fix: handle git diff and message send failures gracefully

lua/opencode/commands/handlers/workflow.lua

@@ -362,7 +362,9 @@ M.actions.submit_input_prompt = Promise.async(function()
     return
   end
 
-  require('opencode.services.messaging').send_message(input_content)
+  require('opencode.services.messaging').send_message(input_content):catch(function(err)
+    require('opencode.log').notify('Error sending message: ' .. vim.inspect(err), vim.log.levels.ERROR)
+  end)
   if config.ui.input.auto_hide and not input_window.is_hidden() then
     input_window._hide()
   end

lua/opencode/context/base_context.lua

@@ -263,12 +263,14 @@ M.get_git_diff = Promise.async(function(context_config)
     return nil
   end
 
-  return Promise.system({ 'git', 'diff', '--cached', '--minimal' }):and_then(function(output)
-    if output == '' then
-      return nil
-    end
-    return output.stdout
+  -- Optional context must not prevent sending from non-repositories or after Git failures.
+  local ok, output = pcall(function()
+    return Promise.system({ 'git', 'diff', '--cached', '--minimal' }):await()
   end)
+  if not ok or output.stdout == '' then
+    return nil
+  end
+  return output.stdout
 end)
 
 ---@param file table

tests/unit/api_spec.lua

@@ -382,7 +382,7 @@ describe('opencode.api', function()
           local after_run_stub = stub(messaging, 'after_run')
           local send_message_stub = stub(messaging, 'send_message').invokes(function(prompt)
             require('opencode.services.messaging').after_run(prompt)
-            return true
+            return resolved(true)
           end)
           local take_input_stub = stub(input_window, 'take_input').returns('hello')
           local is_hidden_stub = stub(input_window, 'is_hidden').returns(true)

tests/unit/base_context_git_diff_spec.lua

@@ -0,0 +1,65 @@
+local assert = require('luassert')
+local stub = require('luassert.stub')
+local base_context = require('opencode.context.base_context')
+local Promise = require('opencode.promise')
+
+describe('Git diff context', function()
+  local system
+  local enabled = { git_diff = { enabled = true } }
+
+  before_each(function()
+    system = stub(Promise, 'system')
+  end)
+
+  after_each(function()
+    system:revert()
+  end)
+
+  it('does not run Git when disabled', function()
+    assert.is_nil(base_context.get_git_diff({ git_diff = { enabled = false } }):wait())
+    assert.stub(system).was_not_called()
+  end)
+
+  it('returns staged changes', function()
+    system.returns(Promise.new():resolve({ stdout = 'staged diff' }))
+    assert.equals('staged diff', base_context.get_git_diff(enabled):wait())
+    assert.stub(system).was_called_with({ 'git', 'diff', '--cached', '--minimal' })
+  end)
+
+  it('returns nil for an empty diff', function()
+    system.returns(Promise.new():resolve({ stdout = '' }))
+    assert.is_nil(base_context.get_git_diff(enabled):wait())
+  end)
+
+  it('returns nil when Git rejects', function()
+    system.returns(Promise.new():reject({ code = 129, stderr = 'not a git repository' }))
+    assert.is_nil(base_context.get_git_diff(enabled):wait())
+  end)
+
+  it('returns nil when Git cannot start', function()
+    system.invokes(function()
+      error('Git executable not found')
+    end)
+    assert.is_nil(base_context.get_git_diff(enabled):wait())
+  end)
+end)
+
+describe('Git diff context outside a repository', function()
+  local cwd, directory
+
+  before_each(function()
+    cwd = vim.fn.getcwd()
+    directory = '/tmp/opencode/git-diff-' .. vim.uv.hrtime()
+    vim.fn.mkdir(directory, 'p')
+    vim.fn.chdir(directory)
+  end)
+
+  after_each(function()
+    vim.fn.chdir(cwd)
+    vim.fn.delete(directory, 'd')
+  end)
+
+  it('resolves nil instead of rejecting', function()
+    assert.is_nil(base_context.get_git_diff({ git_diff = { enabled = true } }):wait())
+  end)
+end)

tests/unit/commands_handlers_workflow_spec.lua

@@ -32,7 +32,7 @@ describe('opencode.commands.handlers.workflow', function()
       state.store.set_raw('windows', { input_buf = buf, input_win = vim.api.nvim_get_current_win() })
       state.store.set_raw('display_route', nil)
       config.ui.input.auto_hide = true
-      send_message = stub(require('opencode.services.messaging'), 'send_message').returns(false)
+      send_message = stub(require('opencode.services.messaging'), 'send_message').returns(Promise.new():resolve(false))
       hide = stub(input_window, '_hide')
       hidden = stub(input_window, 'is_hidden').returns(false)
       get_key = stub(config, 'get_key_for_function').returns('/')
@@ -76,6 +76,22 @@ describe('opencode.commands.handlers.workflow', function()
       assert.stub(hide).was_called(1)
     end)
 
+    it('reports asynchronous send failures without waiting to auto-hide', function()
+      local pending = Promise.new()
+      send_message.returns(pending)
+      submit({ 'hello' })
+      assert.stub(hide).was_called(1)
+      assert.stub(notify).was_not_called()
+
+      pending:reject('context preparation failed')
+      assert.is_true(vim.wait(1000, function()
+        return #notify.calls > 0
+      end))
+      assert
+        .stub(notify)
+        .was_called_with('[opencode.nvim] Error sending message: ' .. vim.inspect('context preparation failed'), vim.log.levels.ERROR)
+    end)
+
     it('clears empty input without sending or hiding', function()
       submit({ '' })
       assert.stub(send_message).was_not_called()