Fix `Numeric#step` to infinity; ref. #4555

mrblib/numeric.rb

@@ -105,14 +105,14 @@ module Integral
     return to_enum(:step, num, step) unless block
 
     i = __coerce_step_counter(num, step)
-    if num == nil
+    if num == self || step.infinite?
+      block.call(i) if step > 0 && i <= (num||i) || step < 0 && i >= (num||-i)
+    elsif num == nil
       while true
         block.call(i)
         i += step
       end
-      return self
-    end
-    if step > 0
+    elsif step > 0
       while i <= num
         block.call(i)
         i += step

test/t/numeric.rb

 ##
 # Numeric ISO Test
 
+def  assert_step(exp, receiver, args, inf: false)
+  act = []
+  ret = receiver.step(*args) do |i|
+    act << i
+    break if inf && exp.size == act.size
+  end
+  expr = "#{receiver.inspect}.step(#{args.map(&:inspect).join(', ')})"
+  assert do
+    assert_true(exp.eql?(act), "#{expr}: counters", assertion_diff(exp, act))
+    assert_same(receiver, ret, "#{expr}: return value") unless inf
+  end
+end
+
 assert('Numeric', '15.2.7') do
   assert_equal(Class, Numeric.class)
 end
@@ -42,31 +55,60 @@ assert('Numeric#**') do
 end
 
 assert('Numeric#step') do
-  assert_step = ->(exp, receiver, args) do
-    inf = !args[0]
-    act = []
-    ret = receiver.step(*args) do |i|
-      act << i
-      break if inf && exp.size == act.size
-    end
-    expr = "#{receiver.inspect}.step(#{args.map(&:inspect).join(', ')})"
-    assert_true(exp.eql?(act), "#{expr}: counters", assertion_diff(exp, act))
-    assert_same(receiver, ret, "#{expr}: return value") unless inf
-  end
-
   assert_raise(ArgumentError) { 1.step(2, 0) { break } }
-  assert_step.([2, 3, 4], 2, [4])
-  assert_step.([10, 8, 6, 4, 2], 10, [1, -2])
-  assert_step.([], 2, [1, 3])
-  assert_step.([], -2, [-1, -3])
-  assert_step.([10, 11, 12, 13], 10, [])
-  assert_step.([10, 7, 4], 10, [nil, -3])
+  assert_step([2, 3, 4], 2, [4])
+  assert_step([10, 8, 6, 4, 2], 10, [1, -2])
+  assert_step([], 2, [1, 3])
+  assert_step([], -2, [-1, -3])
+  assert_step([10, 11, 12, 13], 10, [], inf: true)
+  assert_step([10, 7, 4], 10, [nil, -3], inf: true)
 
   skip unless Object.const_defined?(:Float)
+  inf = Float::INFINITY
   assert_raise(ArgumentError) { 1.step(2, 0.0) { break } }
-  assert_step.([2.0, 3.0, 4.0], 2, [4.0])
-  assert_step.([7.0, 4.0, 1.0, -2.0], 7, [-4, -3.0])
-  assert_step.([2.0, 3.0, 4.0], 2.0, [4])
-  assert_step.([10.0, 11.0, 12.0, 13.0], 10.0, [])
-  assert_step.([10.0, 7.0, 4.0], 10, [nil, -3.0])
+  assert_step([2.0, 3.0, 4.0], 2, [4.0])
+  assert_step([7.0, 4.0, 1.0, -2.0], 7, [-4, -3.0])
+  assert_step([2.0, 3.0, 4.0], 2.0, [4])
+  assert_step([10.0, 11.0, 12.0, 13.0], 10.0, [], inf: true)
+  assert_step([10.0, 7.0, 4.0], 10, [nil, -3.0], inf: true)
+  assert_step([1.0], 1, [nil, inf])
+  assert_step([1.0], 1, [nil, -inf])
+  assert_step([1.0], 1, [3, inf])
+  assert_step([], 1, [-3, inf])
+  assert_step([], 1, [3, -inf])
+  assert_step([1.0], 1, [-3, -inf])
+  assert_step([1.0], 1, [inf, inf])
+  assert_step([], 1, [inf, -inf])
+  assert_step([], 1, [-inf, inf])
+  assert_step([1.0], 1, [-inf, -inf])
+  assert_step([], inf, [2])
+  assert_step([], inf, [-2])
+  assert_step([], inf, [2, 3])
+  assert_step([inf, inf, inf], inf, [2, -3], inf: true)
+  assert_step([], inf, [2, inf])
+  assert_step([inf], inf, [2, -inf])
+  assert_step([], inf, [-2, inf])
+  assert_step([inf], inf, [-2, -inf])
+  assert_step([], inf, [-2, 3])
+  assert_step([inf, inf, inf], inf, [-2, -3], inf: true)
+  assert_step([inf], inf, [inf])
+  assert_step([], inf, [-inf])
+  assert_step([inf], inf, [inf, inf])
+  assert_step([inf], inf, [inf, -inf])
+  assert_step([inf], inf, [-inf, -inf])
+  assert_step([-inf, -inf, -inf], -inf, [2], inf: true)
+  assert_step([-inf, -inf, -inf], -inf, [-2], inf: true)
+  assert_step([-inf, -inf, -inf], -inf, [2, 3], inf: true)
+  assert_step([], -inf, [2, -3])
+  assert_step([-inf], -inf, [2, inf])
+  assert_step([], -inf, [2, -inf])
+  assert_step([-inf], -inf, [-2, inf])
+  assert_step([], -inf, [-2, -inf])
+  assert_step([-inf, -inf, -inf], -inf, [-2, 3], inf: true)
+  assert_step([], -inf, [-2, -3])
+  assert_step([-inf, -inf, -inf], -inf, [inf], inf: true)
+  assert_step([-inf], -inf, [-inf])
+  assert_step([-inf], -inf, [inf, inf])
+  assert_step([], -inf, [inf, -inf])
+  assert_step([-inf], -inf, [-inf, -inf])
 end