From d2241ad65fbf0b6d3b6dfb699bab0ce15b76fd00 Mon Sep 17 00:00:00 2001
From: Konstantinos Tsanaktsidis <kj@kjtsanaktsidis.id.au>
Date: Wed, 16 Mar 2022 12:15:44 +1100
Subject: [PATCH] Fix number formatter following removal of Fixnum / Bignum
 from ruby-next (#50)

The current ruby head in CI removes Fixnum and Bignum classes, which has led to broken builds.

This fix attempts to coalesce the passed-in number to an `int64_t`; if that fails, it falls back to calling `unum_format_decimal` - if the versions of ICU does not support `unum_format_decimal`, a `RangeError` will be raised (which should not be an issue for modern versions of ICU)
---
 lib/ffi-icu/number_formatting.rb | 17 +++++++++++++----
 spec/number_formatting_spec.rb   |  5 +++++
 2 files changed, 18 insertions(+), 4 deletions(-)

diff --git a/lib/ffi-icu/number_formatting.rb b/lib/ffi-icu/number_formatting.rb
index 2225afd..5614dd0 100644
--- a/lib/ffi-icu/number_formatting.rb
+++ b/lib/ffi-icu/number_formatting.rb
@@ -68,8 +68,19 @@ module ICU
             case number
             when Float
               needed_length = Lib.unum_format_double(@f, number, out_ptr, needed_length, nil, error)
-            when Fixnum
-              needed_length = Lib.unum_format_int32(@f, number, out_ptr, needed_length, nil, error)
+            when Integer
+              begin
+                # Try doing it fast, for integers that can be marshaled into an int64_t
+                needed_length = Lib.unum_format_int64(@f, number, out_ptr, needed_length, nil, error)
+              rescue RangeError
+                # Fall back to stringifying in Ruby and passing that to ICU
+                unless defined? Lib.unum_format_decimal
+                  raise RangeError,"Number #{number} is too big to fit in int64_t and your "\
+                                    "ICU version is too old to have unum_format_decimal"
+                end
+                string_version = number.to_s
+                needed_length = Lib.unum_format_decimal(@f, string_version, string_version.bytesize, out_ptr, needed_length, nil, error)
+              end
             when BigDecimal
               string_version = number.to_s('F')
               if Lib.respond_to? :unum_format_decimal
@@ -77,8 +88,6 @@ module ICU
               else
                 needed_length = Lib.unum_format_double(@f, number.to_f, out_ptr, needed_length, nil, error)
               end
-            when Bignum
-              needed_length = Lib.unum_format_int64(@f, number, out_ptr, needed_length, nil, error)
             end
           end
           out_ptr.string needed_length
diff --git a/spec/number_formatting_spec.rb b/spec/number_formatting_spec.rb
index 27e759c..03bff01 100644
--- a/spec/number_formatting_spec.rb
+++ b/spec/number_formatting_spec.rb
@@ -69,6 +69,11 @@ module ICU
           expect { NumberFormatting.create('en-US', :currency, style: :iso) }.to raise_error(StandardError)
         end
       end
+
+      it 'should format a bignum' do
+        str = NumberFormatting.format_number("en", 1_000_000_000_000_000_000_000_000_000_000_000_000_000)
+        expect(str).to eq('1,000,000,000,000,000,000,000,000,000,000,000,000,000')
+      end
     end
   end # NumberFormatting
 end # ICU