Merge pull request #30 from bdunne/numeric_clamp

Extract Numeric#apply_min_max to #clamp

README.md

@@ -59,6 +59,8 @@ MoreCoreExtensions are a set of core extensions beyond those provided by ActiveS
 
 #### Numeric
 
+* core_ext/numeric/clamp.rb
+  * `#clamp` - Clamp a number to a minimum and/or maximum value
 * core_ext/numeric/math.rb
   * `#square` - Returns the square of a Numeric
 * core_ext/numeric/rounding.rb

lib/more_core_extensions/core_ext/numeric.rb

@@ -1,2 +1,3 @@
+require 'more_core_extensions/core_ext/numeric/clamp'
 require 'more_core_extensions/core_ext/numeric/math'
 require 'more_core_extensions/core_ext/numeric/rounding'

lib/more_core_extensions/core_ext/numeric/clamp.rb

@@ -0,0 +1,18 @@
+module MoreCoreExtensions
+  module NumericClamp
+    #
+    # Clamp a number to a minimum and/or maximum value.
+    #
+    #   8.clamp(nil, nil) #=> 8
+    #   8.clamp(9, nil)   #=> 9
+    #   8.clamp(nil, 6)   #=> 6
+    def clamp(min, max)
+      value = self
+      value = [value, min].max if min
+      value = [value, max].min if max
+      value
+    end
+  end
+end
+
+Numeric.send(:prepend, MoreCoreExtensions::NumericClamp)

spec/core_ext/numeric/clamp_spec.rb

@@ -0,0 +1,17 @@
+describe Numeric do
+  it "#clamp" do
+    expect(8.clamp(nil, nil)).to eq(8)
+    expect(8.clamp(3, nil)).to eq(8)
+    expect(8.clamp(13, nil)).to eq(13)
+    expect(8.clamp(nil, 6)).to eq(6)
+    expect(8.clamp(13, 16)).to eq(13)
+    expect(20.clamp(13, 16)).to eq(16)
+
+    expect(8.0.clamp(nil, nil)).to eq(8.0)
+    expect(8.0.clamp(3.0, nil)).to eq(8.0)
+    expect(8.0.clamp(13.0, nil)).to eq(13.0)
+    expect(8.0.clamp(nil, 6.0)).to eq(6.0)
+    expect(8.0.clamp(13.0, 16.0)).to eq(13.0)
+    expect(20.0.clamp(13.0, 16.0)).to eq(16.0)
+  end
+end