fix: restore testing framework to actually work (#2070)

after refactor to some new asynchronous items for finders,
the tests stopped actually doing anything.

now they do things again.

4 files changed, 270 insertions, 2 deletions

diff --git a/lua/telescope/builtin/__files.lua b/lua/telescope/builtin/__files.lua
index ce5527d..33b1c50 100644
--- a/lua/telescope/builtin/__files.lua
+++ b/lua/telescope/builtin/__files.lua
@@ -180,12 +180,12 @@ files.find_files = function(opts)
         return opts.find_command(opts)
       end
       return opts.find_command
+    elseif 1 == vim.fn.executable "rg" then
+      return { "rg", "--files" }
     elseif 1 == vim.fn.executable "fd" then
       return { "fd", "--type", "f" }
     elseif 1 == vim.fn.executable "fdfind" then
       return { "fdfind", "--type", "f" }
-    elseif 1 == vim.fn.executable "rg" then
-      return { "rg", "--files" }
     elseif 1 == vim.fn.executable "find" and vim.fn.has "win32" == 0 then
       return { "find", ".", "-type", "f" }
     elseif 1 == vim.fn.executable "where" then
diff --git a/lua/telescope/pickers/_test_helpers.lua b/lua/telescope/testharness/helpers.lua
index 5296c45..5296c45 100644
--- a/lua/telescope/pickers/_test_helpers.lua
+++ b/lua/telescope/testharness/helpers.lua
diff --git a/lua/telescope/testharness/init.lua b/lua/telescope/testharness/init.lua
new file mode 100644
index 0000000..9a8e707
--- /dev/null
+++ b/lua/telescope/testharness/init.lua
@@ -0,0 +1,112 @@
+local assert = require "luassert"
+
+local Path = require "plenary.path"
+
+local tester = {}
+tester.debug = false
+
+local get_results_from_contents = function(content)
+  local nvim = vim.fn.jobstart(
+    { "nvim", "--noplugin", "-u", "scripts/minimal_init.vim", "--headless", "--embed" },
+    { rpc = true }
+  )
+
+  local result = vim.fn.rpcrequest(nvim, "nvim_exec_lua", content, {})
+  assert.are.same(true, result[1], vim.inspect(result))
+
+  local count = 0
+  while
+    vim.fn.rpcrequest(nvim, "nvim_exec_lua", "return require('telescope.testharness.runner').state.done", {}) ~= true
+  do
+    count = count + 1
+    vim.wait(100)
+
+    -- TODO: Could maybe wait longer, but it's annoying to wait if the test is going to timeout.
+    if count > 100 then
+      break
+    end
+  end
+
+  local state = vim.fn.rpcrequest(nvim, "nvim_exec_lua", "return require('telescope.testharness.runner').state", {})
+  vim.fn.jobstop(nvim)
+
+  assert.are.same(true, state.done, vim.inspect(state))
+
+  local result_table = {}
+  for _, v in ipairs(state.results) do
+    table.insert(result_table, v)
+  end
+
+  return result_table, state
+end
+
+local check_results = function(results, state)
+  assert(state, "Must pass state")
+
+  for _, v in ipairs(results) do
+    local assertion
+    if not v._type or v._type == "are" or v._type == "_default" then
+      assertion = assert.are.same
+    else
+      assertion = assert.are_not.same
+    end
+
+    -- TODO: I think it would be nice to be able to see the state,
+    -- but it clutters up the test output so much here.
+    --
+    -- So we would have to consider how to do that I think.
+    assertion(v.expected, v.actual, string.format("Test Case: %s // %s", v.location, v.case))
+  end
+end
+
+tester.run_string = function(contents)
+  contents = [[
+    return (function()
+      local tester = require('telescope.testharness')
+      local runner = require('telescope.testharness.runner')
+      local helper = require('telescope.testharness.helpers')
+      helper.make_globals()
+      local ok, msg = pcall(function()
+        runner.log("Loading Test")
+        ]] .. contents .. [[
+      end)
+      return {ok, msg or runner.state}
+    end)()
+  ]]
+
+  check_results(get_results_from_contents(contents))
+end
+
+tester.run_file = function(filename)
+  local file = "./lua/tests/pickers/" .. filename .. ".lua"
+  local path = Path:new(file)
+
+  if not path:exists() then
+    assert.are.same("<An existing file>", file)
+  end
+
+  local contents = string.format(
+    [[
+    return (function()
+      local runner = require('telescope.testharness.runner')
+      local helper = require('telescope.testharness.helpers')
+      helper.make_globals()
+      local ok, msg = pcall(function()
+        runner.log("Loading Test")
+        return loadfile("%s")()
+      end)
+      return {ok, msg or runner.state}
+    end)()
+  ]],
+    path:absolute()
+  )
+
+  check_results(get_results_from_contents(contents))
+end
+
+tester.not_ = function(val)
+  val._type = "are_not"
+  return val
+end
+
+return tester
diff --git a/lua/telescope/testharness/runner.lua b/lua/telescope/testharness/runner.lua
new file mode 100644
index 0000000..af1bf30
--- /dev/null
+++ b/lua/telescope/testharness/runner.lua
@@ -0,0 +1,156 @@
+local builtin = require "telescope.builtin"
+
+local DELAY = vim.g.telescope_test_delay or 50
+local runner = {}
+
+-- State is test variable
+runner.state = {
+  done = false,
+  results = {},
+  msgs = {},
+}
+
+local writer = function(val)
+  table.insert(runner.state.results, val)
+end
+
+local invalid_test_case = function(k)
+  error { case = k, expected = "<a valid key>", actual = k }
+end
+
+local _VALID_KEYS = {
+  post_typed = true,
+  post_close = true,
+}
+
+local replace_terms = function(input)
+  return vim.api.nvim_replace_termcodes(input, true, false, true)
+end
+
+runner.nvim_feed = function(text, feed_opts)
+  feed_opts = feed_opts or "m"
+
+  vim.api.nvim_feedkeys(text, feed_opts, true)
+end
+
+local end_test_cases = function()
+  runner.state.done = true
+end
+
+local execute_test_case = function(location, key, spec)
+  local ok, actual = pcall(spec[2])
+
+  if not ok then
+    writer {
+      location = "Error: " .. location,
+      case = key,
+      expected = "To succeed and return: " .. tostring(spec[1]),
+      actual = actual,
+
+      _type = spec._type,
+    }
+
+    end_test_cases()
+  else
+    writer {
+      location = location,
+      case = key,
+      expected = spec[1],
+      actual = actual,
+
+      _type = spec._type,
+    }
+  end
+
+  return ok
+end
+
+runner.log = function(msg)
+  table.insert(runner.state.msgs, msg)
+end
+
+runner.picker = function(picker_name, input, test_cases, opts)
+  opts = opts or {}
+
+  for k, _ in pairs(test_cases) do
+    if not _VALID_KEYS[k] then
+      return invalid_test_case(k)
+    end
+  end
+
+  opts.on_complete = {
+    runner.create_on_complete(input, test_cases),
+  }
+
+  opts._on_error = function(self, msg)
+    runner.state.done = true
+    writer {
+      location = "Error while running on complete",
+      expected = "To Work",
+      actual = msg,
+    }
+  end
+
+  runner.log "Starting picker"
+  builtin[picker_name](opts)
+  runner.log "Called picker"
+end
+
+runner.create_on_complete = function(input, test_cases)
+  input = replace_terms(input)
+
+  local actions = {}
+  for i = 1, #input do
+    local char = input:sub(i, i)
+    table.insert(actions, {
+      cb = function()
+        runner.log("Inserting char: " .. char)
+        runner.nvim_feed(char, "")
+      end,
+      char = char,
+    })
+  end
+
+  return function()
+    local action
+
+    repeat
+      action = table.remove(actions, 1)
+      if action then
+        action.cb()
+      end
+    until not action or string.match(action.char, "%g")
+
+    if #actions > 0 then
+      return
+    end
+
+    vim.defer_fn(function()
+      if test_cases.post_typed then
+        for k, v in ipairs(test_cases.post_typed) do
+          if not execute_test_case("post_typed", k, v) then
+            return
+          end
+        end
+      end
+
+      vim.defer_fn(function()
+        runner.nvim_feed(replace_terms "<CR>", "")
+
+        vim.defer_fn(function()
+          if test_cases.post_close then
+            for k, v in ipairs(test_cases.post_close) do
+              if not execute_test_case("post_close", k, v) then
+                return
+              end
+            end
+          end
+
+          vim.defer_fn(end_test_cases, DELAY)
+        end, DELAY)
+      end, DELAY)
+    end, DELAY)
+  end
+end
+
+return runner