Handle the case where start is greater than end in list.index() (lc…

…ompilers#2022)

src/libasr/codegen/llvm_utils.cpp

@@ -2787,7 +2787,10 @@ namespace LCompilers {
 
         llvm::Value* cond = builder->CreateICmpEQ(
                               LLVM::CreateLoad(*builder, i), end_point);
-        llvm_utils->create_if_else(cond, [&]() {
+        llvm::Value* start_greater_than_end = builder->CreateICmpSGE(
+                                                LLVM::CreateLoad(*builder, i), end_point);
+        llvm::Value* condition = builder->CreateOr(cond, start_greater_than_end);
+        llvm_utils->create_if_else(condition, [&]() {
             std::string message = "The list does not contain the element: ";
             llvm::Value *fmt_ptr = builder->CreateGlobalStringPtr("ValueError: %s%d\n");
             llvm::Value *fmt_ptr2 = builder->CreateGlobalStringPtr(message);

tests/errors/test_list_index4.py

@@ -0,0 +1,8 @@
+from lpython import i32
+
+def test_list_index4_error():
+    a: list[i32]
+    a = [1, 2, 3]
+    print(a.index(2,2,1))
+
+test_list_index4_error()

tests/reference/runtime-test_list_index4-c31dfdb.json

@@ -0,0 +1,13 @@
+{
+    "basename": "runtime-test_list_index4-c31dfdb",
+    "cmd": "lpython {infile}",
+    "infile": "tests/errors/test_list_index4.py",
+    "infile_hash": "4513031129335b8c83686936c12f6b24516c14a79ad5c3b9a9d98113",
+    "outfile": null,
+    "outfile_hash": null,
+    "stdout": null,
+    "stdout_hash": null,
+    "stderr": "runtime-test_list_index4-c31dfdb.stderr",
+    "stderr_hash": "3e3eee1ba7f96c1edaeed1c7b93f54b397dbe3b08d20c9b720c291a5",
+    "returncode": 1
+}

tests/reference/runtime-test_list_index4-c31dfdb.stderr

@@ -0,0 +1 @@
+ValueError: The list does not contain the element: 2

tests/tests.toml

@@ -789,6 +789,10 @@ run = true
 filename = "errors/test_list_index3.py"
 run = true
 
+[[test]]
+filename = "errors/test_list_index4.py"
+run = true
+
 [[test]]
 filename = "errors/test_list1.py"
 asr = true