Bka single line logs

Continuing !955 (closed)

src/ds/str-test.cpp

@@ -107,15 +107,7 @@ TEST_CASE("dsStr", TAGS) {
     y.xs.back().i = 0;
     y.enum_ = Enum::B;
 
-    CHECK(ds::str(y) == R"((
- x:(
-   i:8 c:f uc:9 s:hi)
- xs:((
-     i:8 c:f uc:9 s:hi)
-  ,(
-     c:f uc:9 s:hi)
-  ) enum_:b)
-)");
+    CHECK(ds::str(y) == R"({x:{i:8 c:f uc:9 s:hi} xs:({i:8 c:f uc:9 s:hi},{c:f uc:9 s:hi}) enum_:b})");
   }
 
   SECTION("(const char *) nullptr is serialized as (nullptr)") {

src/ds/str.h

@@ -104,8 +104,9 @@ template <typename T>
 struct StrReflect : boost::noncopyable {
   std::ostream& ostream;
   const T& x;
+  mutable bool first;
   int indent;
-  StrReflect(std::ostream& ostream, const T& x, int indent) : ostream(ostream), x(x), indent(indent + 1) {}
+  StrReflect(std::ostream& ostream, const T& x, int indent) : ostream(ostream), x(x), first(true), indent(indent + 1) {}
 
   template <typename MemberPtr, MemberPtr m>
   void operator()(const char* name) const {
@@ -115,7 +116,12 @@ struct StrReflect : boost::noncopyable {
     if (isDefaultInstance(value)) {
       return;
     }
-    ostream << ' ' << name << ':';
+    if (first) {
+      first = false;
+    } else {
+      ostream << ' ';
+    }
+    ostream << name << ':';
     Str<Member>::f(ostream, value, indent);
   }
 };
@@ -123,17 +129,9 @@ struct StrReflect : boost::noncopyable {
 template <typename T>
 struct Str<T, typename std::enable_if<ds::reflector<T>::is_defined::value>::type> {
   static inline void f(std::ostream& ostream, const T& x, int indent) {
-    // \n at the start and at the end of struct seem like good compromise
-    // between readability, consumed vertical space and code complexity
-    ostream << "(\n";
-    for (int i = 0; i < indent; i++) {
-      ostream << "  ";
-    }
+    ostream << "{";
     ds::reflector<T>::visit(StrReflect<T>(ostream, x, indent));
-    ostream << ")\n";
-    for (int i = 0; i < indent - 1; i++) {
-      ostream << "  ";
-    }
+    ostream << "}";
   }
 };