From 9f0c00d4b6b1c0c55c3e641d04a43b8e3b36e342 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?L=C3=A1szl=C3=B3=20G=C3=96R=C3=96G?= <contact@nergal.xyz>
Date: Sun, 13 Apr 2025 13:53:45 +0200
Subject: [PATCH] feat(filepicker): allow configuring FS

---
 filepicker/filepicker.go      | 17 ++++++---
 filepicker/filepicker_test.go | 68 +++++++++++++++++++++++++++++++++++
 2 files changed, 80 insertions(+), 5 deletions(-)
 create mode 100644 filepicker/filepicker_test.go

diff --git a/filepicker/filepicker.go b/filepicker/filepicker.go
index b749684d6..c849dbaca 100644
--- a/filepicker/filepicker.go
+++ b/filepicker/filepicker.go
@@ -4,6 +4,7 @@ package filepicker
 
 import (
 	"fmt"
+	"io/fs"
 	"os"
 	"path/filepath"
 	"sort"
@@ -25,9 +26,11 @@ func nextID() int {
 
 // New returns a new filepicker model with default styling and key bindings.
 func New() Model {
+	dir, _ := os.Getwd()
 	return Model{
 		id:               nextID(),
 		CurrentDirectory: ".",
+		FS:               os.DirFS(dir),
 		Cursor:           ">",
 		AllowedTypes:     []string{},
 		selected:         0,
@@ -104,6 +107,7 @@ type Styles struct {
 	DisabledSelected lipgloss.Style
 	FileSize         lipgloss.Style
 	EmptyDirectory   lipgloss.Style
+	HelpStyle        lipgloss.Style
 }
 
 // DefaultStyles defines the default styling for the file picker.
@@ -133,6 +137,9 @@ type Model struct {
 	// CurrentDirectory is the directory that the user is currently in.
 	CurrentDirectory string
 
+	// FS is the filesystem the file picker can walk.
+	FS fs.FS
+
 	// AllowedTypes specifies which file types the user may select.
 	// If empty the user may select any file.
 	AllowedTypes []string
@@ -194,9 +201,9 @@ func (m *Model) popView() (int, int, int) {
 	return m.selectedStack.Pop(), m.minStack.Pop(), m.maxStack.Pop()
 }
 
-func (m Model) readDir(path string, showHidden bool) tea.Cmd {
+func (m Model) readDir(fysy fs.FS, path string, showHidden bool) tea.Cmd {
 	return func() tea.Msg {
-		dirEntries, err := os.ReadDir(path)
+		dirEntries, err := fs.ReadDir(fysy, path)
 		if err != nil {
 			return errorMsg{err}
 		}
@@ -239,7 +246,7 @@ func (m Model) Height() int {
 
 // Init initializes the file picker model.
 func (m Model) Init() tea.Cmd {
-	return m.readDir(m.CurrentDirectory, m.ShowHidden)
+	return m.readDir(m.FS, m.CurrentDirectory, m.ShowHidden)
 }
 
 // Update handles user interactions within the file picker model.
@@ -317,7 +324,7 @@ func (m Model) Update(msg tea.Msg) (Model, tea.Cmd) {
 				m.minIdx = 0
 				m.maxIdx = m.Height() - 1
 			}
-			return m, m.readDir(m.CurrentDirectory, m.ShowHidden)
+			return m, m.readDir(m.FS, m.CurrentDirectory, m.ShowHidden)
 		case key.Matches(msg, m.KeyMap.Open):
 			if len(m.files) == 0 {
 				break
@@ -358,7 +365,7 @@ func (m Model) Update(msg tea.Msg) (Model, tea.Cmd) {
 			m.selected = 0
 			m.minIdx = 0
 			m.maxIdx = m.Height() - 1
-			return m, m.readDir(m.CurrentDirectory, m.ShowHidden)
+			return m, m.readDir(m.FS, m.CurrentDirectory, m.ShowHidden)
 		}
 	}
 	return m, nil
diff --git a/filepicker/filepicker_test.go b/filepicker/filepicker_test.go
new file mode 100644
index 000000000..453f09765
--- /dev/null
+++ b/filepicker/filepicker_test.go
@@ -0,0 +1,68 @@
+package filepicker
+
+import (
+	tea "github.com/charmbracelet/bubbletea/v2"
+	"strings"
+	"testing"
+	"testing/fstest"
+)
+
+func TestFS(t *testing.T) {
+	fp := New()
+	fp.FS = fstest.MapFS{
+		"bubbles/help.txt": {Data: []byte("1")},
+		"bubbles/list.txt": {Data: []byte("1")},
+		"charm.sh":         {Data: []byte("   4")},
+		"hello.txt":        {Data: []byte(" 2")},
+		"huh.txt":          {Data: []byte("  3")},
+	}
+
+	fp.SetHeight(10)
+
+	cmd := fp.Init()
+	fp, _ = fp.Update(cmd())
+
+	lines := strings.Split(fp.View(), "\n")
+	for lines[len(lines)-1] == "" {
+		lines = lines[:len(lines)-1]
+	}
+	expected := []string{"bubbles", "charm.sh", "hello.txt", "huh.txt"}
+	if len(lines) != len(expected) {
+		t.Fatalf("len(lines) != len(expected): got %d, want %d", len(lines), len(expected))
+	}
+	for i, line := range lines {
+		contains := expected[i]
+		if got := line; !strings.Contains(got, contains) {
+			t.Errorf("View() line %d = %v; must contains %v", i, got, contains)
+		}
+	}
+
+	expected = []string{"0B", "4B", "2B", "3B"}
+	if len(lines) != len(expected) {
+		t.Fatalf("len(lines) != len(expected): got %d, want %d", len(lines), len(expected))
+	}
+	for i, line := range lines {
+		contains := expected[i]
+		if got := line; !strings.Contains(got, contains) {
+			t.Errorf("View() line %d = %v; must contains %v", i, got, contains)
+		}
+	}
+
+	fp, cmd = fp.Update(tea.KeyPressMsg{Code: tea.KeyRight})
+	fp, _ = fp.Update(cmd())
+
+	lines = strings.Split(fp.View(), "\n")
+	for lines[len(lines)-1] == "" {
+		lines = lines[:len(lines)-1]
+	}
+	expected = []string{"help.txt", "list.txt"}
+	if len(lines) != len(expected) {
+		t.Fatalf("len(lines) != len(expected): got %d, want %d", len(lines), len(expected))
+	}
+	for i, line := range lines {
+		contains := expected[i]
+		if got := line; !strings.Contains(got, contains) {
+			t.Errorf("View() line %d = %v; must contains %v", i, got, contains)
+		}
+	}
+}