[GH #1612]: Fix missing String#to_d definition in BigDecimal.

PullRequest: truffleruby/686

Author: nirvdrum

lib/mri/bigdecimal/util.rb

@@ -66,6 +66,14 @@ class String
   #
   # See also BigDecimal::new.
   #
+  # TruffleRuby: MRI defines this method in C. We define it in Ruby for simplicity & clarity.
+  def to_d
+    begin
+      BigDecimal(self)
+    rescue ArgumentError
+      BigDecimal(0)
+    end
+  end
 end
 
 

spec/ruby/library/bigdecimal/util_spec.rb

@@ -0,0 +1,45 @@
+require_relative '../../spec_helper'
+require 'bigdecimal'
+require 'bigdecimal/util'
+
+describe "BigDecimal's util method definitions" do
+
+  describe "#to_d" do
+
+    it "should define #to_d on Integer" do
+      42.to_d.should == BigDecimal(42)
+    end
+
+    it "should define #to_d on Float" do
+      0.5.to_d.should == BigDecimal(0.5, Float::DIG)
+      1.234.to_d(2).should == BigDecimal(1.234, 2)
+    end
+
+    it "should define #to_d on String" do
+      "0.5".to_d.should == BigDecimal(0.5, Float::DIG)
+      "45.67 degrees".to_d.should == BigDecimal(45.67, Float::DIG)
+    end
+
+    it "should define #to_d on BigDecimal" do
+      bd = BigDecimal("3.14")
+      bd.to_d.should equal(bd)
+    end
+
+    it "should define #to_d on Rational" do
+      Rational(22, 7).to_d(3).should == BigDecimal(3.14, 3)
+    end
+
+    it "should define #to_d on nil" do
+      nil.to_d.should == BigDecimal(0)
+    end
+
+  end
+
+  describe "#to_digits" do
+
+    it "should define #to_digits on BigDecimal" do
+      BigDecimal("3.14").to_digits.should == "3.14"
+    end
+
+  end
+end

spec/tags/library/bigdecimal/BigDecimal_tags.txt

@@ -1,5 +1,4 @@
 slow:BigDecimal is not defined unless it is required
 fails:Kernel#BigDecimal raises ArgumentError for invalid strings
-fails:BigDecimal is not defined unless it is required
 fails:Kernel#BigDecimal does not ignores trailing garbage
 fails:Kernel#BigDecimal process underscores as Float()