Get rid of TraceOptions::SetSampled() in favor of WithSampling(). (#285)

Author: g-easy

opencensus/trace/internal/running_span_store_test.cc

@@ -38,13 +38,6 @@
 namespace opencensus {
 namespace trace {
 
-class SpanTestPeer {
- public:
-  static void SetSampled(TraceOptions* opts, bool is_sampled) {
-    opts->SetSampled(is_sampled);
-  }
-};
-
 namespace exporter {
 class RunningSpanStoreImplTestPeer {
  public:

opencensus/trace/internal/span.cc

@@ -89,7 +89,7 @@ class SpanGenerator {
                 parent_ctx, has_remote_parent, trace_id, span_id, name,
                 options.parent_links);
       }
-      trace_options.SetSampled(should_sample);
+      trace_options = trace_options.WithSampling(should_sample);
     }
     SpanContext context(trace_id, span_id, trace_options);
     SpanImpl* impl = nullptr;

opencensus/trace/internal/span_test.cc

@@ -35,10 +35,6 @@ class SpanTestPeer {
     return span->span_impl_for_test()->parent_span_id();
   }
 
-  static void SetSampled(TraceOptions* opts, bool is_sampled) {
-    opts->SetSampled(is_sampled);
-  }
-
   static exporter::SpanData ToSpanData(Span* span) {
     return span->span_impl_for_test()->ToSpanData();
   }
@@ -291,10 +287,8 @@ TEST(SpanTest, ChildInheritsTraceOption) {
                                   9, 10, 11, 12, 13, 14, 15, 16};
   constexpr uint8_t span_id[] = {1, 0, 0, 0, 0, 0, 0, 11};
   // Create a parent context with TraceOptions set to sampled.
-  TraceOptions trace_options;
-  SpanTestPeer::SetSampled(&trace_options, true);
-  SpanContext parent_ctx1{TraceId(trace_id), SpanId(span_id),
-                          TraceOptions(trace_options)};
+  TraceOptions trace_options = TraceOptions().WithSampling(true);
+  SpanContext parent_ctx1{TraceId(trace_id), SpanId(span_id), trace_options};
 
   // Create a child Span with default sampling.
   auto span1 = Span::StartSpanWithRemoteParent("Span1", parent_ctx1);

opencensus/trace/internal/trace_options.cc

@@ -42,14 +42,11 @@ std::string TraceOptions::ToHex() const {
 
 void TraceOptions::CopyTo(uint8_t* buf) const { memcpy(buf, rep_, kSize); }
 
-void TraceOptions::SetSampled(bool is_sampled) {
-  rep_[0] = (rep_[0] & ~kIsSampled) | (is_sampled ? kIsSampled : 0);
-}
-
 TraceOptions TraceOptions::WithSampling(bool is_sampled) const {
-  TraceOptions child = *this;
-  child.SetSampled(is_sampled);
-  return child;
+  uint8_t buf[kSize];
+  CopyTo(buf);
+  buf[0] = (buf[0] & ~kIsSampled) | (is_sampled ? kIsSampled : 0);
+  return TraceOptions(buf);
 }
 
 }  // namespace trace

opencensus/trace/internal/trace_options_test.cc

@@ -19,38 +19,31 @@
 namespace opencensus {
 namespace trace {
 
-class SpanTestPeer {
- public:
-  static void SetSampled(TraceOptions* opts, bool is_sampled) {
-    opts->SetSampled(is_sampled);
-  }
-};
-
 namespace {
 
 TEST(TraceOptionsTest, SetSampled) {
   TraceOptions opts;
 
   EXPECT_EQ("00", opts.ToHex());
   EXPECT_FALSE(opts.IsSampled());
-  SpanTestPeer::SetSampled(&opts, true);
+  opts = opts.WithSampling(true);
   EXPECT_EQ("01", opts.ToHex());
   EXPECT_TRUE(opts.IsSampled());
-  SpanTestPeer::SetSampled(&opts, false);
+  opts = opts.WithSampling(false);
+  EXPECT_EQ("00", opts.ToHex());
   EXPECT_FALSE(opts.IsSampled());
 }
 
 TEST(TraceOptionsTest, Comparison) {
   TraceOptions a;
   TraceOptions b;
   EXPECT_EQ(a, b);
-  SpanTestPeer::SetSampled(&a, true);
+  b = b.WithSampling(true);
   EXPECT_FALSE(a == b);
 }
 
 TEST(TraceOptionsTest, CopyAndSetSampled) {
-  TraceOptions a;
-  SpanTestPeer::SetSampled(&a, true);
+  TraceOptions a = TraceOptions().WithSampling(true);
   TraceOptions b = a.WithSampling(false);
   EXPECT_TRUE(a.IsSampled());
   EXPECT_FALSE(b.IsSampled());

opencensus/trace/trace_options.h

@@ -55,12 +55,6 @@ class TraceOptions final {
   TraceOptions WithSampling(bool is_sampled) const;
 
  private:
-  friend class SpanGenerator;
-  friend class SpanTestPeer;
-
-  // Only StartSpan should be calling this.
-  void SetSampled(bool is_sampled);
-
   uint8_t rep_[kSize];
 };