Add vim/env handler

doc/cmdbuf.nvim.txt

@@ -53,12 +53,13 @@ CmdbufOpenOption                                            *CmdbufOpenOption*
 - {type} (CmdbufHandlerType?) (default = "vim/cmd") |CmdbufHandlerType|
 
 CmdbufHandlerType                                          *CmdbufHandlerType*
-  = "vim/cmd" | "vim/search/forward" | "vim/search/backward" | "vim/input" | "lua/cmd" | "lua/variable/buffer" | "lua/variable/global"
+  = "vim/cmd" | "vim/search/forward" | "vim/search/backward" | "vim/input" | "vim/env" | "lua/cmd" | "lua/variable/buffer" | "lua/variable/global"
 
 - "vim/cmd": |q:| alternative
 - "vim/search/forward": |q/| alternative
 - "vim/search/backward": |q?| alternative
 - "vim/input": show input history
+- "vim/env": environment variable
 - "lua/cmd": |q:| alternative for lua command
 - "lua/variable/buffer": buffer variable and command
 - "lua/variable/global": global variable and command

lua/cmdbuf/handler/vim/env.lua

@@ -0,0 +1,45 @@
+local M = {}
+M.__index = M
+
+function M.new()
+  return setmetatable({}, M)
+end
+
+function M.histories()
+  local names = vim.fn.getcompletion("*", "environment")
+  local key_values = {}
+  for _, name in ipairs(names) do
+    local key_value = ("%s=%s"):format(name, os.getenv(name):gsub("\n", "\\n"))
+    table.insert(key_values, key_value)
+  end
+  return key_values
+end
+
+function M.add_history(_, _) end
+
+local extract_key_value = function(line)
+  local index = line:find("=")
+  if not index then
+    return line
+  end
+
+  local key = line:sub(1, index - 1)
+  local value = line:sub(index + 1)
+  return key, value
+end
+
+function M.delete_histories(_, lines)
+  for _, line in ipairs(lines) do
+    local key, _ = extract_key_value(line)
+    vim.env[key] = nil
+  end
+end
+
+function M.execute(_, line)
+  local key, value = extract_key_value(line)
+  vim.env[key] = value
+end
+
+M.filetype = ""
+
+return M

lua/cmdbuf/init.lua

@@ -12,6 +12,7 @@ local M = {}
 --- | '"vim/search/forward"' # |q/| alternative
 --- | '"vim/search/backward"' # |q?| alternative
 --- | '"vim/input"' # show input history
+--- | '"vim/env"' # environment variable
 --- | '"lua/cmd"' # |q:| alternative for lua command
 --- | '"lua/variable/buffer"' # buffer variable and command
 --- | '"lua/variable/global"' # global variable and command

spec/lua/cmdbuf/handler/vim/env_spec.lua

@@ -0,0 +1,42 @@
+local helper = require("cmdbuf.test.helper")
+local cmdbuf = helper.require("cmdbuf")
+
+describe("vim/env handler", function()
+  before_each(function()
+    vim.env.CMDBUF_TEST = nil
+    helper.before_each()
+  end)
+  after_each(helper.after_each)
+
+  it("can open a buffer", function()
+    local origin = vim.api.nvim_get_current_buf()
+
+    cmdbuf.open({ type = "vim/env" })
+
+    assert.buffer_full_name("cmdbuf://vim/env-buffer")
+    assert.filetype("")
+    assert.no.buffer_number(origin)
+  end)
+
+  it("sets environment variable on execution", function()
+    cmdbuf.open({ type = "vim/env" })
+    helper.set_lines([[CMDBUF_TEST=value]])
+
+    cmdbuf.execute({ quit = true })
+    cmdbuf.open({ type = "vim/env" })
+
+    assert.exists_pattern([[^CMDBUF_TEST=value$]])
+  end)
+
+  it("can unset variable by delete", function()
+    vim.env.CMDBUF_TEST = "delete_target"
+
+    cmdbuf.open({ type = "vim/env" })
+    helper.search("delete_target")
+    cmdbuf.delete()
+    assert.no.exists_pattern("CMDBUF_TEST=delete_target")
+
+    vim.cmd.edit({ bang = true })
+    assert.no.exists_pattern("CMDBUF_TEST=delete_target")
+  end)
+end)