From 4531aebd291186e9dd49fb2ec1f1b9b96a4ed23f Mon Sep 17 00:00:00 2001 From: James Booth Date: Mon, 30 Apr 2012 19:52:56 +0100 Subject: [PATCH] More work on history --- prof_history.c | 107 +++++++++++++++++++++++++++++++------------- test_prof_history.c | 37 ++++++++++++--- 2 files changed, 107 insertions(+), 37 deletions(-) diff --git a/prof_history.c b/prof_history.c index 24213140..e896ac15 100644 --- a/prof_history.c +++ b/prof_history.c @@ -32,17 +32,26 @@ PHistory p_history_new(unsigned int size) void p_history_append(PHistory history, char *item) { - char *copied = strdup(item); + char *copied = ""; + if (item != NULL) { + copied = strdup(item); + } - // if not editing history (no session) + // if no history yet, just add the item + if (history->items == NULL) { + history->items = g_list_append(history->items, copied); + return; + } + + // if not editing history (no session started) if (history->session == NULL) { - // if already at max size + // lose first element if hit max size if (g_list_length(history->items) == history->max_size) { // remove first element GList *first = g_list_first(history->items); - const char *first_item = (char *) first->data; + char *first_item = first->data; history->items = g_list_remove(history->items, first_item); } @@ -51,19 +60,23 @@ void p_history_append(PHistory history, char *item) // if editing history (session exists with possible changes) } else { - - // if adding a new element, copy the session over the history - if (history->sess_curr == history->sess_new) { + + // if adding a new item, copy the session over the history + if ((history->sess_new != NULL) && + (history->sess_curr == history->sess_new)) { _replace_history_with_session(history); // otherwise, adding edited history item } else { - // remove the new item, from the session - history->session = g_list_reverse(history->session); - GList *first = g_list_first(history->session); - const char *first_item = (char *) first->data; - history->session = g_list_remove(history->session, first_item); - history->session = g_list_reverse(history->session); + + // discard the new item if there was one + if (history->sess_new != NULL) { + history->session = g_list_reverse(history->session); + GList *first = g_list_first(history->session); + char *first_item = first->data; + history->session = g_list_remove(history->session, first_item); + history->session = g_list_reverse(history->session); + } // copy sess_curr to the end of the session char *new_data = strdup(history->sess_curr->data); @@ -99,45 +112,77 @@ static void _replace_history_with_session(PHistory history) char * p_history_previous(PHistory history, char *item) { + // no history if (history->items == NULL) { return item; } + char *copied = ""; + if (item != NULL) { + copied = strdup(item); + } + + // no session, create one if (history->session == NULL) { history->session = g_list_copy(history->items); history->sess_curr = g_list_last(history->session); + history->items_curr = g_list_last(history->items); + + // add the new item including empty string + g_list_append(history->session, copied); + history->sess_new = g_list_last(history->session); + + char *result = strdup(history->sess_curr->data); + return result; + + // session exists } else { + // update the currently pointed to item with passed data + history->sess_curr->data = copied; + + // move to previous history->sess_curr = g_list_previous(history->sess_curr); + history->items_curr = g_list_previous(history->items_curr); + + // set to first if rolled over beginning + if (history->sess_curr == NULL) { + history->sess_curr = g_list_first(history->session); + history->items_curr = g_list_first(history->items); + } } - // set to first if rolled over beginning - if (history->sess_curr == NULL) { - history->sess_curr = g_list_first(history->session); - } - - char *curr = history->sess_curr->data; - char *result = malloc((strlen(curr) + 1) * sizeof(char)); - strcpy(result, curr); - + char *result = strdup(history->sess_curr->data); return result; } char * p_history_next(PHistory history, char *item) { - if (history->session == NULL) { - return NULL; - } else { - history->sess_curr = g_list_next(history->sess_curr); + + // no history, or no session, return item + if ((history->items == NULL) || (history->session == NULL)) { + return item; } - // set to last if rolled over end + char *copied = ""; + if (item != NULL) { + copied = strdup(item); + } + + // session exists + + // update the currently pointed to item with passed data + history->sess_curr->data = copied; + + // move to next + history->sess_curr = g_list_next(history->sess_curr); + history->items_curr = g_list_next(history->items_curr); + + // set to last if rolled over beginning if (history->sess_curr == NULL) { history->sess_curr = g_list_last(history->session); + history->items_curr = NULL; } - char *curr = history->sess_curr->data; - char *result = malloc((strlen(curr) + 1) * sizeof(char)); - strcpy(result, curr); - + char *result = strdup(history->sess_curr->data); return result; } diff --git a/test_prof_history.c b/test_prof_history.c index db4ef24b..6b42a160 100644 --- a/test_prof_history.c +++ b/test_prof_history.c @@ -10,12 +10,12 @@ void previous_on_empty_returns_current(void) assert_string_equals("inp", item); } -void next_on_empty_returns_null(void) +void next_on_empty_returns_current(void) { PHistory history = p_history_new(10); char *item = p_history_next(history, "inp"); - assert_is_null(item); + assert_string_equals("inp", item); } void previous_once_returns_last(void) @@ -71,7 +71,7 @@ void previous_goes_to_correct_element(void) assert_string_equals("going", item3); } -void prev_then_next_returns_null(void) +void prev_then_next_returns_empty(void) { PHistory history = p_history_new(10); p_history_append(history, "Hello"); @@ -79,17 +79,42 @@ void prev_then_next_returns_null(void) char *item1 = p_history_previous(history, NULL); char *item2 = p_history_next(history, item1); - assert_is_null(item2); + assert_string_equals("", item2); +} + +void prev_with_val_then_next_returns_val(void) +{ + PHistory history = p_history_new(10); + p_history_append(history, "Hello"); + + char *item1 = p_history_previous(history, "Oioi"); + char *item2 = p_history_next(history, item1); + + assert_string_equals("Oioi", item2); +} + +void prev_with_val_then_next_twice_returns_val(void) +{ + PHistory history = p_history_new(10); + p_history_append(history, "Hello"); + + char *item1 = p_history_previous(history, "Oioi"); + char *item2 = p_history_next(history, item1); + char *item3 = p_history_next(history, item2); + + assert_string_equals("Oioi", item3); } void register_prof_history_tests(void) { TEST_MODULE("prof_history tests"); TEST(previous_on_empty_returns_current); - TEST(next_on_empty_returns_null); + TEST(next_on_empty_returns_current); TEST(previous_once_returns_last); TEST(previous_twice_when_one_returns_first); TEST(previous_always_stops_at_first); TEST(previous_goes_to_correct_element); - TEST(prev_then_next_returns_null); + TEST(prev_then_next_returns_empty); + TEST(prev_with_val_then_next_returns_val); + TEST(prev_with_val_then_next_twice_returns_val); }