tests: fix system_spec when run with clipboard manager (#10956)

* tests: move os_kill to functional helpers

* tests: fix system_spec when run with clipboard manager

Replaces "xclip" with a dedicated helper program.

Fixes: https://github.com/neovim/neovim/issues/4900#issuecomment-501866842

CMakeLists.txt

@@ -560,7 +560,7 @@ if(BUSTED_PRG)
   endif()
 
   set(UNITTEST_PREREQS nvim-test unittest-headers)
-  set(FUNCTIONALTEST_PREREQS nvim printargs-test shell-test ${GENERATED_HELP_TAGS})
+  set(FUNCTIONALTEST_PREREQS nvim printargs-test shell-test streams-test ${GENERATED_HELP_TAGS})
   if(NOT WIN32)
     list(APPEND FUNCTIONALTEST_PREREQS tty-test)
   endif()

test/functional/core/job_spec.lua

@@ -7,6 +7,7 @@ local clear, eq, eval, exc_exec, feed_command, feed, insert, neq, next_msg, nvim
   helpers.write_file, helpers.mkdir, helpers.rmdir
 local command = helpers.command
 local funcs = helpers.funcs
+local os_kill = helpers.os_kill
 local retry = helpers.retry
 local meths = helpers.meths
 local NIL = helpers.NIL
@@ -20,13 +21,6 @@ local expect_msg_seq = helpers.expect_msg_seq
 local pcall_err = helpers.pcall_err
 local Screen = require('test.functional.ui.screen')
 
--- Kill process with given pid
-local function os_kill(pid)
-  return os.execute((iswin()
-    and 'taskkill /f /t /pid '..pid..' > nul'
-    or  'kill -9 '..pid..' > /dev/null'))
-end
-
 describe('jobs', function()
   local channel
 

test/functional/eval/system_spec.lua

@@ -7,6 +7,7 @@ local eq, call, clear, eval, feed_command, feed, nvim =
 local command = helpers.command
 local exc_exec = helpers.exc_exec
 local iswin = helpers.iswin
+local os_kill = helpers.os_kill
 
 local Screen = require('test.functional.ui.screen')
 
@@ -23,14 +24,6 @@ local function delete_file(name)
   end
 end
 
--- Some tests require the xclip program and a x server.
-local xclip = nil
-do
-  if os.getenv('DISPLAY') then
-    xclip = (os.execute('command -v xclip > /dev/null 2>&1') == 0)
-  end
-end
-
 describe('system()', function()
   before_each(clear)
 
@@ -378,15 +371,10 @@ describe('system()', function()
     end)
   end)
 
-  describe("with a program that doesn't close stdout", function()
-    if not xclip then
-      pending('missing `xclip`', function() end)
-    else
-      it('will exit properly after passing input', function()
-        eq('', eval([[system('xclip -i -loops 1 -selection clipboard', 'clip-data')]]))
-        eq('clip-data', eval([[system('xclip -o -selection clipboard')]]))
-      end)
-    end
+  it("with a program that doesn't close stdout will exit properly after passing input", function()
+    local out = eval(string.format("system('%s', 'clip-data')", nvim_dir..'/streams-test'))
+    assert(out:sub(0, 5) == 'pid: ', out)
+    os_kill(out:match("%d+"))
   end)
 end)
 
@@ -562,16 +550,9 @@ describe('systemlist()', function()
     end)
   end)
 
-  describe("with a program that doesn't close stdout", function()
-    if not xclip then
-      pending('missing `xclip`', function() end)
-    else
-      it('will exit properly after passing input', function()
-        eq({}, eval(
-          "systemlist('xclip -i -loops 1 -selection clipboard', ['clip', 'data'])"))
-        eq({'clip', 'data'}, eval(
-          "systemlist('xclip -o -selection clipboard')"))
-      end)
-    end
+  it("with a program that doesn't close stdout will exit properly after passing input", function()
+    local out = eval(string.format("systemlist('%s', 'clip-data')", nvim_dir..'/streams-test'))
+    assert(out[1]:sub(0, 5) == 'pid: ', out)
+    os_kill(out[1]:match("%d+"))
   end)
 end)

test/functional/fixtures/CMakeLists.txt

@@ -7,3 +7,6 @@ add_executable(printenv-test printenv-test.c)
 if(WIN32)
   set_target_properties(printenv-test PROPERTIES LINK_FLAGS -municode)
 endif()
+
+add_executable(streams-test streams-test.c)
+target_link_libraries(streams-test ${LIBUV_LIBRARIES})

test/functional/fixtures/streams-test.c

@@ -0,0 +1,33 @@
+/// Helper program to exit and keep stdout open (like "xclip -i -loops 1").
+#include <stdio.h>
+
+#include <uv.h>
+
+uv_loop_t *loop;
+uv_process_t child_req;
+uv_process_options_t options;
+
+int main(int argc, char **argv)
+{
+  loop = uv_default_loop();
+
+  char * args[3];
+  args[0] = "sleep";
+  args[1] = "10";
+  args[2] = NULL;
+
+  options.exit_cb = NULL;
+  options.file = "sleep";
+  options.args = args;
+  options.flags = UV_PROCESS_DETACHED;
+
+  int r;
+  if ((r = uv_spawn(loop, &child_req, &options))) {
+    fprintf(stderr, "%s\n", uv_strerror(r));
+    return 1;
+  }
+  fprintf(stderr, "pid: %d\n", child_req.pid);
+  uv_unref((uv_handle_t *)&child_req);
+
+  return uv_run(loop, UV_RUN_DEFAULT);
+}

test/functional/helpers.lua

@@ -796,6 +796,13 @@ function module.add_builddir_to_rtp()
   module.command(string.format([[set rtp+=%s/runtime]], module.test_build_dir))
 end
 
+-- Kill process with given pid
+function module.os_kill(pid)
+  return os.execute((iswin()
+    and 'taskkill /f /t /pid '..pid..' > nul'
+    or  'kill -9 '..pid..' > /dev/null'))
+end
+
 module = global_helpers.tbl_extend('error', module, global_helpers)
 
 return function(after_each)