Fix buffer list not having stable ptrs

Was caused by using a vector that used realloc to grow. That only works
sometimes. Now instead, the buffer list is a chunked linked list, i.e. a
linked list where each element is a fixed size array.

1 files changed, 135 insertions, 0 deletions

diff --git a/test/buflist.c b/test/buflist.c
new file mode 100644
index 0000000..b0bc241
--- /dev/null
+++ b/test/buflist.c
@@ -0,0 +1,135 @@
+#include "assert.h"
+#include "test.h"
+
+#include "dged/buffer.h"
+#include "dged/buffers.h"
+
+struct hook_call_args {
+  struct buffer *buffer[64];
+  size_t call_count;
+};
+
+static void add_remove_hook(struct buffer *buffer, void *userdata) {
+  struct hook_call_args *args = (struct hook_call_args *)userdata;
+
+  if (args->call_count < 64) {
+    args->buffer[args->call_count] = buffer;
+  }
+
+  ++args->call_count;
+}
+
+static void add(void) {
+  struct buffers buflist;
+  buffers_init(&buflist, 16);
+
+  ASSERT(buffers_num_buffers(&buflist) == 0,
+         "Expected buffer list to be empty upon creation.");
+
+  struct buffer b1 = buffer_create("b1");
+  struct buffer b2 = buffer_create("b2");
+
+  struct hook_call_args hook_args = {0};
+  buffers_add_add_hook(&buflist, add_remove_hook, &hook_args);
+
+  struct buffer *bp1 = buffers_add(&buflist, b1);
+  struct buffer *bp2 = buffers_add(&buflist, b2);
+
+  ASSERT(hook_args.call_count == 2,
+         "Expected add hook to be called two times when adding two buffers.");
+  ASSERT(hook_args.buffer[0] == bp1,
+         "Expected add hook to be called with first buffer first.");
+  ASSERT(hook_args.buffer[1] == bp2,
+         "Expected add hook to be called with second buffer second.");
+
+  buffers_destroy(&buflist);
+}
+
+static void find(void) {
+  struct buffers buflist;
+  buffers_init(&buflist, 16);
+
+  struct buffer b1 = buffer_create("b1");
+  struct buffer b2 = buffer_create("b2");
+  struct buffer b3 = buffer_create("b3");
+  buffer_set_filename(&b3, "b3.txt");
+
+  struct buffer *bp1 = buffers_add(&buflist, b1);
+  struct buffer *bp2 = buffers_add(&buflist, b2);
+  struct buffer *bp3 = buffers_add(&buflist, b3);
+
+  struct buffer *found1 = buffers_find(&buflist, "b1");
+  ASSERT(found1 == bp1, "Expected to find equally named buffer");
+
+  struct buffer *found2 = buffers_find(&buflist, "b2");
+  ASSERT(found2 == bp2, "Expected to find equally named buffer");
+
+  struct buffer *ne = buffers_find(&buflist, "nonsense");
+  ASSERT(ne == NULL, "Expected to not find non-existent buffer");
+
+  struct buffer *found3 = buffers_find_by_filename(&buflist, "b3.txt");
+  ASSERT(found3 == bp3,
+         "Expected to be able to find buffer 3 by filename since it has one.");
+
+  buffers_destroy(&buflist);
+}
+
+static void remove_buffer() {
+  struct buffers buflist;
+  buffers_init(&buflist, 16);
+
+  struct buffer b1 = buffer_create("b1");
+  struct buffer b2 = buffer_create("b2");
+
+  buffers_add(&buflist, b1);
+  struct buffer *bp2 = buffers_add(&buflist, b2);
+
+  struct hook_call_args hook_args = {0};
+  buffers_add_remove_hook(&buflist, add_remove_hook, &hook_args);
+
+  bool removed = buffers_remove(&buflist, "b2");
+  ASSERT(removed, "Expected existing buffer to have been removed");
+  struct buffer *ne = buffers_find(&buflist, "b2");
+  ASSERT(ne == NULL, "Expected to not find buffer after removal");
+  ASSERT(buffers_num_buffers(&buflist) == 1,
+         "Expected number of buffers to be 1 after removal.");
+
+  ASSERT(hook_args.call_count == 1, "Expected remove hook to be called once.");
+  ASSERT(
+      hook_args.buffer[0] == bp2,
+      "Expected remove hook to be called with the removed buffer as argument.");
+
+  buffers_destroy(&buflist);
+}
+
+static void grow_list() {
+  struct buffers buflist;
+  buffers_init(&buflist, 2);
+
+  struct buffer b1 = buffer_create("b1");
+  struct buffer b2 = buffer_create("b2");
+  struct buffer b3 = buffer_create("b3");
+  struct buffer b4 = buffer_create("b4");
+
+  struct buffer *bp1 = buffers_add(&buflist, b1);
+  buffers_add(&buflist, b2);
+  buffers_add(&buflist, b3);
+  struct buffer *bp4 = buffers_add(&buflist, b4);
+  ASSERT(buffers_num_buffers(&buflist) == 4,
+         "Expected buffer count to be 4 after adding 4 buffers.");
+
+  struct buffer *found = buffers_find(&buflist, "b1");
+  ASSERT(found == bp1, "Expected pointer to remain stable after resize.");
+
+  found = buffers_find(&buflist, "b4");
+  ASSERT(found == bp4, "Expected to be able to find last added buffer.");
+
+  buffers_destroy(&buflist);
+}
+
+void run_buflist_tests(void) {
+  run_test(add);
+  run_test(find);
+  run_test(remove_buffer);
+  run_test(grow_list);
+}