1 files changed, 57 insertions, 0 deletions
diff --git a/test/functional/core/log_spec.lua b/test/functional/core/log_spec.lua
new file mode 100644
index 0000000000..3b1ccd9559
--- /dev/null
+++ b/test/functional/core/log_spec.lua
@@ -0,0 +1,57 @@
+local helpers = require('test.functional.helpers')(after_each)
+local assert_log = helpers.assert_log
+local clear = helpers.clear
+local command = helpers.command
+local eq = helpers.eq
+local exec_lua = helpers.exec_lua
+local expect_exit = helpers.expect_exit
+local request = helpers.request
+local retry = helpers.retry
+
+describe('log', function()
+  local testlog = 'Xtest_logging'
+
+  after_each(function()
+    expect_exit(command, 'qa!')
+    os.remove(testlog)
+  end)
+
+  it('skipped before log_init', function()
+    -- This test is for _visibility_: adjust as needed, after checking for regression.
+    --
+    -- During startup some components may try to log before logging is setup.
+    -- That should be uncommon (ideally never)--and if there are MANY such
+    -- calls, that needs investigation.
+    clear()
+    eq(0, request('nvim__stats').log_skip)
+    clear{env={CDPATH='~doesnotexist'}}
+    assert(request('nvim__stats').log_skip <= 13)
+  end)
+
+  it('messages are formatted with name or test id', function()
+    -- Examples:
+    --    ERR 2022-05-29T12:30:03.800 T2         log_init:110: test log message
+    --    ERR 2022-05-29T12:30:03.814 T2/child   log_init:110: test log message
+
+    clear({env={
+      NVIM_LOG_FILE=testlog,
+      -- TODO: remove this after nvim_log #7062 is merged.
+      __NVIM_TEST_LOG='1'
+      }})
+
+    local tid = _G._nvim_test_id
+    retry(nil, 1000, function()
+      assert_log(tid..'%.%d+%.%d +server_init:%d+: test log message', testlog, 100)
+    end)
+
+    exec_lua([[
+      local j1 = vim.fn.jobstart({ vim.v.progpath, '-es', '-V1', '+foochild', '+qa!' }, vim.empty_dict())
+      vim.fn.jobwait({ j1 }, 10000)
+    ]])
+
+    -- Child Nvim spawned by jobstart() appends "/c" to parent name.
+    retry(nil, 1000, function()
+      assert_log('%.%d+%.%d/c +server_init:%d+: test log message', testlog, 100)
+    end)
+  end)
+end)