feat(list): add SetFilterText and SetFilterState (#335)

* Add SetFilterText and SetFilterState

* make linter happy

* make SetFilterState state not hardcoded

* tests for SetFilterText and SetFilterState

* fix small typo

---------

Co-authored-by: k-x7 <97758178+k-x7@users.noreply.github.com>

list/list.go

@@ -10,15 +10,16 @@ import (
 	"strings"
 	"time"
 
+	tea "github.com/charmbracelet/bubbletea"
+	"github.com/charmbracelet/lipgloss"
+	"github.com/charmbracelet/x/ansi"
+	"github.com/sahilm/fuzzy"
+
 	"github.com/charmbracelet/bubbles/help"
 	"github.com/charmbracelet/bubbles/key"
 	"github.com/charmbracelet/bubbles/paginator"
 	"github.com/charmbracelet/bubbles/spinner"
 	"github.com/charmbracelet/bubbles/textinput"
-	tea "github.com/charmbracelet/bubbletea"
-	"github.com/charmbracelet/lipgloss"
-	"github.com/charmbracelet/x/ansi"
-	"github.com/sahilm/fuzzy"
 )
 
 // Item is an item that appears in the list.
@@ -269,6 +270,34 @@ func (m *Model) SetShowTitle(v bool) {
 	m.updatePagination()
 }
 
+// SetFilterText explicitly sets the filter text without relying on user input.
+// It also sets the filterState to a sane default of FilterApplied, but this
+// can be changed with SetFilterState
+func (m *Model) SetFilterText(filter string) {
+	m.filterState = Filtering
+	m.FilterInput.SetValue(filter)
+	cmd := filterItems(*m)
+	msg := cmd()
+	fmm, _ := msg.(FilterMatchesMsg)
+	m.filteredItems = filteredItems(fmm)
+	m.filterState = FilterApplied
+	m.Paginator.Page = 0
+	m.cursor = 0
+	m.FilterInput.CursorEnd()
+	m.updatePagination()
+	m.updateKeybindings()
+}
+
+// Helper method for setting the filtering state manually
+func (m *Model) SetFilterState(state FilterState) {
+	m.Paginator.Page = 0
+	m.cursor = 0
+	m.filterState = state
+	m.FilterInput.CursorEnd()
+	m.FilterInput.Focus()
+	m.updateKeybindings()
+}
+
 // ShowTitle returns whether or not the title bar is set to be rendered.
 func (m Model) ShowTitle() bool {
 	return m.showTitle

list/list_test.go

@@ -3,6 +3,7 @@ package list
 import (
 	"fmt"
 	"io"
+	"reflect"
 	"strings"
 	"testing"
 
@@ -11,7 +12,7 @@ import (
 
 type item string
 
-func (i item) FilterValue() string { return "" }
+func (i item) FilterValue() string { return string(i) }
 
 type itemDelegate struct{}
 
@@ -72,3 +73,65 @@ func TestCustomStatusBarItemName(t *testing.T) {
 		t.Fatalf("Error: expected view to contain %s", expected)
 	}
 }
+
+func TestSetFilterText(t *testing.T) {
+	tc := []Item{item("foo"), item("bar"), item("baz")}
+
+	list := New(tc, itemDelegate{}, 10, 10)
+	list.SetFilterText("ba")
+
+	list.SetFilterState(Unfiltered)
+	expected := tc
+	// TODO: replace with slices.Equal() when project move to go1.18 or later
+	if !reflect.DeepEqual(list.VisibleItems(), expected) {
+		t.Fatalf("Error: expected view to contain only %s", expected)
+	}
+
+	list.SetFilterState(Filtering)
+	expected = []Item{item("bar"), item("baz")}
+	if !reflect.DeepEqual(list.VisibleItems(), expected) {
+		t.Fatalf("Error: expected view to contain only %s", expected)
+	}
+
+	list.SetFilterState(FilterApplied)
+	if !reflect.DeepEqual(list.VisibleItems(), expected) {
+		t.Fatalf("Error: expected view to contain only %s", expected)
+	}
+}
+
+func TestSetFilterState(t *testing.T) {
+	tc := []Item{item("foo"), item("bar"), item("baz")}
+
+	list := New(tc, itemDelegate{}, 10, 10)
+	list.SetFilterText("ba")
+
+	list.SetFilterState(Unfiltered)
+	expected, notExpected := "up", "clear filter"
+
+	lines := strings.Split(list.View(), "\n")
+	footer := lines[len(lines)-1]
+
+	if !strings.Contains(footer, expected) || strings.Contains(footer, notExpected) {
+		t.Fatalf("Error: expected view to contain '%s' not '%s'", expected, notExpected)
+	}
+
+	list.SetFilterState(Filtering)
+	expected, notExpected = "filter", "more"
+
+	lines = strings.Split(list.View(), "\n")
+	footer = lines[len(lines)-1]
+
+	if !strings.Contains(footer, expected) || strings.Contains(footer, notExpected) {
+		t.Fatalf("Error: expected view to contain '%s' not '%s'", expected, notExpected)
+	}
+
+	list.SetFilterState(FilterApplied)
+	expected = "clear"
+
+	lines = strings.Split(list.View(), "\n")
+	footer = lines[len(lines)-1]
+
+	if !strings.Contains(footer, expected) {
+		t.Fatalf("Error: expected view to contain '%s'", expected)
+	}
+}