Don't allow empty input in most prompts (#5043)

Most of our prompts don't (shouldn't) allow empty input, but most
callers didn't check, and would run into cryptic errors when the user
pressed enter at an empty prompt (e.g. when creating a new branch). Now
we simply don't allow hitting enter in this case, and show an error
toast instead.

This behavior is opt-out, because there are a few cases where empty
input is supported (e.g. creating a stash).

Author: stefanhaller

pkg/gui/controllers/diffing_menu_action.go

@@ -2,7 +2,6 @@ package controllers
 
 import (
 	"fmt"
-	"strings"
 
 	"github.com/jesseduffield/lazygit/pkg/gui/modes/diffing"
 	"github.com/jesseduffield/lazygit/pkg/gui/types"
@@ -38,7 +37,7 @@ func (self *DiffingMenuAction) Call() error {
 					Title:               self.c.Tr.EnterRefName,
 					FindSuggestionsFunc: self.c.Helpers().Suggestions.GetRefsSuggestionsFunc(),
 					HandleConfirm: func(response string) error {
-						self.c.Modes().Diffing.Ref = strings.TrimSpace(response)
+						self.c.Modes().Diffing.Ref = response
 						self.c.Refresh(types.RefreshOptions{Mode: types.ASYNC})
 						return nil
 					},

pkg/gui/controllers/files_controller.go

@@ -1211,6 +1211,7 @@ func (self *FilesController) handleStashSave(stashFunc func(message string) erro
 			self.c.Refresh(types.RefreshOptions{Scope: []types.RefreshableView{types.STASH, types.FILES}})
 			return nil
 		},
+		AllowEmptyInput: true,
 	})
 
 	return nil

pkg/gui/controllers/filtering_menu_action.go

@@ -2,7 +2,6 @@ package controllers
 
 import (
 	"fmt"
-	"strings"
 
 	"github.com/jesseduffield/lazygit/pkg/gui/controllers/helpers"
 	"github.com/jesseduffield/lazygit/pkg/gui/types"
@@ -66,7 +65,7 @@ func (self *FilteringMenuAction) Call() error {
 				FindSuggestionsFunc: self.c.Helpers().Suggestions.GetFilePathSuggestionsFunc(),
 				Title:               self.c.Tr.EnterFileName,
 				HandleConfirm: func(response string) error {
-					return self.setFilteringPath(strings.TrimSpace(response))
+					return self.setFilteringPath(response)
 				},
 			})
 
@@ -82,7 +81,7 @@ func (self *FilteringMenuAction) Call() error {
 				FindSuggestionsFunc: self.c.Helpers().Suggestions.GetAuthorsSuggestionsFunc(),
 				Title:               self.c.Tr.EnterAuthor,
 				HandleConfirm: func(response string) error {
-					return self.setFilteringAuthor(strings.TrimSpace(response))
+					return self.setFilteringAuthor(response)
 				},
 			})
 

pkg/gui/controllers/helpers/confirmation_helper.go

@@ -24,7 +24,33 @@ func NewConfirmationHelper(c *HelperCommon) *ConfirmationHelper {
 // This file is for the rendering of confirmation panels along with setting and handling associated
 // keybindings.
 
+func (self *ConfirmationHelper) closeAndCallConfirmationFunction(cancel goContext.CancelFunc, function func() error) error {
+	cancel()
+
+	self.c.Context().Pop()
+
+	if function != nil {
+		if err := function(); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
 func (self *ConfirmationHelper) wrappedConfirmationFunction(cancel goContext.CancelFunc, function func() error) func() error {
+	return func() error {
+		return self.closeAndCallConfirmationFunction(cancel, function)
+	}
+}
+
+func (self *ConfirmationHelper) wrappedPromptConfirmationFunction(
+	cancel goContext.CancelFunc,
+	function func(string) error,
+	getResponse func() string,
+	allowEmptyInput bool,
+	preserveWhitespace bool,
+) func() error {
 	return func() error {
 		if self.c.GocuiGui().IsPasting {
 			// The user is pasting multi-line text into a prompt; we don't want to handle the
@@ -34,26 +60,22 @@ func (self *ConfirmationHelper) wrappedConfirmationFunction(cancel goContext.Can
 			return nil
 		}
 
-		cancel()
-
-		self.c.Context().Pop()
+		response := getResponse()
+		if !preserveWhitespace {
+			response = strings.TrimSpace(response)
+		}
 
-		if function != nil {
-			if err := function(); err != nil {
-				return err
-			}
+		if response == "" && !allowEmptyInput {
+			self.c.ErrorToast(self.c.Tr.PromptInputCannotBeEmptyToast)
+			return nil
 		}
 
-		return nil
+		return self.closeAndCallConfirmationFunction(cancel, func() error {
+			return function(response)
+		})
 	}
 }
 
-func (self *ConfirmationHelper) wrappedPromptConfirmationFunction(cancel goContext.CancelFunc, function func(string) error, getResponse func() string) func() error {
-	return self.wrappedConfirmationFunction(cancel, func() error {
-		return function(getResponse())
-	})
-}
-
 func (self *ConfirmationHelper) DeactivateConfirmation() {
 	self.c.Mutexes().PopupMutex.Lock()
 	self.c.State().GetRepoState().SetCurrentPopupOpts(nil)
@@ -229,12 +251,15 @@ func (self *ConfirmationHelper) setConfirmationKeyBindings(cancel goContext.Canc
 
 func (self *ConfirmationHelper) setPromptKeyBindings(cancel goContext.CancelFunc, opts types.CreatePopupPanelOpts) {
 	onConfirm := self.wrappedPromptConfirmationFunction(cancel, opts.HandleConfirmPrompt,
-		func() string { return self.c.Views().Prompt.TextArea.GetContent() })
+		func() string { return self.c.Views().Prompt.TextArea.GetContent() },
+		opts.AllowEmptyInput, opts.PreserveWhitespace)
 
 	onSuggestionConfirm := self.wrappedPromptConfirmationFunction(
 		cancel,
 		opts.HandleConfirmPrompt,
 		self.getSelectedSuggestionValue,
+		opts.AllowEmptyInput,
+		opts.PreserveWhitespace,
 	)
 
 	onClose := self.wrappedConfirmationFunction(cancel, opts.HandleClose)

pkg/gui/controllers/helpers/credentials_helper.go

@@ -41,6 +41,7 @@ func (self *CredentialsHelper) PromptUserForCredential(passOrUname oscommands.Cr
 
 				return nil
 			},
+			AllowEmptyInput: true,
 		})
 
 		return nil

pkg/gui/controllers/helpers/worktree_helper.go

@@ -130,23 +130,21 @@ func (self *WorktreeHelper) NewWorktreeCheckout(base string, canCheckoutBase boo
 
 						return f()
 					},
+					AllowEmptyInput: true,
 				})
 
 				return nil
 			}
 
-			// prompt for the new branch name where a blank means we just check out the branch
+			// prompt for the new branch name
 			self.c.Prompt(types.PromptOpts{
 				Title: self.c.Tr.NewBranchName,
 				HandleConfirm: func(branchName string) error {
-					if branchName == "" {
-						return errors.New(self.c.Tr.BranchNameCannotBeBlank)
-					}
-
 					opts.Branch = branchName
 
 					return f()
 				},
+				AllowEmptyInput: false,
 			})
 
 			return nil

pkg/gui/controllers/shell_command_action.go

@@ -19,6 +19,7 @@ func (self *ShellCommandAction) Call() error {
 		Title:               self.c.Tr.ShellCommand,
 		FindSuggestionsFunc: self.GetShellCommandsHistorySuggestionsFunc(),
 		AllowEditSuggestion: true,
+		PreserveWhitespace:  true,
 		HandleConfirm: func(command string) error {
 			if self.shouldSaveCommand(command) {
 				self.c.GetAppState().ShellCommandsHistory = utils.Limit(

pkg/gui/controllers/stash_controller.go

@@ -209,6 +209,7 @@ func (self *StashController) handleRenameStashEntry(stashEntry *models.StashEntr
 			self.c.Refresh(types.RefreshOptions{Scope: []types.RefreshableView{types.STASH}})
 			return nil
 		},
+		AllowEmptyInput: true,
 	})
 
 	return nil

pkg/gui/popup/popup_handler.go

@@ -139,6 +139,8 @@ func (self *PopupHandler) Prompt(opts types.PromptOpts) {
 		HandleDeleteSuggestion: opts.HandleDeleteSuggestion,
 		FindSuggestionsFunc:    opts.FindSuggestionsFunc,
 		AllowEditSuggestion:    opts.AllowEditSuggestion,
+		AllowEmptyInput:        opts.AllowEmptyInput,
+		PreserveWhitespace:     opts.PreserveWhitespace,
 		Mask:                   opts.Mask,
 	})
 }

pkg/gui/services/custom_commands/handler_creator.go

@@ -125,6 +125,8 @@ func (self *HandlerCreator) inputPrompt(prompt *config.CustomCommandPrompt, wrap
 		HandleConfirm: func(str string) error {
 			return wrappedF(str)
 		},
+		AllowEmptyInput:    true,
+		PreserveWhitespace: true,
 	})
 
 	return nil