diff --git a/libexec/rbenv-rehash b/libexec/rbenv-rehash
index b05a4c76..8a6d66d6 100755
--- a/libexec/rbenv-rehash
+++ b/libexec/rbenv-rehash
@@ -17,7 +17,11 @@ mkdir -p "$SHIM_PATH"
 set -o noclobber
 { echo > "$PROTOTYPE_SHIM_PATH"
 } 2>/dev/null ||
-{ echo "rbenv: cannot rehash: $PROTOTYPE_SHIM_PATH exists"
+{ if [ -w "$SHIM_PATH" ]; then
+    echo "rbenv: cannot rehash: $PROTOTYPE_SHIM_PATH exists"
+  else
+    echo "rbenv: cannot rehash: $SHIM_PATH isn't writable"
+  fi
   exit 1
 } >&2
 set +o noclobber
diff --git a/test/rehash.bats b/test/rehash.bats
new file mode 100755
index 00000000..22f26d07
--- /dev/null
+++ b/test/rehash.bats
@@ -0,0 +1,33 @@
+#!/usr/bin/env bats
+
+export PATH="${BATS_TEST_DIRNAME}/../libexec:$PATH"
+
+RBENV_TEST_ROOT="${BATS_TMPDIR}/rbenv"
+export RBENV_ROOT="$RBENV_TEST_ROOT"
+
+teardown() {
+  rm -rf "$RBENV_TEST_ROOT"
+}
+
+@test "empty rehash" {
+  run rbenv-rehash
+  [ "$status" -eq 0 ]
+  [ -d "${RBENV_TEST_ROOT}/shims" ]
+  rmdir "${RBENV_TEST_ROOT}/shims"
+}
+
+@test "shims directory not writable" {
+  mkdir -p "${RBENV_TEST_ROOT}/shims"
+  chmod -w "${RBENV_TEST_ROOT}/shims"
+  run rbenv-rehash
+  [ "$status" -eq 1 ]
+  [ "$output" = "rbenv: cannot rehash: ${RBENV_TEST_ROOT}/shims isn't writable" ]
+}
+
+@test "rehash in progress" {
+  mkdir -p "${RBENV_TEST_ROOT}/shims"
+  touch "${RBENV_TEST_ROOT}/shims/.rbenv-shim"
+  run rbenv-rehash
+  [ "$status" -eq 1 ]
+  [ "$output" = "rbenv: cannot rehash: ${RBENV_TEST_ROOT}/shims/.rbenv-shim exists" ]
+}