
 findprev(t::AbstractString, s::AbstractString, i::Integer) = _rsearch(s, t, i)
 
 """
-    findprev(ch::Char, string::AbstractString, start::Integer)
+    findprev(ch::AbstractChar, string::AbstractString, start::Integer)
 
-Find the previous occurrence of `ch` in `string` starting at position `start`.
+Find the previous occurrence of character `ch` in `string` starting at position `start`.
 
 !!! compat "Julia 1.3"
     This function requires at least Julia 1.3.
@@ -502,7 +503,8 @@ julia> findprev('o', "Hello to the world", 18)
 15
 ```
 """
-findprev(ch::Char, string::AbstractString, ind::Integer) = findprev(==(ch), string, ind)
+findprev(ch::AbstractChar, string::AbstractString, ind::Integer) =
+    findprev(==(ch), string, ind)
 
 """
     occursin(needle::Union{AbstractString,Regex,AbstractChar}, haystack::AbstractString)

From 19c352fb910b17c7121fec8a8421661d35d37bcf Mon Sep 17 00:00:00 2001
From: Koustav Chowdhury <kc99.kol@gmail.com>
Date: Wed, 29 May 2019 18:54:30 +0530
Subject: [PATCH 14/15] Update base/strings/search.jl

Co-Authored-By: Stefan Karpinski <stefan@karpinski.org>
---
 base/strings/search.jl | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/base/strings/search.jl b/base/strings/search.jl
index 66291a89002b7..054efdbdee655 100644
--- a/base/strings/search.jl
+++ b/base/strings/search.jl
@@ -492,7 +492,7 @@ findprev(t::AbstractString, s::AbstractString, i::Integer) = _rsearch(s, t, i)
 Find the previous occurrence of character `ch` in `string` starting at position `start`.
 
 !!! compat "Julia 1.3"
-    This function requires at least Julia 1.3.
+    This method requires at least Julia 1.3.
 
 # Examples
 ```jldoctest

From 9a635dc09ac2e1017be9f73e273c25ef5f920703 Mon Sep 17 00:00:00 2001
From: Koustav Chowdhury <kc99.kol@gmail.com>
Date: Wed, 29 May 2019 18:55:12 +0530
Subject: [PATCH 15/15] Apply suggestions from code review

Co-Authored-By: Stefan Karpinski <stefan@karpinski.org>
---
 base/strings/search.jl | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/base/strings/search.jl b/base/strings/search.jl
index 054efdbdee655..6e3ff7e2133a0 100644
--- a/base/strings/search.jl
+++ b/base/strings/search.jl
@@ -110,7 +110,7 @@ findfirst(pattern::AbstractString, string::AbstractString) =
 Find the first occurrence of character `ch` in `string`.
 
 !!! compat "Julia 1.3"
-    This function requires at least Julia 1.3.
+    This method requires at least Julia 1.3.
 
 # Examples
 ```jldoctest
@@ -280,7 +280,7 @@ findnext(t::AbstractString, s::AbstractString, i::Integer) = _search(s, t, i)
 Find the next occurrence of character `ch` in `string` starting at position `start`.
 
 !!! compat "Julia 1.3"
-    This function requires at least Julia 1.3.
+    This method requires at least Julia 1.3.
 
 # Examples
 ```jldoctest
@@ -318,7 +318,7 @@ findlast(pattern::AbstractString, string::AbstractString) =
 Find the last occurrence of character `ch` in `string`.
 
 !!! compat "Julia 1.3"
-    This function requires at least Julia 1.3.
+    This method requires at least Julia 1.3.
 
 # Examples
 ```jldoctest