Recover from internal errors without crashing

diff --git a/cmd/micro/micro.go b/cmd/micro/micro.go
index b1e70187a4b982e8cae6a197906f98787afcbdcc..19ab25d583a7db6fd4137020f339fe36b20b53fe 100644 (file)
--- a/cmd/micro/micro.go
+++ b/cmd/micro/micro.go
@@ -11,6 +11,7 @@ import (
 
        "github.com/go-errors/errors"
        isatty "github.com/mattn/go-isatty"
+       lua "github.com/yuin/gopher-lua"
        "github.com/zyedidia/micro/internal/action"
        "github.com/zyedidia/micro/internal/buffer"
        "github.com/zyedidia/micro/internal/config"
@@ -218,9 +219,6 @@ func main() {
 
        screen.Init()
 
-       // If we have an error, we can exit cleanly and not completely
-       // mess up the terminal being worked in
-       // In other words we need to shut down tcell before the program crashes
        defer func() {
                if err := recover(); err != nil {
                        screen.Screen.Fini()
@@ -284,48 +282,64 @@ func main() {
                <-screen.DrawChan
        }
 
-       var event tcell.Event
-
        // wait for initial resize event
        select {
-       case event = <-events:
+       case event := <-events:
                action.Tabs.HandleEvent(event)
        case <-time.After(10 * time.Millisecond):
                // time out after 10ms
        }
 
+       // Since this loop is very slow (waits for user input every time) it's
+       // okay to be inefficient and run it via a function every time
+       // We do this so we can recover from panics without crashing the editor
        for {
-               // Display everything
-               screen.Screen.Fill(' ', config.DefStyle)
-               screen.Screen.HideCursor()
-               action.Tabs.Display()
-               for _, ep := range action.MainTab().Panes {
-                       ep.Display()
-               }
-               action.MainTab().Display()
-               action.InfoBar.Display()
-               screen.Screen.Show()
-
-               event = nil
-
-               // Check for new events
-               select {
-               case f := <-shell.Jobs:
-                       // If a new job has finished while running in the background we should execute the callback
-                       f.Function(f.Output, f.Args)
-               case <-config.Autosave:
-                       for _, b := range buffer.OpenBuffers {
-                               b.Save()
+               DoEvent()
+       }
+}
+
+// DoEvent runs the main action loop of the editor
+func DoEvent() {
+       var event tcell.Event
+
+       // recover from errors without crashing the editor
+       defer func() {
+               if err := recover(); err != nil {
+                       if e, ok := err.(*lua.ApiError); ok {
+                               screen.TermMessage("Lua API error:", e)
+                       } else {
+                               screen.TermMessage("Micro encountered an error:", errors.Wrap(err, 2).ErrorStack(), "\nIf you can reproduce this error, please report it at https://github.com/zyedidia/micro/issues")
                        }
-               case <-shell.CloseTerms:
-               case event = <-events:
-               case <-screen.DrawChan:
                }
+       }()
+       // Display everything
+       screen.Screen.Fill(' ', config.DefStyle)
+       screen.Screen.HideCursor()
+       action.Tabs.Display()
+       for _, ep := range action.MainTab().Panes {
+               ep.Display()
+       }
+       action.MainTab().Display()
+       action.InfoBar.Display()
+       screen.Screen.Show()
 
-               if action.InfoBar.HasPrompt {
-                       action.InfoBar.HandleEvent(event)
-               } else {
-                       action.Tabs.HandleEvent(event)
+       // Check for new events
+       select {
+       case f := <-shell.Jobs:
+               // If a new job has finished while running in the background we should execute the callback
+               f.Function(f.Output, f.Args)
+       case <-config.Autosave:
+               for _, b := range buffer.OpenBuffers {
+                       b.Save()
                }
+       case <-shell.CloseTerms:
+       case event = <-events:
+       case <-screen.DrawChan:
+       }
+
+       if action.InfoBar.HasPrompt {
+               action.InfoBar.HandleEvent(event)
+       } else {
+               action.Tabs.HandleEvent(event)
        }
 }

diff --git a/go.sum b/go.sum
index 9141da9251d6122c839a196600da70f884d33b04..1669b93a03fc74304d294911a9579553b43d78ff 100644 (file)
--- a/go.sum
+++ b/go.sum
@@ -50,8 +50,6 @@ github.com/zyedidia/poller v1.0.1 h1:Tt9S3AxAjXwWGNiC2TUdRJkQDZSzCBNVQ4xXiQ7440s
 github.com/zyedidia/poller v1.0.1/go.mod h1:vZXJOHGDcuK08GXhF6IAY0ZFd2WcgOR5DOTp84Uk5eE=
 github.com/zyedidia/pty v2.0.0+incompatible h1:Ou5vXL6tvjst+RV8sUFISbuKDnUJPhnpygApMFGweqw=
 github.com/zyedidia/pty v2.0.0+incompatible/go.mod h1:4y9l9yJZNxRa7GB/fB+mmDmGkG3CqmzLf4vUxGGotEA=
-github.com/zyedidia/tcell v1.4.2 h1:JWMDs6O1saINPIR5M3kNqlWJwkfnBZeZDZszEJi3BW8=
-github.com/zyedidia/tcell v1.4.2/go.mod h1:HhlbMSCcGX15rFDB+Q1Lk3pKEOocsCUAQC3zhZ9sadA=
 github.com/zyedidia/tcell v1.4.3 h1:s0nmxj22Jj+vyt4nVmnB6kbnwRxEay1zfS0j8IsbtfI=
 github.com/zyedidia/tcell v1.4.3/go.mod h1:HhlbMSCcGX15rFDB+Q1Lk3pKEOocsCUAQC3zhZ9sadA=
 github.com/zyedidia/terminal v0.0.0-20180726154117-533c623e2415 h1:752dTQ5OatJ9M5ULK2+9lor+nzyZz+LYDo3WGngg3Rc=