Properly handle impossible cases in (not_)between

Fixes rails#43521

Author: fschwahn

activerecord/lib/arel/predications.rb

@@ -39,7 +39,11 @@ def between(other)
         self.in([])
       elsif open_ended?(other.begin)
         if open_ended?(other.end)
-          not_in([])
+          if infinity?(other.begin) == 1 || infinity?(other.end) == -1
+            self.in([])
+          else
+            not_in([])
+          end
         elsif other.exclude_end?
           lt(other.end)
         else
@@ -80,7 +84,11 @@ def not_between(other)
         not_in([])
       elsif open_ended?(other.begin)
         if open_ended?(other.end)
-          self.in([])
+          if infinity?(other.begin) == 1 || infinity?(other.end) == -1
+            not_in([])
+          else
+            self.in([])
+          end
         elsif other.exclude_end?
           gteq(other.end)
         else

activerecord/test/cases/arel/attributes/attribute_test.rb

@@ -668,6 +668,20 @@ class AttributeTest < Arel::Spec
           )
         end
 
+        it "can be constructed with an endless range starting from Infinity" do
+          attribute = Attribute.new nil, nil
+          node = attribute.between(::Float::INFINITY..)
+
+          _(node).must_equal Nodes::In.new(attribute, [])
+        end
+
+        it "can be constructed with a beginless range ending in -Infinity" do
+          attribute = Attribute.new nil, nil
+          node = attribute.between(..-::Float::INFINITY)
+
+          _(node).must_equal Nodes::In.new(attribute, [])
+        end
+
         it "can be constructed with an exclusive range" do
           attribute = Attribute.new nil, nil
           node = attribute.between(0...3)
@@ -877,6 +891,20 @@ class AttributeTest < Arel::Spec
           )
         end
 
+        it "can be constructed with an endless range starting from Infinity" do
+          attribute = Attribute.new nil, nil
+          node = attribute.not_between(::Float::INFINITY..)
+
+          _(node).must_equal Nodes::NotIn.new(attribute, [])
+        end
+
+        it "can be constructed with a beginless range ending in -Infinity" do
+          attribute = Attribute.new nil, nil
+          node = attribute.not_between(..-::Float::INFINITY)
+
+          _(node).must_equal Nodes::NotIn.new(attribute, [])
+        end
+
         it "can be constructed with an exclusive range" do
           attribute = Attribute.new nil, nil
           node = attribute.not_between(0...3)