libutil: allow construction of sources from generators

Change-Id: I78ff8d0720f06bce731e26d5e1c53b1382bbd589

1 files changed, 21 insertions, 0 deletions

diff --git a/tests/unit/libutil/serialise.cc b/tests/unit/libutil/serialise.cc
index 78882ad2c..4fe010af8 100644
--- a/tests/unit/libutil/serialise.cc
+++ b/tests/unit/libutil/serialise.cc
@@ -214,4 +214,25 @@ TEST(WireFormatGenerator, exampleMessage)
             }));
 }
 
+TEST(GeneratorSource, works)
+{
+    GeneratorSource src = []() -> Generator<Bytes> {
+        co_yield std::span{"", 0};
+        co_yield std::span{"a", 1};
+        co_yield std::span{"", 0};
+        co_yield std::span{"bcd", 3};
+        co_yield std::span{"", 0};
+    }();
+
+    char buf[2];
+    ASSERT_EQ(src.read(buf, sizeof(buf)), 1);
+    ASSERT_EQ(buf[0], 'a');
+    ASSERT_EQ(src.read(buf, sizeof(buf)), 2);
+    ASSERT_EQ(buf[0], 'b');
+    ASSERT_EQ(buf[1], 'c');
+    ASSERT_EQ(src.read(buf, sizeof(buf)), 1);
+    ASSERT_EQ(buf[0], 'd');
+    ASSERT_THROW(src.read(buf, sizeof(buf)), EndOfFile);
+}
+
 }