Sample primary repeat timeout

2 files changed, 53 insertions, 0 deletions

diff --git a/lua/clever_f/repeat_resolver.lua b/lua/clever_f/repeat_resolver.lua
index e246ef8..5e1dc41 100644
--- a/lua/clever_f/repeat_resolver.lua
+++ b/lua/clever_f/repeat_resolver.lua
@@ -18,6 +18,22 @@ local function fail(message, level)
   error(message, (level or 1) + 1)
 end
 
+local function is_nonnegative_integer(value)
+  return type(value) == "number"
+    and value >= 0
+    and value < math.huge
+    and value == math.floor(value)
+end
+
+local function require_policy(service)
+  if service ~= nil and (type(service) ~= "table"
+      or type(service.sample_timeouts) ~= "function")
+  then
+    fail("RepeatResolver policy must provide sample_timeouts", 3)
+  end
+  return service
+end
+
 local resolver_metatable = {
   __index = RepeatResolver,
   __newindex = function()
@@ -48,6 +64,7 @@ function RepeatResolver.new(options)
 
   local resolver = setmetatable({}, resolver_metatable)
   resolver_records[resolver] = {
+    policy = require_policy(options.policy or options.policy_service),
     state = state,
   }
   return resolver
@@ -77,6 +94,21 @@ end
 RepeatResolver.eligibility = RepeatResolver.decide
 RepeatResolver.resolve_eligibility = RepeatResolver.decide
 
+function RepeatResolver:sample_repeat_timeout_ms()
+  local service = resolver_records[self].policy
+  if service == nil then
+    fail("RepeatResolver requires a policy to sample repeat timeout", 2)
+  end
+  local sampled = service:sample_timeouts()
+  local timeout = type(sampled) == "table" and sampled.repeat_timeout_ms or nil
+  if not is_nonnegative_integer(timeout) then
+    fail("repeat_timeout_ms sample must be a nonnegative integer", 2)
+  end
+  return timeout
+end
+
+RepeatResolver.sample_repeat_timeout = RepeatResolver.sample_repeat_timeout_ms
+
 function M.new(options)
   return RepeatResolver.new(options)
 end
@@ -95,6 +127,10 @@ end
 
 M.eligibility = M.decide
 
+function M.sample_repeat_timeout_ms(options)
+  return RepeatResolver.new(options):sample_repeat_timeout_ms()
+end
+
 setmetatable(M, {
   __call = function(_, options)
     return RepeatResolver.new(options)
diff --git a/tests/run.lua b/tests/run.lua
index b010908..a2bf7e1 100644
--- a/tests/run.lua
+++ b/tests/run.lua
@@ -3843,6 +3843,23 @@ test("Primary eligibility repeats at a matching numeric landing", function()
   )
 end)
 
+test("Repeated primary timeout is sampled from live policy", function()
+  fresh_sequence_state()
+  local host = MemoryHost.new({
+    configuration = { repeat_timeout_ms = 75 },
+  })
+  local resolver = repeat_resolver.new({
+    policy = policy.new(host),
+  })
+
+  same(75, resolver:sample_repeat_timeout_ms())
+  host:set_configuration("repeat_timeout_ms", 125)
+  same(125, resolver:sample_repeat_timeout_ms())
+  fails(function()
+    repeat_resolver.new():sample_repeat_timeout_ms()
+  end, "requires a policy")
+end)
+
 for _, item in ipairs(tests) do
   local ok, failure = xpcall(item.body, debug.traceback)
   if not ok then