feat: add file history (closes #97)

history.go

@@ -0,0 +1,67 @@
+package main
+
+import (
+	"errors"
+	"io/fs"
+	"os"
+	"strings"
+)
+
+type fileHistory struct {
+	items []string
+	f *os.File
+}
+
+func newFileHistory() (*fileHistory, error) {
+	data, err := os.ReadFile(defaultHistPath)
+	if err != nil {
+		if !errors.Is(err, fs.ErrNotExist) {
+			return nil, err
+		}
+	}
+	
+	var itms []string
+	for _, l := range strings.Split(string(data), "\n") {
+		itms = append(itms, l)
+	}
+	f, err := os.OpenFile(defaultHistPath, os.O_RDWR | os.O_CREATE, 0755)
+	if err != nil {
+		return nil, err
+	}
+	
+	fh := &fileHistory{
+		items: itms,
+		f: f,
+	}
+	
+	return fh, nil
+}
+
+func (h *fileHistory) Write(line string) (int, error) {
+	_, err := h.f.WriteString(line + "\n")
+	if err != nil {
+		return 0, err
+	}
+	h.f.Sync()
+	
+	h.items = append(h.items, line)
+	return len(h.items), nil
+}
+
+func (h *fileHistory) GetLine(idx int) (string, error) {
+	if len(h.items) == 0 {
+		return "", nil
+	}
+	if idx == -1 { // this should be fixed readline side
+		return "", nil
+	}
+	return h.items[idx], nil
+}
+
+func (h *fileHistory) Len() int {
+	return len(h.items)
+}
+
+func (h *fileHistory) Dump() interface{} {
+	return nil
+}

rl.go

@@ -18,6 +18,11 @@ type lineReader struct {
 // other gophers might hate this naming but this is local, shut up
 func newLineReader(prompt string) *lineReader {
 	rl := readline.NewInstance()
+	fileHist, err := newFileHistory()
+	if err != nil {
+		panic(err)
+	}
+	rl.SetHistoryCtrlR("file", fileHist)
 	rl.ShowVimMode = false
 	rl.ViModeCallback = func(mode readline.ViMode) {
 		modeStr := ""