[core] add ability to stringify doubles that are integer with and without trailing ".0"

5 files changed, 18 insertions, 12 deletions

diff --git a/include/mbgl/util/string.hpp b/include/mbgl/util/string.hpp
index 13498ccb92..1cca386e21 100644
--- a/include/mbgl/util/string.hpp
+++ b/include/mbgl/util/string.hpp
@@ -49,9 +49,9 @@ inline std::string toString(uint8_t num) {
     return std::to_string(unsigned(num));
 }
 
-std::string toString(float);
-std::string toString(double);
-std::string toString(long double);
+std::string toString(float, bool decimal = false);
+std::string toString(double, bool decimal = false);
+std::string toString(long double, bool decimal = false);
 
 inline std::string toString(std::exception_ptr error) {
     assert(error);
diff --git a/src/mbgl/util/dtoa.cpp b/src/mbgl/util/dtoa.cpp
index fce1f122b7..934a78f7ab 100644
--- a/src/mbgl/util/dtoa.cpp
+++ b/src/mbgl/util/dtoa.cpp
@@ -13,12 +13,12 @@ namespace util {
 
 #if !defined(_WINDOWS)
 
-std::string dtoa(double value) {
+std::string dtoa(double value, bool decimal) {
     std::string data;
     data.resize(25);
     auto end = rapidjson::internal::dtoa(value, const_cast<char*>(data.data()));
     auto length = end - data.data();
-    if (length >= 3 && end[-1] == '0' && end[-2] == '.') {
+    if (!decimal && length >= 3 && end[-1] == '0' && end[-2] == '.') {
         // Remove trailing ".0" for integers
         length -= 2;
     }
diff --git a/src/mbgl/util/dtoa.hpp b/src/mbgl/util/dtoa.hpp
index e6b1659aa2..22aa925675 100644
--- a/src/mbgl/util/dtoa.hpp
+++ b/src/mbgl/util/dtoa.hpp
@@ -6,7 +6,7 @@
 namespace mbgl {
 namespace util {
 
-std::string dtoa(double value);
+std::string dtoa(double value, bool decimal = false);
 
 inline double stod(const std::string& str) {
     return ::strtod(str.c_str(), nullptr);
diff --git a/src/mbgl/util/string.cpp b/src/mbgl/util/string.cpp
index 4738209382..b20b3fb7ed 100644
--- a/src/mbgl/util/string.cpp
+++ b/src/mbgl/util/string.cpp
@@ -4,16 +4,17 @@
 namespace mbgl {
 namespace util {
 
-std::string toString(float num) {
-    return dtoa(num);
+std::string toString(float num, bool decimal) {
+    return dtoa(num, decimal);
 }
 
-std::string toString(double num) {
-    return dtoa(num);
+std::string toString(double num, bool decimal) {
+    return dtoa(num, decimal);
 }
 
-std::string toString(long double num) {
-    return dtoa(num);
+std::string toString(long double num, bool decimal) {
+    return dtoa(num, decimal);
+}
 }
 
 } // namespace util
diff --git a/test/util/string.test.cpp b/test/util/string.test.cpp
index 06e6ca9e9e..08e8e9f759 100644
--- a/test/util/string.test.cpp
+++ b/test/util/string.test.cpp
@@ -6,8 +6,13 @@ using namespace mbgl;
 
 TEST(ToString, FloatingPoint) {
     EXPECT_EQ("0", util::toString(0.0));
+    EXPECT_EQ("0.0", util::toString(0.0, true));
     EXPECT_EQ("1.33", util::toString(1.33));
+    EXPECT_EQ("1.33", util::toString(1.33, true));
     EXPECT_EQ("-1", util::toString(-1.0));
+    EXPECT_EQ("-1.0", util::toString(-1.0, true));
     EXPECT_EQ("12340000000", util::toString(12340000000.0));
+    EXPECT_EQ("12340000000.0", util::toString(12340000000.0, true));
     EXPECT_EQ("12340000000", util::toString(12340000000.0));
+    EXPECT_EQ("12340000000.0", util::toString(12340000000.0, true));
 }