From 4d722081cdcac55ea2c61a7c783aea92a3c72ffb Mon Sep 17 00:00:00 2001
From: Tim Holy <tim.holy@gmail.com>
Date: Thu, 13 Jul 2017 16:05:15 -0500
Subject: [PATCH] Add atsign-compat support for `CartesianRange`

---
 README.md        |  6 ++++++
 src/Compat.jl    |  8 ++++++++
 test/runtests.jl | 14 ++++++++++++++
 3 files changed, 28 insertions(+)

diff --git a/README.md b/README.md
index 8228fafef..9e372f760 100644
--- a/README.md
+++ b/README.md
@@ -83,6 +83,11 @@ Currently, the `@compat` macro supports the following syntaxes:
 
 * `Compat.collect(A)` returns an `Array`, no matter what indices the array `A` has (Julia 0.5 and higher). [#21257]
 
+* `@compat foo(::CartesianRange{N})` to replace the former
+  `foo(::CartesianRange{CartesianIndex{N}})` ([#20974]). Note that
+  `CartesianRange` now has two type parameters, so using them as
+  fields in other `struct`s requires manual intervention.
+
 ## Module Aliases
 
 * In 0.6, some 0.5 iterator functions have been moved to the `Base.Iterators`
@@ -377,6 +382,7 @@ includes this fix. Find the minimum version from there.
 [#20414]: https://github.com/JuliaLang/julia/issues/20414
 [#20418]: https://github.com/JuliaLang/julia/issues/20418
 [#20500]: https://github.com/JuliaLang/julia/issues/20500
+[#20974]: https://github.com/JuliaLang/julia/issues/20974
 [#21257]: https://github.com/JuliaLang/julia/issues/21257
 [#21346]: https://github.com/JuliaLang/julia/issues/21346
 [#22064]: https://github.com/JuliaLang/julia/issues/22064
diff --git a/src/Compat.jl b/src/Compat.jl
index baec4dc06..c6eb0522d 100644
--- a/src/Compat.jl
+++ b/src/Compat.jl
@@ -483,6 +483,14 @@ function _compat(ex::Expr)
             end
         end
     end
+    if VERSION < v"0.7.0-DEV.880"
+        if ex.head == :curly && ex.args[1] == :CartesianRange && length(ex.args) >= 2
+            a = ex.args[2]
+            if a != :CartesianIndex && !(isa(a, Expr) && a.head == :curly && a.args[1] == :CartesianIndex)
+                return Expr(:curly, :CartesianRange, Expr(:curly, :CartesianIndex, ex.args[2]))
+            end
+        end
+    end
     return Expr(ex.head, map(_compat, ex.args)...)
 end
 function _compat(ex::Symbol)
diff --git a/test/runtests.jl b/test/runtests.jl
index 116780b9a..dd0ddc2df 100644
--- a/test/runtests.jl
+++ b/test/runtests.jl
@@ -1893,6 +1893,20 @@ let
     @test_throws MethodError Dates.Month(1) < Dates.Day(1)
 end
 
+let
+    @compat cr(::CartesianRange{2}) = 2
+    @test cr(CartesianRange((5, 3))) == 2
+    @test_throws MethodError cr(CartesianRange((5, 3, 2)))
+end
+if VERSION < v"0.7.0-DEV.880"
+    # ensure we don't bork any non-updated expressions
+    let
+        @compat cr(::CartesianRange{CartesianIndex{2}}) = 2
+        @test cr(CartesianRange((5, 3))) == 2
+        @test_throws MethodError cr(CartesianRange((5, 3, 2)))
+    end
+end
+
 include("to-be-deprecated.jl")
 
 nothing