From cefa730d3542867912f9b63cc63cbe6d4690ccd5 Mon Sep 17 00:00:00 2001
From: dreamcmi <1912544842@qq.com>
Date: Fri, 12 May 2023 00:24:40 +0800
Subject: [PATCH] Fixed a bug where help("modules") crashed when no lib was
 loaded

---
 src/PikaObj.c          |  4 ++++
 test/pikaMain-test.cpp | 16 ++++++++++++++++
 2 files changed, 20 insertions(+)

diff --git a/src/PikaObj.c b/src/PikaObj.c
index eb5dcf4ae..3482a24d2 100644
--- a/src/PikaObj.c
+++ b/src/PikaObj.c
@@ -2427,6 +2427,10 @@ PikaObj* obj_linkLibrary(PikaObj* self, uint8_t* library_bytes) {
 
 void obj_printModules(PikaObj* self) {
     LibObj* lib = obj_getObj(self, "@lib");
+    if (lib == NULL) {
+        pika_platform_printf("Error: Not found LibObj, please execute obj_linkLibrary()\r\n");
+        return;
+    }
     pika_platform_printf(arg_getStr((Arg*)g_PikaObjState.helpModulesCmodule));
     LibObj_printModules(lib);
 }
diff --git a/test/pikaMain-test.cpp b/test/pikaMain-test.cpp
index 2cd6865b6..abd5d4316 100644
--- a/test/pikaMain-test.cpp
+++ b/test/pikaMain-test.cpp
@@ -3054,4 +3054,20 @@ TEST(pikaMain, _obj_set_str_null) {
     EXPECT_EQ(pikaMemNow(), 0);
 }
 
+TEST(pikaMain, shell_nolib_print_help) {
+    char lines[] = {"help(\"modules\")\n"};
+    /* init */
+    g_PikaMemInfo.heapUsedMax = 0;
+    PikaObj* pikaMain = newRootObj("pikaMain", New_PikaMain);
+    /* run */
+    for (size_t i = 0; i < strGetSize(lines); i++) {
+        obj_runChar(pikaMain, lines[i]);
+    }
+    /* assert */
+    EXPECT_STREQ(log_buff[1], "Error: Not found LibObj, please execute obj_linkLibrary()\r\n");
+    /* deinit */
+    obj_deinit(pikaMain);
+    EXPECT_EQ(pikaMemNow(), 0);
+}
+
 TEST_END
\ No newline at end of file