Match the prompt more fuzzily

main.go

@@ -148,8 +148,7 @@ func main() {
 				prompt = nextPrompt
 				filteredKeys = []string{}
 				for _, k := range keys {
-					// TODO: Match more fuzzily
-					if strings.Contains(k, prompt) {
+					if matchesPrompt(prompt, k) {
 						filteredKeys = append(filteredKeys, k)
 					}
 				}
@@ -430,3 +429,19 @@ func drawPrompt(s tcell.Screen, height int, prompt string) {
 func drawLoadingScreen(s tcell.Screen, height int) {
 	drawLine(s, 2, height-2, tcell.StyleDefault.Foreground(tcell.ColorYellow), "Loading...")
 }
+
+func matchesPrompt(prompt, s string) bool {
+	if len(prompt) == 0 {
+		return true
+	}
+	index := 0
+	for _, c := range []byte(s) {
+		if c == prompt[index] {
+			if index == len(prompt)-1 {
+				return true
+			}
+			index++
+		}
+	}
+	return false
+}

main_test.go

@@ -85,6 +85,56 @@ func TestGetSecret(t *testing.T) {
 	}
 }
 
+func TestMatchesPrompt(t *testing.T) {
+	tests := map[string]struct {
+		prompt   string
+		key      string
+		expected bool
+	}{
+		"match": {
+			prompt:   "set",
+			key:      "secret",
+			expected: true,
+		},
+		"match2": {
+			prompt:   "seet",
+			key:      "secret",
+			expected: true,
+		},
+		"exact-match": {
+			prompt:   "secret",
+			key:      "secret",
+			expected: true,
+		},
+		"no-match": {
+			prompt:   "asdf",
+			key:      "secret",
+			expected: false,
+		},
+		"no-match1": {
+			prompt:   "a",
+			key:      "secret",
+			expected: false,
+		},
+		"no-match2": {
+			prompt:   "seeet",
+			key:      "secret",
+			expected: false,
+		},
+	}
+	for name, test := range tests {
+		t.Run(name, func(t *testing.T) {
+			if matchesPrompt(test.prompt, test.key) != test.expected {
+				if test.expected {
+					t.Fatalf("Expected %s to match %s", test.prompt, test.key)
+				} else {
+					t.Fatalf("Expected %s to not match %s", test.prompt, test.key)
+				}
+			}
+		})
+	}
+}
+
 func startVault(token, addr string) (*exec.Cmd, error) {
 	cmd := exec.Command("vault", "server", "-dev", "-dev-root-token-id", token, "-address", addr)
 	if err := cmd.Start(); err != nil {