split lock file functions into separate file to enable testing

5 files changed, 120 insertions, 74 deletions

diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 555786b..ce373b1 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -2,6 +2,7 @@ image: muhq/lua-dev:0.1
 
 stages:
   - check
+  - test
 
 check-luacheck:
   stage: check
@@ -14,3 +15,9 @@ check-format:
   script:
     - luarocks install --server=https://luarocks.org/dev luaformatter
     - make check-format
+
+test:
+  stage: test
+  script:
+    - luarocks install lunatest
+    - make test
diff --git a/Makefile b/Makefile
index 816596e..855b34b 100644
--- a/Makefile
+++ b/Makefile
@@ -1,6 +1,7 @@
 .PHONY: check format check-luacheck check-format
 
 LUA_FILES := $(shell find -name "*.lua")
+TEST_FILES := $(shell find -name "*_test.lua")
 
 check: check-luacheck check-format
 
@@ -12,3 +13,6 @@ check-format:
 
 format:
 	lua-format -i $(LUA_FILES)
+
+test:
+	set -e; for tf in $(TEST_FILES); do "$$tf"; done
diff --git a/init.lua b/init.lua
index 25735bb..5c85818 100644
--- a/init.lua
+++ b/init.lua
@@ -12,51 +12,23 @@
 -- You should have received a copy of the GNU General Public License along with
 -- vis-lockfiles found in the LICENSE file.
 -- If not, see <https://www.gnu.org/licenses/>.
+local source_str = debug.getinfo(1, 'S').source:sub(2)
+local script_path = source_str:match('(.*/)')
+
+local lockfiles = dofile(script_path .. 'lockfiles.lua')
+
 local M = {}
 M.directory = '${XDG_STATE_HOME:-${HOME}/.local/state}/vis/locks'
 M.directory_expanded = nil
 
--- Helper to execute a command and capture its output
-local function capture_cmd(cmd)
-  local p = assert(io.popen(cmd, 'r'))
-  local s = assert(p:read('*a'))
-  local success, _, status = p:close()
-  if not success then
-    local err = cmd .. ' failed with exit code: ' .. status
-    vis:info('vis-lockfiles: ' .. err)
-  end
-  return s
-end
-
 local function get_lock_dir()
   if M.directory_expanded ~= M.directory then
-    M.directory = capture_cmd('printf %s "' .. M.directory .. '"')
+    M.directory = lockfiles.capture_cmd('printf %s "' .. M.directory .. '"')
     M.directory_expanded = M.directory
   end
   return M.directory
 end
 
-local function lock_file_path(path)
-  -- escape '%' first
-  local filename = path:gsub('%%', '%%25'):gsub('/', '%%2F')
-  return get_lock_dir() .. '/' .. filename .. '.lock'
-end
-
--- determine vis' pid
-local vis_pid
-do
-  local vis_proc_file = io.open('/proc/self/stat', 'r')
-  if vis_proc_file then
-    vis_pid = vis_proc_file:read('*n')
-    vis_proc_file:close()
-
-  else -- fallback if /proc/self/stat is not available
-    local out = capture_cmd('sh -c "echo $PPID"')
-    vis_pid = tonumber(out)
-  end
-end
-assert(vis_pid)
-
 -- get a user confirmation
 -- return true if user selected yes, false otherwise
 local function confirm(path)
@@ -82,49 +54,15 @@ local function confirm(path)
 end
 
 local created_locks = {}
-local function create_lock_file(lfile_path)
-  local lock_file = io.open(lfile_path)
-  if lock_file then
-    lock_file:close()
-    return false
-  end
-
-  -- create the lock file with our pid
-  if not io.open(lfile_path, 'w') then
-    assert(os.execute('mkdir -p "' .. get_lock_dir() .. '"'))
-  end
-  lock_file = assert(io.open(lfile_path, 'w'))
-  lock_file:write(vis_pid)
-  lock_file:close()
-
-  -- detect a possible race
-  lock_file = assert(io.open(lfile_path))
-  local lock_pid = lock_file:read('*n')
-  lock_file:close()
-  local locked = tonumber(lock_pid) == vis_pid
-
-  -- remember we created the lock file
-  if locked then
-    created_locks[lfile_path] = true
-  end
-
-  return locked
-end
-
-local function delete_lock_file(lfile_path)
-  local success, err = os.remove(lfile_path)
-  if not success then
-    vis:info('vis-lockfiles: ' .. err)
-  end
-  created_locks[lfile_path] = nil
-end
 
 vis.events.subscribe(vis.events.FILE_OPEN, function(file)
   if not file.path then
     return
   end
-  local lfile_path = lock_file_path(file.path)
-  if not create_lock_file(lfile_path) and not confirm(lfile_path) then
+  local lfile_path = lockfiles.lock_file_path(get_lock_dir(), file.path)
+  if lockfiles.create_lock_file(get_lock_dir(), lfile_path) then
+    created_locks[lfile_path] = true
+  elseif not confirm(lfile_path) then
     os.exit(1)
   end
 end)
@@ -133,9 +71,10 @@ vis.events.subscribe(vis.events.FILE_CLOSE, function(file)
   if not file.path then
     return
   end
-  local lfile_path = lock_file_path(file.path)
+  local lfile_path = lockfiles.lock_file_path(get_lock_dir(), file.path)
   if created_locks[lfile_path] then
-    delete_lock_file(lfile_path)
+    lockfiles.delete_lock_file(lfile_path)
+    created_locks[lfile_path] = nil
   end
 end)
 
diff --git a/lockfiles.lua b/lockfiles.lua
new file mode 100644
index 0000000..9e120bd
--- /dev/null
+++ b/lockfiles.lua
@@ -0,0 +1,84 @@
+-- Copyright (c) 2024 Florian Fischer. All rights reserved.
+--
+-- vis-lockfiles is free software: you can redistribute it and/or modify it under
+-- the terms of the GNU General Public License as published by the Free Software
+-- Foundation, either version 3 of the License, or (at your option) any later
+-- version.
+--
+-- vis-lockfiles is distributed in the hope that it will be useful, but WITHOUT
+-- ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+-- FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
+--
+-- You should have received a copy of the GNU General Public License along with
+-- vis-lockfiles found in the LICENSE file.
+-- If not, see <https://www.gnu.org/licenses/>.
+-- Helper to execute a command and capture its output
+local function capture_cmd(cmd)
+  local p = assert(io.popen(cmd, 'r'))
+  local s = assert(p:read('*a'))
+  local success, _, status = p:close()
+  if not success then
+    local err = cmd .. ' failed with exit code: ' .. status
+    vis:info('vis-lockfiles: ' .. err)
+  end
+  return s
+end
+
+local function lock_file_path(lock_dir, path)
+  -- escape '%' first
+  local filename = path:gsub('%%', '%%25'):gsub('/', '%%2F')
+  return lock_dir .. '/' .. filename .. '.lock'
+end
+
+-- determine vis' pid
+local vis_pid
+do
+  local vis_proc_file = io.open('/proc/self/stat', 'r')
+  if vis_proc_file then
+    vis_pid = vis_proc_file:read('*n')
+    vis_proc_file:close()
+
+  else -- fallback if /proc/self/stat is not available
+    local out = capture_cmd('sh -c "echo $PPID"')
+    vis_pid = tonumber(out)
+  end
+end
+assert(vis_pid)
+
+local function create_lock_file(lock_dir, lfile_path)
+  local lock_file = io.open(lfile_path)
+  if lock_file then
+    lock_file:close()
+    return false
+  end
+
+  -- create the lock file with our pid
+  if not io.open(lfile_path, 'w') then
+    assert(os.execute('mkdir -p "' .. lock_dir .. '"'))
+  end
+  lock_file = assert(io.open(lfile_path, 'w'))
+  lock_file:write(vis_pid)
+  lock_file:close()
+
+  -- detect a possible race
+  lock_file = assert(io.open(lfile_path))
+  local lock_pid = lock_file:read('*n')
+  lock_file:close()
+  local locked = tonumber(lock_pid) == vis_pid
+
+  return locked
+end
+
+local function delete_lock_file(lfile_path)
+  local success, err = os.remove(lfile_path)
+  if not success then
+    vis:info('vis-lockfiles: ' .. err)
+  end
+end
+
+return {
+  capture_cmd = capture_cmd,
+  lock_file_path = lock_file_path,
+  delete_lock_file = delete_lock_file,
+  create_lock_file = create_lock_file,
+}
diff --git a/lockfiles_test.lua b/lockfiles_test.lua
new file mode 100755
index 0000000..a393f60
--- /dev/null
+++ b/lockfiles_test.lua
@@ -0,0 +1,12 @@
+#!/usr/bin/env lua5.4
+
+local lockfiles = dofile('lockfiles.lua')
+
+local lunatest = require('lunatest')
+function test_percentage_escape() -- luacheck: ignore 111
+  local lock_file_path_with_percent = lockfiles.lock_file_path('.', 'foo%bar')
+  local lock_file_path_with_slash = lockfiles.lock_file_path('.', 'foo/bar')
+  lunatest.assert_not_equal(lock_file_path_with_percent, lock_file_path_with_slash)
+end
+
+lunatest.run()