From 7dd74799edeb396b8db117c0935c779129ef1715 Mon Sep 17 00:00:00 2001
From: connorwstein <connor.stein@mail.mcgill.ca>
Date: Thu, 15 Jan 2026 10:50:29 -0500
Subject: [PATCH] Prefix helper

---
 keystore/keystore.go               | 16 +++++++++++++-
 keystore/keystore_internal_test.go | 34 ++++++++++++++++++++++--------
 2 files changed, 40 insertions(+), 10 deletions(-)

diff --git a/keystore/keystore.go b/keystore/keystore.go
index 15306cda22..dce33c613f 100644
--- a/keystore/keystore.go
+++ b/keystore/keystore.go
@@ -35,6 +35,20 @@ func (k KeyPath) Base() string {
 	return k[len(k)-1]
 }
 
+// HasPrefix returns true if k starts with the given prefix path.
+// For example, KeyPath{"solana", "tx", "my-key"}.HasPrefix(KeyPath{"solana", "tx"}) returns true.
+func (k KeyPath) HasPrefix(prefix KeyPath) bool {
+	if len(prefix) > len(k) {
+		return false
+	}
+	for i := range prefix {
+		if k[i] != prefix[i] {
+			return false
+		}
+	}
+	return true
+}
+
 func NewKeyPath(segments ...string) KeyPath {
 	return segments
 }
@@ -44,7 +58,7 @@ func NewKeyPathFromString(fullName string) KeyPath {
 }
 
 // joinKeySegments joins path-like key name segments using "/" and avoids double slashes.
-// Empty segments are skipped so joinKeySegments("EVM", "TX", "my-key") => "EVM/TX/my-key".
+// Empty segments are skipped so joinKeySegments("evm", "tx", "my-key") => "evm/tx/my-key".
 func joinKeySegments(segments ...string) string {
 	cleaned := make([]string, 0, len(segments))
 	for _, s := range segments {
diff --git a/keystore/keystore_internal_test.go b/keystore/keystore_internal_test.go
index 515a3987a8..4418dd9b62 100644
--- a/keystore/keystore_internal_test.go
+++ b/keystore/keystore_internal_test.go
@@ -36,17 +36,33 @@ func TestJoinKeySegments(t *testing.T) {
 		segments []string
 		expected string
 	}{
-		{segments: []string{"EVM", "TX", "my-key"}, expected: "EVM/TX/my-key"},
-		{segments: []string{"EVM", "/TX", "my-key"}, expected: "EVM/TX/my-key"},
-		{segments: []string{"EVM", "TX/", "my-key"}, expected: "EVM/TX/my-key"},
-		{segments: []string{"EVM", "TX", "/my-key"}, expected: "EVM/TX/my-key"},
-		{segments: []string{"EVM", "TX", "my-key", ""}, expected: "EVM/TX/my-key"},
-		{segments: []string{"EVM", "TX", "my-key", "/"}, expected: "EVM/TX/my-key"},
-		{segments: []string{"EVM", "TX", "my-key", "//"}, expected: "EVM/TX/my-key"},
-		{segments: []string{"EVM", "TX", "my-key", "///"}, expected: "EVM/TX/my-key"},
-		{segments: []string{"EVM", "TX", "my-key", "////"}, expected: "EVM/TX/my-key"},
+		{segments: []string{"evm", "tx", "my-key"}, expected: "evm/tx/my-key"},
+		{segments: []string{"evm", "/tx", "my-key"}, expected: "evm/tx/my-key"},
+		{segments: []string{"evm", "tx/", "my-key"}, expected: "evm/tx/my-key"},
+		{segments: []string{"evm", "tx", "/my-key"}, expected: "evm/tx/my-key"},
+		{segments: []string{"evm", "tx", "my-key", ""}, expected: "evm/tx/my-key"},
+		{segments: []string{"evm", "tx", "my-key", "/"}, expected: "evm/tx/my-key"},
+		{segments: []string{"evm", "tx", "my-key", "//"}, expected: "evm/tx/my-key"},
+		{segments: []string{"evm", "tx", "my-key", "///"}, expected: "evm/tx/my-key"},
+		{segments: []string{"evm", "tx", "my-key", "////"}, expected: "evm/tx/my-key"},
 	}
 	for _, tt := range tests {
 		require.Equal(t, tt.expected, joinKeySegments(tt.segments...))
 	}
 }
+
+func TestKeyPathHasPrefix(t *testing.T) {
+	tests := []struct {
+		path     KeyPath
+		prefix   KeyPath
+		expected bool
+	}{
+		{path: KeyPath{"evm", "tx", "my-key"}, prefix: KeyPath{"evm", "tx"}, expected: true},
+		{path: KeyPath{"evm", "tx", "my-key"}, prefix: KeyPath{"evm"}, expected: true},
+		{path: KeyPath{"evm", "tx", "my-key"}, prefix: KeyPath{"evm", "tx", "my-key"}, expected: true},
+		{path: KeyPath{"evm", "tx", "my-key"}, prefix: KeyPath{"evm", "tx", "my-key", "extra"}, expected: false},
+	}
+	for _, tt := range tests {
+		require.Equal(t, tt.expected, tt.path.HasPrefix(tt.prefix))
+	}
+}