[Truffle] Fix Float#to_s.

jruby · Mar 9, 2016 · dc83f5d · dc83f5d
1 parent 5b08612
commit dc83f5d
Showing 2 changed files with 34 additions and 23 deletions.
diff --git a/truffle/src/main/java/org/jruby/truffle/core/numeric/FloatNodes.java b/truffle/src/main/java/org/jruby/truffle/core/numeric/FloatNodes.java
@@ -17,6 +17,7 @@
 import com.oracle.truffle.api.object.DynamicObject;
 import com.oracle.truffle.api.profiles.ConditionProfile;
 import com.oracle.truffle.api.source.SourceSection;
+import java.util.Locale;
 import org.jcodings.specific.USASCIIEncoding;
 import org.jruby.runtime.Visibility;
 import org.jruby.truffle.RubyContext;
@@ -722,17 +723,45 @@ public double toF(double value) {
 
     }
 
-    @CoreMethod(names = { "java_to_s" }, visibility = Visibility.PRIVATE)
-    public abstract static class JavaToSNode extends CoreMethodArrayArgumentsNode {
+    @CoreMethod(names = { "to_s", "inspect" })
+    public abstract static class ToSNode extends CoreMethodArrayArgumentsNode {
 
-        public JavaToSNode(RubyContext context, SourceSection sourceSection) {
+        public ToSNode(RubyContext context, SourceSection sourceSection) {
             super(context, sourceSection);
         }
 
         @TruffleBoundary
         @Specialization
-        public DynamicObject javaToS(double value) {
-            return create7BitString(String.format("%.15g", value), USASCIIEncoding.INSTANCE);
+        public DynamicObject toS(double value) {
+            if (Double.isInfinite(value) || Double.isNaN(value)) {
+                return create7BitString(Double.toString(value), USASCIIEncoding.INSTANCE);
+            }
+
+            String str = String.format(Locale.ENGLISH, "%.15g", value);
+
+            // If no dot, add one to show it's a floating point number
+            if (str.indexOf('.') == -1) {
+                assert str.indexOf('e') == -1;
+                str += ".0";
+            }
+
+            final int e = str.indexOf('e');
+            final boolean hasE = e != -1;
+
+            // Remove trailing zeroes
+            final int start = hasE ? e : str.length();
+            int i = start;
+            while (i > 0 && str.charAt(i - 1) == '0') {
+                i--;
+            }
+
+            // But keep at least one after the dot
+            if (i > 0 && str.charAt(i - 1) == '.') {
+                i++;
+            }
+
+            final String formatted = str.substring(0, i) + str.substring(start, str.length());
+            return create7BitString(formatted, USASCIIEncoding.INSTANCE);
         }
 
     }

diff --git a/truffle/src/main/ruby/core/float.rb b/truffle/src/main/ruby/core/float.rb
@@ -74,22 +74,4 @@ def equal_fallback(other)
 
   private :equal_fallback
 
-  # TODO (pitr 27-Nov-2015): needs better implementation
-  def to_s
-    return format('%g', self) if infinite? || nan?
-
-    str = java_to_s
-
-    # remove extra zeroes
-    str.gsub! /^(-?)(\d+\.((\d*[1-9])|0))0+/, '\1\2'
-
-    return str if str =~ /e/
-
-    # add trailing zero if none
-    str << '.0' unless str =~ /\./
-    str
-  end
-
-  alias_method :inspect, :to_s
-
 end