Add whitespaceOptions: colonBraceSameLine to settings

include/json/value.h

@@ -124,6 +124,23 @@ enum CommentPlacement {
   numberOfCommentPlacement
 };
 
+enum WhitespaceOptions {
+  colonBraceSameLine = 1 << 0, ///< braces just after colons on the same line
+};
+inline WhitespaceOptions operator|(
+  WhitespaceOptions left, WhitespaceOptions right) {
+    return static_cast<WhitespaceOptions>(static_cast<int>(left) | static_cast<int>(right));
+}
+inline WhitespaceOptions& operator|=(
+  WhitespaceOptions& left, WhitespaceOptions right) {
+    left = left | right;
+    return left;
+}
+inline WhitespaceOptions operator&(
+  WhitespaceOptions left, WhitespaceOptions right) {
+    return static_cast<WhitespaceOptions>(static_cast<int>(left) & static_cast<int>(right));
+}
+
 /** \brief Type of precision for formatting of real values.
  */
 enum PrecisionType {

include/json/writer.h

@@ -94,25 +94,28 @@ class JSON_API StreamWriterBuilder : public StreamWriter::Factory {
   /** Configuration of this builder.
    *  Available settings (case-sensitive):
    *  - "commentStyle": "None" or "All"
-   *  - "indentation":  "<anything>".
-   *  - Setting this to an empty string also omits newline characters.
+   *  - "indentation": "<anything>".
+   *      Setting this to an empty string also omits newline characters.
    *  - "enableYAMLCompatibility": false or true
    *  - slightly change the whitespace around colons
+   *  - "whitespaceOptions": array of any combination of the following:
+   *      "colonBraceSameLine" - when an object or an array appears as a value
+   *        inside an object, keep the opening brace on the same line
    *  - "dropNullPlaceholders": false or true
-   *  - Drop the "null" string from the writer's output for nullValues.
-   *    Strictly speaking, this is not valid JSON. But when the output is being
-   *    fed to a browser's JavaScript, it makes for smaller output and the
-   *    browser can handle the output just fine.
+   *      Drop the "null" string from the writer's output for nullValues.
+   *      Strictly speaking, this is not valid JSON. But when the output is being
+   *      fed to a browser's JavaScript, it makes for smaller output and the
+   *      browser can handle the output just fine.
    *  - "useSpecialFloats": false or true
-   *  - If true, outputs non-finite floating point values in the following way:
-   *    NaN values as "NaN", positive infinity as "Infinity", and negative
-   *  infinity as "-Infinity".
+   *      If true, outputs non-finite floating point values in the following way:
+   *      NaN values as "NaN", positive infinity as "Infinity", and negative
+   *      infinity as "-Infinity".
    *  - "precision": int
-   *  - Number of precision digits for formatting of real values.
+   *      Number of precision digits for formatting of real values.
    *  - "precisionType": "significant"(default) or "decimal"
-   *  - Type of precision for formatting of real values.
+   *      Type of precision for formatting of real values.
    *  - "emitUTF8": false or true
-   *  - If true, outputs raw UTF8 strings instead of escaping them.
+   *      If true, outputs raw UTF8 strings instead of escaping them.
 
    *  You can examine 'settings_` yourself
    *  to see the defaults. You can also write and read them just like any

src/lib_json/json_writer.cpp

@@ -883,9 +883,10 @@ struct CommentStyle {
 struct BuiltStyledStreamWriter : public StreamWriter {
   BuiltStyledStreamWriter(String indentation, CommentStyle::Enum cs,
                           String colonSymbol, String nullSymbol,
-                          String endingLineFeedSymbol, bool useSpecialFloats,
-                          bool emitUTF8, unsigned int precision,
-                          PrecisionType precisionType);
+                          String endingLineFeedSymbol,
+                          WhitespaceOptions whitespaceOptions,
+                          bool useSpecialFloats, bool emitUTF8,
+                          unsigned int precision, PrecisionType precisionType);
   int write(Value const& root, OStream* sout) override;
 
 private:
@@ -911,6 +912,7 @@ struct BuiltStyledStreamWriter : public StreamWriter {
   String colonSymbol_;
   String nullSymbol_;
   String endingLineFeedSymbol_;
+  WhitespaceOptions whitespaceOptions_;
   bool addChildValues_ : 1;
   bool indented_ : 1;
   bool useSpecialFloats_ : 1;
@@ -920,11 +922,13 @@ struct BuiltStyledStreamWriter : public StreamWriter {
 };
 BuiltStyledStreamWriter::BuiltStyledStreamWriter(
     String indentation, CommentStyle::Enum cs, String colonSymbol,
-    String nullSymbol, String endingLineFeedSymbol, bool useSpecialFloats,
-    bool emitUTF8, unsigned int precision, PrecisionType precisionType)
+    String nullSymbol, String endingLineFeedSymbol,
+    WhitespaceOptions whitespaceOptions, bool useSpecialFloats, bool emitUTF8,
+    unsigned int precision, PrecisionType precisionType)
     : rightMargin_(74), indentation_(std::move(indentation)), cs_(cs),
       colonSymbol_(std::move(colonSymbol)), nullSymbol_(std::move(nullSymbol)),
       endingLineFeedSymbol_(std::move(endingLineFeedSymbol)),
+      whitespaceOptions_(whitespaceOptions),
       addChildValues_(false), indented_(false),
       useSpecialFloats_(useSpecialFloats), emitUTF8_(emitUTF8),
       precision_(precision), precisionType_(precisionType) {}
@@ -991,7 +995,11 @@ void BuiltStyledStreamWriter::writeValue(Value const& value) {
         writeWithIndent(
             valueToQuotedStringN(name.data(), name.length(), emitUTF8_));
         *sout_ << colonSymbol_;
+        if (whitespaceOptions_ & WhitespaceOptions::colonBraceSameLine)
+          indented_ = true;
         writeValue(childValue);
+        if (whitespaceOptions_ & WhitespaceOptions::colonBraceSameLine)
+          indented_ = false;
         if (++it == members.end()) {
           writeCommentAfterValueOnSameLine(childValue);
           break;
@@ -1169,6 +1177,7 @@ StreamWriter* StreamWriterBuilder::newStreamWriter() const {
   const String cs_str = settings_["commentStyle"].asString();
   const String pt_str = settings_["precisionType"].asString();
   const bool eyc = settings_["enableYAMLCompatibility"].asBool();
+  const Value& wo_array = settings_["whitespaceOptions"];
   const bool dnp = settings_["dropNullPlaceholders"].asBool();
   const bool usf = settings_["useSpecialFloats"].asBool();
   const bool emitUTF8 = settings_["emitUTF8"].asBool();
@@ -1195,6 +1204,15 @@ StreamWriter* StreamWriterBuilder::newStreamWriter() const {
   } else if (indentation.empty()) {
     colonSymbol = ":";
   }
+  WhitespaceOptions whitespaceOptions = static_cast<WhitespaceOptions>(0);
+  for (auto wi = wo_array.begin(); wi != wo_array.end(); ++wi) {
+    const String& option = wi->asString();
+    if (option == "colonBraceSameLine") {
+      whitespaceOptions |= WhitespaceOptions::colonBraceSameLine;
+    } else {
+      throwRuntimeError("unknown option passed to whitespaceOptions");
+    }
+  }
   String nullSymbol = "null";
   if (dnp) {
     nullSymbol.clear();
@@ -1203,15 +1221,16 @@ StreamWriter* StreamWriterBuilder::newStreamWriter() const {
     pre = 17;
   String endingLineFeedSymbol;
   return new BuiltStyledStreamWriter(indentation, cs, colonSymbol, nullSymbol,
-                                     endingLineFeedSymbol, usf, emitUTF8, pre,
-                                     precisionType);
+                                     endingLineFeedSymbol, whitespaceOptions,
+                                     usf, emitUTF8, pre, precisionType);
 }
 
 bool StreamWriterBuilder::validate(Json::Value* invalid) const {
   static const auto& valid_keys = *new std::set<String>{
       "indentation",
       "commentStyle",
       "enableYAMLCompatibility",
+      "whitespaceOptions",
       "dropNullPlaceholders",
       "useSpecialFloats",
       "emitUTF8",
@@ -1239,6 +1258,7 @@ void StreamWriterBuilder::setDefaults(Json::Value* settings) {
   (*settings)["commentStyle"] = "All";
   (*settings)["indentation"] = "\t";
   (*settings)["enableYAMLCompatibility"] = false;
+  (*settings)["whitespaceOptions"] = Value(arrayValue);
   (*settings)["dropNullPlaceholders"] = false;
   (*settings)["useSpecialFloats"] = false;
   (*settings)["emitUTF8"] = false;