From 03add2d31a1e940169c31d47705b5e2fd725c05d Mon Sep 17 00:00:00 2001
From: Tim Holy <tim.holy@gmail.com>
Date: Thu, 13 Jul 2017 14:50:45 -0500
Subject: [PATCH] Add atsign-compat support for `CartesianRange`

---
 README.md        |  5 +++++
 src/Compat.jl    |  8 ++++++++
 test/runtests.jl | 14 ++++++++++++++
 3 files changed, 27 insertions(+)

diff --git a/README.md b/README.md
index 8228fafef..a56448f4a 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}})`. 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`
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..0cc938df6 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(1:5, 2:4)) == 2
+    @test_throws MethodError cr(CartesianRange(1:5, 2:4, -1:1))
+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(1:5, 2:4)) == 2
+        @test_throws MethodError cr(CartesianRange(1:5, 2:4, -1:1))
+    end
+end
+
 include("to-be-deprecated.jl")
 
 nothing