feat(test): testing infrastructure

spec/highlight_spec.lua

@@ -0,0 +1,217 @@
+require('spec.helpers')
+local highlight = require('fugitive-ts.highlight')
+
+describe('highlight', function()
+  describe('highlight_hunk', function()
+    local ns
+
+    before_each(function()
+      ns = vim.api.nvim_create_namespace('fugitive_ts_test')
+    end)
+
+    local function create_buffer(lines)
+      local bufnr = vim.api.nvim_create_buf(false, true)
+      vim.api.nvim_buf_set_lines(bufnr, 0, -1, false, lines)
+      return bufnr
+    end
+
+    local function delete_buffer(bufnr)
+      if vim.api.nvim_buf_is_valid(bufnr) then
+        vim.api.nvim_buf_delete(bufnr, { force = true })
+      end
+    end
+
+    local function get_extmarks(bufnr)
+      return vim.api.nvim_buf_get_extmarks(bufnr, ns, 0, -1, { details = true })
+    end
+
+    it('applies extmarks for lua code', function()
+      local bufnr = create_buffer({
+        '@@ -1,1 +1,2 @@',
+        ' local x = 1',
+        '+local y = 2',
+      })
+
+      local hunk = {
+        filename = 'test.lua',
+        lang = 'lua',
+        start_line = 1,
+        lines = { ' local x = 1', '+local y = 2' },
+      }
+
+      highlight.highlight_hunk(bufnr, ns, hunk, 500, false, false)
+
+      local extmarks = get_extmarks(bufnr)
+      assert.is_true(#extmarks > 0)
+      delete_buffer(bufnr)
+    end)
+
+    it('applies Normal extmarks to clear diff colors', function()
+      local bufnr = create_buffer({
+        '@@ -1,1 +1,2 @@',
+        ' local x = 1',
+        '+local y = 2',
+      })
+
+      local hunk = {
+        filename = 'test.lua',
+        lang = 'lua',
+        start_line = 1,
+        lines = { ' local x = 1', '+local y = 2' },
+      }
+
+      highlight.highlight_hunk(bufnr, ns, hunk, 500, false, false)
+
+      local extmarks = get_extmarks(bufnr)
+      local has_normal = false
+      for _, mark in ipairs(extmarks) do
+        if mark[4] and mark[4].hl_group == 'Normal' then
+          has_normal = true
+          break
+        end
+      end
+      assert.is_true(has_normal)
+      delete_buffer(bufnr)
+    end)
+
+    it('skips hunks larger than max_lines', function()
+      local lines = { '@@ -1,100 +1,101 @@' }
+      local hunk_lines = {}
+      for i = 1, 600 do
+        table.insert(lines, ' line ' .. i)
+        table.insert(hunk_lines, ' line ' .. i)
+      end
+
+      local bufnr = create_buffer(lines)
+      local hunk = {
+        filename = 'test.lua',
+        lang = 'lua',
+        start_line = 1,
+        lines = hunk_lines,
+      }
+
+      highlight.highlight_hunk(bufnr, ns, hunk, 500, false, false)
+
+      local extmarks = get_extmarks(bufnr)
+      assert.are.equal(0, #extmarks)
+      delete_buffer(bufnr)
+    end)
+
+    it('does nothing for nil lang', function()
+      local bufnr = create_buffer({
+        '@@ -1,1 +1,2 @@',
+        ' some content',
+        '+more content',
+      })
+
+      local hunk = {
+        filename = 'test.unknown',
+        lang = nil,
+        start_line = 1,
+        lines = { ' some content', '+more content' },
+      }
+
+      highlight.highlight_hunk(bufnr, ns, hunk, 500, false, false)
+
+      local extmarks = get_extmarks(bufnr)
+      assert.are.equal(0, #extmarks)
+      delete_buffer(bufnr)
+    end)
+
+    it('highlights header context when enabled', function()
+      local bufnr = create_buffer({
+        '@@ -10,3 +10,4 @@ function hello()',
+        ' local x = 1',
+        '+local y = 2',
+      })
+
+      local hunk = {
+        filename = 'test.lua',
+        lang = 'lua',
+        start_line = 1,
+        header_context = 'function hello()',
+        header_context_col = 18,
+        lines = { ' local x = 1', '+local y = 2' },
+      }
+
+      highlight.highlight_hunk(bufnr, ns, hunk, 500, true, false)
+
+      local extmarks = get_extmarks(bufnr)
+      local has_header_extmark = false
+      for _, mark in ipairs(extmarks) do
+        if mark[2] == 0 then
+          has_header_extmark = true
+          break
+        end
+      end
+      assert.is_true(has_header_extmark)
+      delete_buffer(bufnr)
+    end)
+
+    it('does not highlight header when disabled', function()
+      local bufnr = create_buffer({
+        '@@ -10,3 +10,4 @@ function hello()',
+        ' local x = 1',
+      })
+
+      local hunk = {
+        filename = 'test.lua',
+        lang = 'lua',
+        start_line = 1,
+        header_context = 'function hello()',
+        header_context_col = 18,
+        lines = { ' local x = 1' },
+      }
+
+      highlight.highlight_hunk(bufnr, ns, hunk, 500, false, false)
+
+      local extmarks = get_extmarks(bufnr)
+      local header_extmarks = 0
+      for _, mark in ipairs(extmarks) do
+        if mark[2] == 0 then
+          header_extmarks = header_extmarks + 1
+        end
+      end
+      assert.are.equal(0, header_extmarks)
+      delete_buffer(bufnr)
+    end)
+
+    it('handles empty hunk lines', function()
+      local bufnr = create_buffer({
+        '@@ -1,0 +1,0 @@',
+      })
+
+      local hunk = {
+        filename = 'test.lua',
+        lang = 'lua',
+        start_line = 1,
+        lines = {},
+      }
+
+      assert.has_no.errors(function()
+        highlight.highlight_hunk(bufnr, ns, hunk, 500, false, false)
+      end)
+      delete_buffer(bufnr)
+    end)
+
+    it('handles code that is just whitespace', function()
+      local bufnr = create_buffer({
+        '@@ -1,1 +1,2 @@',
+        ' ',
+        '+  ',
+      })
+
+      local hunk = {
+        filename = 'test.lua',
+        lang = 'lua',
+        start_line = 1,
+        lines = { ' ', '+  ' },
+      }
+
+      assert.has_no.errors(function()
+        highlight.highlight_hunk(bufnr, ns, hunk, 500, false, false)
+      end)
+      delete_buffer(bufnr)
+    end)
+  end)
+end)