feat(files): add methods for tag addition/removal/toggling (#894)

Co-authored-by: troiganto <troiganto@proton.me>

Author: troiganto

lua/orgmode/files/headline.lua

@@ -288,6 +288,49 @@ function Headline:set_tags(tags)
   vim.api.nvim_buf_set_text(bufnr, pred_end_row, pred_end_col, pred_end_row, end_col, { text })
 end
 
+---@param tag string
+---@return boolean newly_added
+function Headline:add_tag(tag)
+  local current_tags = self:get_own_tags()
+  local present = vim.tbl_contains(current_tags, tag)
+  if not present then
+    table.insert(current_tags, tag)
+  end
+  self:set_tags(utils.tags_to_string(current_tags))
+  return not present
+end
+
+---@param tag string
+---@return boolean newly_removed
+function Headline:remove_tag(tag)
+  local current_tags = self:get_own_tags()
+  ---@type string[]
+  local new_tags = vim.tbl_filter(function(i)
+    return i ~= tag
+  end, current_tags)
+  local present = #new_tags ~= #current_tags
+  if present then
+    self:set_tags(utils.tags_to_string(new_tags))
+  end
+  return present
+end
+
+---@param tag string
+---@return boolean newly_added
+function Headline:toggle_tag(tag)
+  local current_tags = self:get_own_tags()
+  local present = vim.tbl_contains(current_tags, tag)
+  if present then
+    current_tags = vim.tbl_filter(function(i)
+      return i ~= tag
+    end, current_tags)
+  else
+    table.insert(current_tags, tag)
+  end
+  self:set_tags(utils.tags_to_string(current_tags))
+  return not present
+end
+
 function Headline:align_tags()
   local own_tags, node = self:get_own_tags()
   if node then

lua/orgmode/org/mappings.lua

@@ -71,19 +71,10 @@ function OrgMappings:set_tags(tags)
     end)
 end
 
+---@return nil
 function OrgMappings:toggle_archive_tag()
   local headline = self.files:get_closest_headline()
-  local current_tags = headline:get_own_tags()
-
-  if vim.tbl_contains(current_tags, 'ARCHIVE') then
-    current_tags = vim.tbl_filter(function(tag)
-      return tag ~= 'ARCHIVE'
-    end, current_tags)
-  else
-    table.insert(current_tags, 'ARCHIVE')
-  end
-
-  return headline:set_tags(utils.tags_to_string(current_tags))
+  headline:toggle_tag('ARCHIVE')
 end
 
 function OrgMappings:cycle()

tests/plenary/files/headline_spec.lua

@@ -152,4 +152,139 @@ describe('Headline', function()
       assert_range(second_headline_dates[3], { 5, 3, 5, 18 })
     end)
   end)
+
+  describe('tags', function()
+    ---@type OrgFile
+    local file
+    local orig_tags_column
+
+    before_each(function()
+      -- Put tags flush to headlines for shorter tests.
+      if not orig_tags_column then
+        orig_tags_column = config.org_tags_column
+      end
+      config:extend({ org_tags_column = 0 })
+      -- Reinitialize test file to same state.
+      if not file then
+        file = helpers.load_file(vim.fn.tempname() .. '.org')
+      end
+      local bufnr = file:get_valid_bufnr()
+      vim.api.nvim_buf_set_lines(bufnr, 0, -1, true, {
+        '* Headline 1',
+        '* Headline 2 :other:',
+        '* Headline 3 :other:more:ARCHIVE:',
+      })
+      file:reload_sync()
+    end)
+
+    after_each(function()
+      config:extend({ org_tags_column = orig_tags_column })
+    end)
+
+    describe('toggling', function()
+      it('adds a tag where there is none', function()
+        file:get_headlines()[1]:toggle_tag('ARCHIVE')
+        local expected = {
+          '* Headline 1 :ARCHIVE:',
+          '* Headline 2 :other:',
+          '* Headline 3 :other:more:ARCHIVE:',
+        }
+        assert.are.same(expected, file:reload_sync().lines)
+      end)
+
+      it('adds a tag if another already exists', function()
+        file:get_headlines()[2]:toggle_tag('ARCHIVE')
+        local expected = {
+          '* Headline 1',
+          '* Headline 2 :other:ARCHIVE:',
+          '* Headline 3 :other:more:ARCHIVE:',
+        }
+        assert.are.same(expected, file:reload_sync().lines)
+      end)
+
+      it('removes an existing tag', function()
+        file:get_headlines()[2]:toggle_tag('other')
+        local expected = {
+          '* Headline 1',
+          '* Headline 2',
+          '* Headline 3 :other:more:ARCHIVE:',
+        }
+        assert.are.same(expected, file:reload_sync().lines)
+      end)
+
+      it('keeps other tags when removing one', function()
+        file:get_headlines()[3]:toggle_tag('more')
+        local expected = {
+          '* Headline 1',
+          '* Headline 2 :other:',
+          '* Headline 3 :other:ARCHIVE:',
+        }
+        assert.are.same(expected, file:reload_sync().lines)
+      end)
+    end)
+
+    describe('addition', function()
+      it('adds a tag where there is none', function()
+        file:get_headlines()[1]:add_tag('ARCHIVE')
+        local expected = {
+          '* Headline 1 :ARCHIVE:',
+          '* Headline 2 :other:',
+          '* Headline 3 :other:more:ARCHIVE:',
+        }
+        assert.are.same(expected, file:reload_sync().lines)
+      end)
+
+      it('adds a tag if another already exists', function()
+        file:get_headlines()[2]:add_tag('ARCHIVE')
+        local expected = {
+          '* Headline 1',
+          '* Headline 2 :other:ARCHIVE:',
+          '* Headline 3 :other:more:ARCHIVE:',
+        }
+        assert.are.same(expected, file:reload_sync().lines)
+      end)
+
+      it('does not add the same tag twice', function()
+        file:get_headlines()[2]:add_tag('other')
+        local expected = {
+          '* Headline 1',
+          '* Headline 2 :other:',
+          '* Headline 3 :other:more:ARCHIVE:',
+        }
+        assert.are.same(expected, file:reload_sync().lines)
+      end)
+    end)
+
+    describe('removal', function()
+      it('removes an existing tag', function()
+        file:get_headlines()[2]:remove_tag('other')
+        local expected = {
+          '* Headline 1',
+          '* Headline 2',
+          '* Headline 3 :other:more:ARCHIVE:',
+        }
+        assert.are.same(expected, file:reload_sync().lines)
+      end)
+
+      it('keeps other tags when removing one', function()
+        file:get_headlines()[3]:remove_tag('more')
+        local expected = {
+          '* Headline 1',
+          '* Headline 2 :other:',
+          '* Headline 3 :other:ARCHIVE:',
+        }
+        assert.are.same(expected, file:reload_sync().lines)
+      end)
+
+      it('does nothing when removing a non-existent tag', function()
+        file:get_headlines()[1]:remove_tag('other')
+        local expected = {
+          '* Headline 1',
+          '* Headline 2 :other:',
+          '* Headline 3 :other:more:ARCHIVE:',
+        }
+        assert.are.same(expected, file:reload_sync().lines)
+      end)
+    end)
+  end)
 end)