should be it

external/duckdb/test/memoryleak/test_appender.cpp

@@ -0,0 +1,87 @@
+#include "catch.hpp"
+#include "test_helpers.hpp"
+#include "duckdb/main/config.hpp"
+#include "test_config.hpp"
+
+using namespace duckdb;
+using namespace std;
+
+void rand_str(char *dest, idx_t length) {
+	char charset[] = "0123456789"
+	                 "abcdefghijklmnopqrstuvwxyz"
+	                 "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
+
+	while (length-- > 0) {
+		idx_t index = (double)rand() / RAND_MAX * (sizeof charset - 1);
+		*dest++ = charset[index];
+	}
+	*dest = '\0';
+}
+
+TEST_CASE("Test repeated appending small chunks to a table", "[memoryleak]") {
+	if (!TestConfiguration::TestMemoryLeaks()) {
+		return;
+	}
+	duckdb_database db;
+	duckdb_connection con;
+	duckdb_state state;
+	auto db_path = TestCreatePath("appender_leak_test.db");
+	TestDeleteFile(db_path);
+
+	if (duckdb_open(db_path.c_str(), &db) == DuckDBError) {
+		// handle error
+		FAIL("Failed to open");
+	}
+	if (duckdb_connect(db, &con) == DuckDBError) {
+		// handle error
+		FAIL("Failed to connect");
+	}
+
+	state =
+	    duckdb_query(con, "create table test(col1 varchar, col2 varchar, col3 bigint, col4 bigint, col5 double)", NULL);
+	if (state == DuckDBError) {
+		FAIL("Failed to create table");
+	}
+	state = duckdb_query(con, "set memory_limit='100mb'", NULL);
+	if (state == DuckDBError) {
+		FAIL("Failed to set memory limit");
+	}
+
+	long n1 = 0;
+	double d1 = 0.5;
+	for (int i = 0; i < 100000; i++) {
+		duckdb_appender appender;
+		if (duckdb_appender_create(con, NULL, "test", &appender) == DuckDBError) {
+			FAIL("Failed to create appender");
+		}
+		for (int j = 0; j < 1000; j++) {
+			char str[41];
+			rand_str(str, sizeof(str) - 1);
+			duckdb_append_varchar(appender, str);
+			duckdb_append_varchar(appender, "hello");
+			duckdb_append_int64(appender, n1++);
+			duckdb_append_int64(appender, n1++);
+			duckdb_append_double(appender, d1);
+			d1 += 1.25;
+			duckdb_appender_end_row(appender);
+		}
+		state = duckdb_appender_close(appender);
+		if (state == DuckDBError) {
+			FAIL("Failed to close appender");
+		}
+		state = duckdb_appender_destroy(&appender);
+		if (state == DuckDBError) {
+			fprintf(stderr, "err: %d", state);
+			FAIL("Failed to destroy appender");
+		}
+		if (i % 500 == 0) {
+			printf("completed %d\n", i);
+			duckdb_query(con, "checkpoint", NULL);
+		}
+	}
+
+	// cleanup
+	duckdb_disconnect(&con);
+	duckdb_close(&db);
+	REQUIRE(1 == 1);
+}