Add special logging for infinite times (#29158)

src/core/lib/gprpp/time.cc

@@ -155,6 +155,12 @@ gpr_timespec Timestamp::as_timespec(gpr_clock_type clock_type) const {
 }
 
 std::string Timestamp::ToString() const {
+  if (millis_ == std::numeric_limits<int64_t>::max()) {
+    return "@∞";
+  }
+  if (millis_ == std::numeric_limits<int64_t>::min()) {
+    return "@-∞";
+  }
   return "@" + std::to_string(millis_) + "ms";
 }
 
@@ -167,6 +173,12 @@ Duration Duration::FromTimespec(gpr_timespec t) {
 }
 
 std::string Duration::ToString() const {
+  if (millis_ == std::numeric_limits<int64_t>::max()) {
+    return "∞";
+  }
+  if (millis_ == std::numeric_limits<int64_t>::min()) {
+    return "-∞";
+  }
   return std::to_string(millis_) + "ms";
 }
 

test/core/gprpp/time_test.cc

@@ -35,6 +35,8 @@ TEST(TimestampTest, Infinities) {
 TEST(TimestampTest, ToString) {
   EXPECT_EQ(Timestamp::FromMillisecondsAfterProcessEpoch(42).ToString(),
             "@42ms");
+  EXPECT_EQ(Timestamp::InfFuture().ToString(), "@∞");
+  EXPECT_EQ(Timestamp::InfPast().ToString(), "@-∞");
 }
 
 TEST(DurationTest, Empty) { EXPECT_EQ(Duration(), Duration::Zero()); }
@@ -78,6 +80,12 @@ TEST(DurationTest, FromTimespan) {
             Duration::Milliseconds(1234));
 }
 
+TEST(DurationTest, ToString) {
+  EXPECT_EQ(Duration::Milliseconds(42).ToString(), "42ms");
+  EXPECT_EQ(Duration::Infinity().ToString(), "∞");
+  EXPECT_EQ(Duration::NegativeInfinity().ToString(), "-∞");
+}
+
 }  // namespace testing
 }  // namespace grpc_core