From d071c0e5d0ddd7d9a65d80f883bae6cf62f107ba Mon Sep 17 00:00:00 2001
From: troiganto <troiganto@proton.me>
Date: Wed, 5 Feb 2025 22:56:48 +0100
Subject: [PATCH 1/3] refactor(tests): add minimal test for folding

---
 tests/plenary/org/fold_spec.lua | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)
 create mode 100644 tests/plenary/org/fold_spec.lua

diff --git a/tests/plenary/org/fold_spec.lua b/tests/plenary/org/fold_spec.lua
new file mode 100644
index 000000000..6f28f9e6c
--- /dev/null
+++ b/tests/plenary/org/fold_spec.lua
@@ -0,0 +1,17 @@
+local helpers = require('tests.plenary.helpers')
+
+describe('folding', function()
+  it('works', function()
+    helpers.create_file({
+      '* First',
+      '** Second',
+      '*** Third',
+      '**** Fourth',
+      '***** Fifth',
+      'text',
+    })
+    vim.cmd.normal({ 'GzM', bang = true })
+    local foldlevel = vim.fn.foldlevel(6)
+    assert.are.same(5, foldlevel)
+  end)
+end)

From c944f9c2ef8d8e315e2318ea3ee95602c736633b Mon Sep 17 00:00:00 2001
From: troiganto <troiganto@proton.me>
Date: Wed, 5 Feb 2025 23:31:57 +0100
Subject: [PATCH 2/3] refactor(tests): add tests for `readfile()` and
 `writefile()`

---
 tests/plenary/utils_spec.lua | 87 ++++++++++++++++++++++++++++++++++++
 1 file changed, 87 insertions(+)

diff --git a/tests/plenary/utils_spec.lua b/tests/plenary/utils_spec.lua
index b969eb23b..c87ca60b4 100644
--- a/tests/plenary/utils_spec.lua
+++ b/tests/plenary/utils_spec.lua
@@ -38,4 +38,91 @@ describe('Util', function()
       end)
     end)
   end)
+
+  describe('readfile', function()
+    ---@type OrgFile
+    local file
+    before_each(function()
+      if not file then
+        file = helpers.create_file({
+          'First line',
+          '',
+          '* Headline',
+          'Contents',
+        })
+      end
+    end)
+
+    it('returns lines', function()
+      local contents = utils.readfile(file.filename):wait()
+      assert.are.same(contents, {
+        'First line',
+        '',
+        '* Headline',
+        'Contents',
+      })
+    end)
+
+    it('returns raw contents', function()
+      local contents = utils.readfile(file.filename, { raw = true }):wait()
+      assert.are.equal(contents, 'First line\n\n* Headline\nContents\n')
+    end)
+
+    it('schedules its results for later', function()
+      utils
+        .readfile(file.filename, { schedule = true })
+        :next(function(contents)
+          -- Without `schedule = true`, this line would run inside `fast-api`
+          -- and thus fail.
+          vim.fn.setreg('', contents)
+        end)
+        :wait()
+      local contents = vim.fn.getreg('')
+      assert.are.equal(contents, 'First line\n\n* Headline\nContents\n')
+    end)
+  end)
+
+  describe('writefile', function()
+    ---@type string
+    local filename
+    before_each(function()
+      if not filename then
+        filename = vim.fn.tempname()
+      end
+    end)
+
+    local contents = {
+      'First line',
+      '',
+      '* Headline',
+      'Contents',
+    }
+
+    it('writes bare strings', function()
+      local bytes = utils.writefile(filename, table.concat(contents, '\n')):wait()
+      assert.are.equal(bytes, 31)
+      local reread = vim.fn.readfile(filename)
+      assert.are.same(reread, contents)
+    end)
+
+    it('writes lists of strings by concatenation', function()
+      local bytes = utils.writefile(filename, contents):wait()
+      assert.are.equal(bytes, 28)
+      local reread = vim.fn.readfile(filename)
+      assert.are.same(reread, { 'First line* HeadlineContents' })
+    end)
+
+    it('does not schedule its results', function()
+      local promise = utils.writefile(filename, contents):next(function(bytes)
+        return vim.fn.setreg('', bytes)
+      end)
+      ---@type boolean, string?
+      local ok, err = pcall(promise.wait, promise)
+      assert.is.False(ok)
+      assert(err)
+      local expected = 'E5560: Vimscript function must not be called in a lua loop callback'
+      local msg = err:sub(#err - #expected)
+      assert.are.equal(expected, msg)
+    end)
+  end)
 end)

From 884959201b61e75488ae03d0b72b28411312c95c Mon Sep 17 00:00:00 2001
From: troiganto <troiganto@proton.me>
Date: Sat, 25 Jan 2025 22:56:21 +0100
Subject: [PATCH 3/3] feat(utils): add optional parameter `opts` to
 `writefile()`

---
 lua/orgmode/utils/init.lua   |  6 ++++--
 tests/plenary/utils_spec.lua | 10 ++++++++++
 2 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/lua/orgmode/utils/init.lua b/lua/orgmode/utils/init.lua
index 321444cc4..443f59340 100644
--- a/lua/orgmode/utils/init.lua
+++ b/lua/orgmode/utils/init.lua
@@ -55,10 +55,12 @@ end
 
 ---@param file string
 ---@param data string|string[]
+---@param opts? {excl?: boolean}
 ---@return OrgPromise<integer> bytes
-function utils.writefile(file, data)
+function utils.writefile(file, data, opts)
   return Promise.new(function(resolve, reject)
-    uv.fs_open(file, 'w', 438, function(err1, fd)
+    local flags = opts and opts.excl and 'wx' or 'w'
+    uv.fs_open(file, flags, 438, function(err1, fd)
       if err1 then
         return reject(err1)
       end
diff --git a/tests/plenary/utils_spec.lua b/tests/plenary/utils_spec.lua
index c87ca60b4..0e5afce3f 100644
--- a/tests/plenary/utils_spec.lua
+++ b/tests/plenary/utils_spec.lua
@@ -124,5 +124,15 @@ describe('Util', function()
       local msg = err:sub(#err - #expected)
       assert.are.equal(expected, msg)
     end)
+
+    it('allows no-clobber writes', function()
+      local promise = utils.writefile(filename, contents, { excl = true })
+      ---@type boolean, string?
+      local ok, err = pcall(promise.wait, promise)
+      assert.is.False(ok)
+      assert(err)
+      local expected = 'EEXIST: file already exists: ' .. filename
+      assert.are.equal(expected, err)
+    end)
   end)
 end)