1 files changed, 205 insertions, 0 deletions
diff --git a/test/harness.lua b/test/harness.lua
new file mode 100644
index 0000000..b6b3a65
--- /dev/null
+++ b/test/harness.lua
@@ -0,0 +1,205 @@
+--- Assertions, the test registry and control of the fake server.
+--
+-- No rock beyond the ones the library already needs: registering a test is
+-- `test(name, fn)`, a failure is an `error()` out of an assertion, and the
+-- runner exits non-zero if any of them fires.
+
+local http = require("socket.http")
+local ltn12 = require("ltn12")
+local socket = require("socket")
+local json = require("dkjson")
+
+local M = {}
+
+M.tests = {}
+
+--- Register a test. Order of registration is order of execution.
+function M.test(name, fn)
+  M.tests[#M.tests + 1] = { name = name, fn = fn }
+end
+
+local function fail(message, level)
+  error(message, (level or 2) + 1)
+end
+
+local function show(value)
+  if type(value) == "string" then
+    return string.format("%q", value)
+  end
+  return tostring(value)
+end
+
+function M.ok(value, message)
+  if not value then
+    fail(message or ("expected a truthy value, got " .. show(value)))
+  end
+end
+
+function M.falsy(value, message)
+  if value then
+    fail(message or ("expected a falsy value, got " .. show(value)))
+  end
+end
+
+function M.equal(got, want, message)
+  if got ~= want then
+    fail(
+      (message and (message .. ": ") or "")
+        .. "expected "
+        .. show(want)
+        .. ", got "
+        .. show(got)
+    )
+  end
+end
+
+function M.near(got, want, message)
+  if type(got) ~= "number" or math.abs(got - want) > 1e-6 then
+    fail((message and (message .. ": ") or "") .. "expected ~" .. tostring(want) .. ", got " .. show(got))
+  end
+end
+
+function M.is_nil(value, message)
+  if value ~= nil then
+    fail(message or ("expected nil, got " .. show(value)))
+  end
+end
+
+function M.is_false(value, message)
+  if value ~= false then
+    fail(message or ("expected false, got " .. show(value)))
+  end
+end
+
+--- Assert a call failed with a given error kind, and return the error.
+function M.error_kind(value, err, kind)
+  if value ~= nil then
+    fail("expected a failure, got " .. show(value))
+  end
+  if type(err) ~= "table" or err.kind == nil then
+    fail("expected a cepis error, got " .. show(err))
+  end
+  if err.kind ~= kind then
+    fail("expected kind " .. show(kind) .. ", got " .. show(err.kind) .. " (" .. tostring(err.message) .. ")")
+  end
+  return err
+end
+
+--- Assert a call raised through `error()`, for programmer mistakes.
+function M.raises(fn, ...)
+  local ok = pcall(fn, ...)
+  if ok then
+    fail("expected error() to be raised")
+  end
+end
+
+local function request(url, body)
+  local chunks = {}
+  local headers = nil
+  local source = nil
+  if body then
+    source = ltn12.source.string(body)
+    headers = {
+      ["content-length"] = tostring(#body),
+      ["content-type"] = "application/json",
+    }
+  end
+  local ok, code = http.request({
+    url = url,
+    method = body and "POST" or "GET",
+    source = source,
+    headers = headers,
+    sink = ltn12.sink.table(chunks),
+  })
+  if not ok then
+    error("control request to " .. url .. " failed: " .. tostring(code))
+  end
+  return table.concat(chunks)
+end
+
+local Server = {}
+Server.__index = Server
+
+--- Replace the routes and clear the call log.
+function Server:program(routes)
+  request(self.url .. "/__program", json.encode(routes))
+end
+
+--- Every request target the server has seen since the last `program`.
+function Server:calls()
+  return json.decode(request(self.url .. "/__calls")) or {}
+end
+
+--- How many of them began with `prefix`.
+function Server:count(prefix)
+  local total = 0
+  for _, target in ipairs(self:calls()) do
+    if target:sub(1, #prefix) == prefix then
+      total = total + 1
+    end
+  end
+  return total
+end
+
+function Server:stop()
+  pcall(request, self.url .. "/__stop")
+end
+
+--- Spawn the fake server and wait for it to report its port.
+function M.start_server()
+  local directory = (arg[0] or "test/run.lua"):match("^(.*)[/\\]") or "."
+  local portfile = os.tmpname()
+  os.remove(portfile)
+
+  local interpreter = arg[-1] or "lua"
+  os.execute(
+    string.format(
+      "%s %s/server.lua %s >/dev/null 2>&1 &",
+      interpreter,
+      directory,
+      portfile
+    )
+  )
+
+  local port
+  local deadline = socket.gettime() + 10
+  while socket.gettime() < deadline do
+    local handle = io.open(portfile, "r")
+    if handle then
+      local content = handle:read("*a")
+      handle:close()
+      port = tonumber(content)
+      if port then
+        break
+      end
+    end
+    socket.sleep(0.02)
+  end
+
+  os.remove(portfile)
+  if not port then
+    error("the fake server did not start")
+  end
+
+  return setmetatable({ url = "http://127.0.0.1:" .. port, port = port }, Server)
+end
+
+--- Run every registered test, printing one line each.
+function M.run()
+  local failures = 0
+  for _, entry in ipairs(M.tests) do
+    local ok, err = pcall(entry.fn)
+    if ok then
+      print("ok   - " .. entry.name)
+    else
+      failures = failures + 1
+      print("FAIL - " .. entry.name)
+      print("       " .. tostring(err))
+    end
+  end
+
+  print(string.format("\n%d test(s), %d failure(s)", #M.tests, failures))
+  return failures
+end
+
+return M