From 9b327a9bba0c95119c400cbd53f14804905b906d Mon Sep 17 00:00:00 2001
From: Simon Cruanes <simon.cruanes.2007@m4x.org>
Date: Sat, 4 Apr 2026 03:11:16 +0000
Subject: [PATCH] tests for trace-state

---
 tests/core/test_trace_context.expected | 15 +++++++
 tests/core/test_trace_context.ml       | 56 ++++++++++++++++++++++++++
 2 files changed, 71 insertions(+)

diff --git a/tests/core/test_trace_context.expected b/tests/core/test_trace_context.expected
index 21b56778..b6741695 100644
--- a/tests/core/test_trace_context.expected
+++ b/tests/core/test_trace_context.expected
@@ -29,3 +29,18 @@ Trace_context.Traceparent.of_value "00-4bf92f3577b34da6a3ce929d0e0e4736-00f067aa
 
 Trace_context.Traceparent.to_value trace_id:"4bf92f3577b34da6a3ce929d0e0e4736" parent_id:"00f067aa0ba902b7":
   "00-4bf92f3577b34da6a3ce929d0e0e4736-00f067aa0ba902b7-00"
+
+of_w3c_string "" -> Ok "" (len=0)
+of_w3c_string "congo=t61rcwkgmze" -> Ok "congo=t61rcwkgmze" (len=17)
+of_w3c_string "congo=t61rcwkgmze,rojo=00f067aa0ba902b7" -> Ok "congo=t61rcwkgmze,rojo=00f067aa0ba902b7" (len=39)
+of_w3c_string "  vendor=value  " -> Ok "vendor=value" (len=12)
+of_w3c_string "bad key=value" -> Ok "" (len=0)
+of_w3c_string "key=val,=bad,other=fine" -> Ok "key=val,other=fine" (len=18)
+
+set/replace: "vendor=new,other=xyz"
+after delete: "vendor=new"
+get vendor: "new"
+
+Tracestate.name = "tracestate"
+of_w3c_string round-trip: "a=b,c=d"
+of_w3c_string empty: ""
diff --git a/tests/core/test_trace_context.ml b/tests/core/test_trace_context.ml
index 18cca5a5..98c8257f 100644
--- a/tests/core/test_trace_context.ml
+++ b/tests/core/test_trace_context.ml
@@ -54,3 +54,59 @@ let () =
   test_to_value
     (Trace_id.of_hex "4bf92f3577b34da6a3ce929d0e0e4736")
     (Span_id.of_hex "00f067aa0ba902b7")
+
+let () = print_endline ""
+
+(* Trace_state tests *)
+
+let test_trace_state_rt str =
+  let open Format in
+  let result = Trace_state.of_w3c_string str in
+  match result with
+  | Ok ts ->
+    printf "of_w3c_string %S -> Ok %S (len=%d)@." str
+      (Trace_state.to_w3c_string ts)
+      (Trace_state.encoded_length ts)
+  | Error e -> printf "of_w3c_string %S -> Error %S@." str e
+
+let () = test_trace_state_rt ""
+
+let () = test_trace_state_rt "congo=t61rcwkgmze"
+
+let () = test_trace_state_rt "congo=t61rcwkgmze,rojo=00f067aa0ba902b7"
+
+let () = test_trace_state_rt "  vendor=value  "
+
+let () = test_trace_state_rt "bad key=value"
+
+let () = test_trace_state_rt "key=val,=bad,other=fine"
+
+let () = print_endline ""
+
+let test_trace_state_set () =
+  let ts = Trace_state.empty in
+  let ts = Trace_state.set ts "vendor" "abc" in
+  let ts = Trace_state.set ts "other" "xyz" in
+  let ts = Trace_state.set ts "vendor" "new" in
+  Format.printf "set/replace: %S@." (Trace_state.to_w3c_string ts);
+  let ts = Trace_state.delete ts "other" in
+  Format.printf "after delete: %S@." (Trace_state.to_w3c_string ts);
+  Format.printf "get vendor: %S@."
+    (Option.value ~default:"(none)" (Trace_state.get ts "vendor"))
+
+let () = test_trace_state_set ()
+
+let () = print_endline ""
+
+let test_tracestate_header () =
+  let module TS = Trace_context.Tracestate in
+  Format.printf "Tracestate.name = %S@." TS.name;
+  (match TS.of_w3c_string "a=b,c=d" with
+  | Ok ts ->
+    Format.printf "of_w3c_string round-trip: %S@." (TS.to_w3c_string ts)
+  | Error e -> Format.printf "of_w3c_string error: %S@." e);
+  match TS.of_w3c_string "" with
+  | Ok ts -> Format.printf "of_w3c_string empty: %S@." (TS.to_w3c_string ts)
+  | Error e -> Format.printf "of_w3c_string error: %S@." e
+
+let () = test_tracestate_header ()