Set groundwork for better disabled reasons with range select

Something dumb that we're currently doing is expecting list items
to define an ID method which returns a string. We use that when copying
items to clipboard with ctrl+o and when getting a ref name for diffing.

This commit gets us a little deeper into that hole by explicitly requiring
list items to implement that method so that we can easily use the new
helper functions in list_controller_trait.go.

In future we need to just remove the whole ID thing entirely but I'm too
lazy to do that right now.

pkg/gui/controllers/basic_commits_controller.go

@@ -16,6 +16,7 @@ type ContainsCommits interface {
 	types.Context
 	types.IListContext
 	GetSelected() *models.Commit
+	GetSelectedItems() ([]*models.Commit, int, int)
 	GetCommits() []*models.Commit
 	GetSelectedLineIdx() int
 }
@@ -36,6 +37,7 @@ func NewBasicCommitsController(c *ControllerCommon, context ContainsCommits) *Ba
 			c,
 			context,
 			context.GetSelected,
+			context.GetSelectedItems,
 		),
 	}
 }

pkg/gui/controllers/bisect_controller.go

@@ -30,6 +30,7 @@ func NewBisectController(
 			c,
 			c.Contexts().LocalCommits,
 			c.Contexts().LocalCommits.GetSelected,
+			c.Contexts().LocalCommits.GetSelectedItems,
 		),
 	}
 }

pkg/gui/controllers/branches_controller.go

@@ -33,6 +33,7 @@ func NewBranchesController(
 			c,
 			c.Contexts().Branches,
 			c.Contexts().Branches.GetSelected,
+			c.Contexts().Branches.GetSelectedItems,
 		),
 	}
 }

pkg/gui/controllers/commits_files_controller.go

@@ -28,6 +28,7 @@ func NewCommitFilesController(
 			c,
 			c.Contexts().CommitFiles,
 			c.Contexts().CommitFiles.GetSelected,
+			c.Contexts().CommitFiles.GetSelectedItems,
 		),
 	}
 }

pkg/gui/controllers/files_controller.go

@@ -28,6 +28,7 @@ func NewFilesController(
 			c,
 			c.Contexts().Files,
 			c.Contexts().Files.GetSelected,
+			c.Contexts().Files.GetSelectedItems,
 		),
 	}
 }

pkg/gui/controllers/files_remove_controller.go

@@ -28,6 +28,7 @@ func NewFilesRemoveController(
 			c,
 			c.Contexts().Files,
 			c.Contexts().Files.GetSelected,
+			c.Contexts().Files.GetSelectedItems,
 		),
 	}
 }

pkg/gui/controllers/git_flow_controller.go

@@ -25,6 +25,7 @@ func NewGitFlowController(
 			c,
 			c.Contexts().Branches,
 			c.Contexts().Branches.GetSelected,
+			c.Contexts().Branches.GetSelectedItems,
 		),
 		c: c,
 	}

pkg/gui/controllers/list_controller_trait.go

@@ -6,20 +6,23 @@ import "github.com/jesseduffield/lazygit/pkg/gui/types"
 // ensuring a single item is selected, etc.
 
 type ListControllerTrait[T comparable] struct {
-	c           *ControllerCommon
-	context     types.IListContext
-	getSelected func() T
+	c                *ControllerCommon
+	context          types.IListContext
+	getSelectedItem  func() T
+	getSelectedItems func() ([]T, int, int)
 }
 
 func NewListControllerTrait[T comparable](
 	c *ControllerCommon,
 	context types.IListContext,
 	getSelected func() T,
+	getSelectedItems func() ([]T, int, int),
 ) *ListControllerTrait[T] {
 	return &ListControllerTrait[T]{
-		c:           c,
-		context:     context,
-		getSelected: getSelected,
+		c:                c,
+		context:          context,
+		getSelectedItem:  getSelected,
+		getSelectedItems: getSelectedItems,
 	}
 }
 
@@ -47,7 +50,7 @@ func (self *ListControllerTrait[T]) singleItemSelected(callbacks ...func(T) *typ
 		}
 
 		var zeroValue T
-		item := self.getSelected()
+		item := self.getSelectedItem()
 		if item == zeroValue {
 			return &types.DisabledReason{Text: self.c.Tr.NoItemSelected}
 		}
@@ -62,11 +65,46 @@ func (self *ListControllerTrait[T]) singleItemSelected(callbacks ...func(T) *typ
 	}
 }
 
+// Ensures that at least one item is selected.
+func (self *ListControllerTrait[T]) itemRangeSelected(callbacks ...func([]T, int, int) *types.DisabledReason) func() *types.DisabledReason {
+	return func() *types.DisabledReason {
+		items, startIdx, endIdx := self.getSelectedItems()
+		if len(items) == 0 {
+			return &types.DisabledReason{Text: self.c.Tr.NoItemSelected}
+		}
+
+		for _, callback := range callbacks {
+			if reason := callback(items, startIdx, endIdx); reason != nil {
+				return reason
+			}
+		}
+
+		return nil
+	}
+}
+
+func (self *ListControllerTrait[T]) itemsSelected(callbacks ...func([]T) *types.DisabledReason) func() *types.DisabledReason { //nolint:unused
+	return func() *types.DisabledReason {
+		items, _, _ := self.getSelectedItems()
+		if len(items) == 0 {
+			return &types.DisabledReason{Text: self.c.Tr.NoItemSelected}
+		}
+
+		for _, callback := range callbacks {
+			if reason := callback(items); reason != nil {
+				return reason
+			}
+		}
+
+		return nil
+	}
+}
+
 // Passes the selected item to the callback. Used for handler functions.
 func (self *ListControllerTrait[T]) withItem(callback func(T) error) func() error {
 	return func() error {
 		var zeroValue T
-		commit := self.getSelected()
+		commit := self.getSelectedItem()
 		if commit == zeroValue {
 			return self.c.ErrorMsg(self.c.Tr.NoItemSelected)
 		}
@@ -75,12 +113,35 @@ func (self *ListControllerTrait[T]) withItem(callback func(T) error) func() erro
 	}
 }
 
+func (self *ListControllerTrait[T]) withItems(callback func([]T) error) func() error {
+	return func() error {
+		items, _, _ := self.getSelectedItems()
+		if len(items) == 0 {
+			return self.c.ErrorMsg(self.c.Tr.NoItemSelected)
+		}
+
+		return callback(items)
+	}
+}
+
+// like withItems but also passes the start and end index of the selection
+func (self *ListControllerTrait[T]) withItemsRange(callback func([]T, int, int) error) func() error {
+	return func() error {
+		items, startIdx, endIdx := self.getSelectedItems()
+		if len(items) == 0 {
+			return self.c.ErrorMsg(self.c.Tr.NoItemSelected)
+		}
+
+		return callback(items, startIdx, endIdx)
+	}
+}
+
 // Like withItem, but doesn't show an error message if no item is selected.
 // Use this for click actions (it's a no-op to click empty space)
 func (self *ListControllerTrait[T]) withItemGraceful(callback func(T) error) func() error {
 	return func() error {
 		var zeroValue T
-		commit := self.getSelected()
+		commit := self.getSelectedItem()
 		if commit == zeroValue {
 			return nil
 		}

pkg/gui/controllers/menu_controller.go

@@ -22,6 +22,7 @@ func NewMenuController(
 			c,
 			c.Contexts().Menu,
 			c.Contexts().Menu.GetSelected,
+			c.Contexts().Menu.GetSelectedItems,
 		),
 		c: c,
 	}

pkg/gui/controllers/reflog_commits_controller.go

@@ -23,6 +23,7 @@ func NewReflogCommitsController(
 			c,
 			c.Contexts().ReflogCommits,
 			c.Contexts().ReflogCommits.GetSelected,
+			c.Contexts().ReflogCommits.GetSelectedItems,
 		),
 		c: c,
 	}

pkg/gui/controllers/remote_branches_controller.go

@@ -26,6 +26,7 @@ func NewRemoteBranchesController(
 			c,
 			c.Contexts().RemoteBranches,
 			c.Contexts().RemoteBranches.GetSelected,
+			c.Contexts().RemoteBranches.GetSelectedItems,
 		),
 		c: c,
 	}

pkg/gui/controllers/remotes_controller.go

@@ -32,6 +32,7 @@ func NewRemotesController(
 			c,
 			c.Contexts().Remotes,
 			c.Contexts().Remotes.GetSelected,
+			c.Contexts().Remotes.GetSelectedItems,
 		),
 		c:                 c,
 		setRemoteBranches: setRemoteBranches,

pkg/gui/controllers/stash_controller.go

@@ -24,6 +24,7 @@ func NewStashController(
 			c,
 			c.Contexts().Stash,
 			c.Contexts().Stash.GetSelected,
+			c.Contexts().Stash.GetSelectedItems,
 		),
 		c: c,
 	}

pkg/gui/controllers/sub_commits_controller.go

@@ -24,6 +24,7 @@ func NewSubCommitsController(
 			c,
 			c.Contexts().SubCommits,
 			c.Contexts().SubCommits.GetSelected,
+			c.Contexts().SubCommits.GetSelectedItems,
 		),
 		c: c,
 	}

pkg/gui/controllers/submodules_controller.go

@@ -29,6 +29,7 @@ func NewSubmodulesController(
 			c,
 			c.Contexts().Submodules,
 			c.Contexts().Submodules.GetSelected,
+			c.Contexts().Submodules.GetSelectedItems,
 		),
 		c: c,
 	}

pkg/gui/controllers/suggestions_controller.go

@@ -22,6 +22,7 @@ func NewSuggestionsController(
 			c,
 			c.Contexts().Suggestions,
 			c.Contexts().Suggestions.GetSelected,
+			c.Contexts().Suggestions.GetSelectedItems,
 		),
 		c: c,
 	}

pkg/gui/controllers/switch_to_diff_files_controller.go

@@ -36,6 +36,9 @@ func NewSwitchToDiffFilesController(
 			c,
 			context,
 			context.GetSelectedRef,
+			func() ([]types.Ref, int, int) {
+				panic("Not implemented")
+			},
 		),
 		c:                c,
 		context:          context,

pkg/gui/controllers/switch_to_sub_commits_controller.go

@@ -32,6 +32,9 @@ func NewSwitchToSubCommitsController(
 			c,
 			context,
 			context.GetSelectedRef,
+			func() ([]types.Ref, int, int) {
+				panic("Not implemented")
+			},
 		),
 		c:       c,
 		context: context,

pkg/gui/controllers/tags_controller.go

@@ -25,6 +25,7 @@ func NewTagsController(
 			c,
 			c.Contexts().Tags,
 			c.Contexts().Tags.GetSelected,
+			c.Contexts().Tags.GetSelectedItems,
 		),
 		c: c,
 	}

pkg/gui/controllers/worktree_options_controller.go

@@ -26,6 +26,7 @@ func NewWorktreeOptionsController(c *ControllerCommon, context CanViewWorktreeOp
 			c,
 			context,
 			context.GetSelectedItemId,
+			context.GetSelectedItemIds,
 		),
 		c:       c,
 		context: context,

pkg/gui/controllers/worktrees_controller.go

@@ -28,6 +28,7 @@ func NewWorktreesController(
 			c,
 			c.Contexts().Worktrees,
 			c.Contexts().Worktrees.GetSelected,
+			c.Contexts().Worktrees.GetSelectedItems,
 		),
 		c: c,
 	}