From 32ed45978ee16cb12e4c0cd0f0851e368161918f Mon Sep 17 00:00:00 2001
From: Ben Baumgold <4933671+baumgold@users.noreply.github.com>
Date: Sat, 13 May 2023 09:52:41 -0400
Subject: [PATCH 1/2] Limit TimeType subtraction to AbstractDateTime

---
 stdlib/Dates/src/arithmetic.jl  | 2 +-
 stdlib/Dates/test/arithmetic.jl | 6 ------
 2 files changed, 1 insertion(+), 7 deletions(-)

diff --git a/stdlib/Dates/src/arithmetic.jl b/stdlib/Dates/src/arithmetic.jl
index a847f749d0154..813cccf314c57 100644
--- a/stdlib/Dates/src/arithmetic.jl
+++ b/stdlib/Dates/src/arithmetic.jl
@@ -7,7 +7,7 @@
 # TimeType arithmetic
 (+)(x::TimeType) = x
 (-)(x::T, y::T) where {T<:TimeType} = x.instant - y.instant
-(-)(x::TimeType, y::TimeType) = -(promote(x, y)...)
+(-)(x::AbstractDateTime, y::AbstractDateTime) = -(promote(x, y)...)
 
 # Date-Time arithmetic
 """
diff --git a/stdlib/Dates/test/arithmetic.jl b/stdlib/Dates/test/arithmetic.jl
index 2e684815a3c86..aa7574080186a 100644
--- a/stdlib/Dates/test/arithmetic.jl
+++ b/stdlib/Dates/test/arithmetic.jl
@@ -11,12 +11,6 @@ using Dates
     @test Dates.CompoundPeriod(a - b) == Dates.Hour(12)
 end
 
-@testset "TimeType arithmetic" begin
-    a = Date(2023, 5, 1)
-    b = DateTime(2023, 5, 2)
-    @test b - a == Day(1)
-end
-
 @testset "Wrapping arithmetic for Months" begin
     # This ends up being trickier than expected because
     # the user might do 2014-01-01 + Month(-14)

From ff6dbb3ac9151851304801373db33403adf8602d Mon Sep 17 00:00:00 2001
From: Ben Baumgold <4933671+baumgold@users.noreply.github.com>
Date: Sat, 24 Jun 2023 10:08:28 -0400
Subject: [PATCH 2/2] fix stack overflow

---
 stdlib/Dates/src/arithmetic.jl | 1 +
 1 file changed, 1 insertion(+)

diff --git a/stdlib/Dates/src/arithmetic.jl b/stdlib/Dates/src/arithmetic.jl
index 813cccf314c57..83a2873b43409 100644
--- a/stdlib/Dates/src/arithmetic.jl
+++ b/stdlib/Dates/src/arithmetic.jl
@@ -7,6 +7,7 @@
 # TimeType arithmetic
 (+)(x::TimeType) = x
 (-)(x::T, y::T) where {T<:TimeType} = x.instant - y.instant
+(-)(x::T, y::T) where {T<:AbstractDateTime} = x.instant - y.instant
 (-)(x::AbstractDateTime, y::AbstractDateTime) = -(promote(x, y)...)
 
 # Date-Time arithmetic