Bug 608915 - part 1 - extend ToPrecision to tell use whether exponential notation was used; r=Waldo

mfbt/double-conversion/ToPrecision-exponential.patch

@@ -0,0 +1,35 @@
+1e7bf0c636b8cca54dd83456a0f8fa219343e2a1 Bug 608195 - part 2 - extend ToPrecision to tell use whether exponential notation was used
+diff --git a/mfbt/double-conversion/double-conversion.cc b/mfbt/double-conversion/double-conversion.cc
+index febba6c..394b6a0 100644
+--- a/mfbt/double-conversion/double-conversion.cc
++++ b/mfbt/double-conversion/double-conversion.cc
+@@ -283,7 +283,9 @@ bool DoubleToStringConverter::ToExponential(
+ 
+ bool DoubleToStringConverter::ToPrecision(double value,
+                                           int precision,
++                                          bool* used_exponential_notation,
+                                           StringBuilder* result_builder) const {
++  *used_exponential_notation = false;
+   if (Double(value).IsSpecial()) {
+     return HandleSpecialValues(value, result_builder);
+   }
+@@ -325,6 +327,7 @@ bool DoubleToStringConverter::ToPrecision(double value,
+       decimal_rep[i] = '0';
+     }
+ 
++    *used_exponential_notation = true;
+     CreateExponentialRepresentation(decimal_rep,
+                                     precision,
+                                     exponent,
+diff --git a/mfbt/double-conversion/double-conversion.h b/mfbt/double-conversion/double-conversion.h
+index 0900ba0..957575c 100644
+--- a/mfbt/double-conversion/double-conversion.h
++++ b/mfbt/double-conversion/double-conversion.h
+@@ -270,6 +270,7 @@ class DoubleToStringConverter {
+   // exponent character, the exponent's sign, and at most 3 exponent digits).
+   MFBT_API bool ToPrecision(double value,
+                    int precision,
++                   bool* used_exponential_notation,
+                    StringBuilder* result_builder) const;
+ 
+   enum DtoaMode {

mfbt/double-conversion/double-conversion.cc

@@ -283,7 +283,9 @@ bool DoubleToStringConverter::ToExponential(
 
 bool DoubleToStringConverter::ToPrecision(double value,
                                           int precision,
+                                          bool* used_exponential_notation,
                                           StringBuilder* result_builder) const {
+  *used_exponential_notation = false;
   if (Double(value).IsSpecial()) {
     return HandleSpecialValues(value, result_builder);
   }
@@ -325,6 +327,7 @@ bool DoubleToStringConverter::ToPrecision(double value,
       decimal_rep[i] = '0';
     }
 
+    *used_exponential_notation = true;
     CreateExponentialRepresentation(decimal_rep,
                                     precision,
                                     exponent,

mfbt/double-conversion/double-conversion.h

@@ -270,6 +270,7 @@ class DoubleToStringConverter {
   // exponent character, the exponent's sign, and at most 3 exponent digits).
   MFBT_API bool ToPrecision(double value,
                    int precision,
+                   bool* used_exponential_notation,
                    StringBuilder* result_builder) const;
 
   enum DtoaMode {

mfbt/double-conversion/update.sh

@@ -20,3 +20,4 @@ patch -p3 < add-mfbt-api-markers.patch
 patch -p3 < use-StandardInteger.patch
 patch -p3 < use-mozilla-assertions.patch
 patch -p3 < use-static_assert.patch
+patch -p3 < ToPrecision-exponential.patch