diff --git a/src/acrostic-generator-tests.c b/src/acrostic-generator-tests.c
index 071f16a928c5f262019ed8c9a0993f4faa33e8fe..25659cee8b4e337dd9e63af65a36d0d65e78cb61 100644
--- a/src/acrostic-generator-tests.c
+++ b/src/acrostic-generator-tests.c
@@ -61,7 +61,7 @@ test_acrostic_set_text (void)
 
   g_assert_true (acrostic_generator_set_text (generator, "CARNEGIEVISITEDPRINCETONANDTOLDWILSONWHATHISYOUNGMENNEEDEDWASNOTALAWSCHOOLBUTALAKETOROWONINADDITIONTOBEINGASPORTTHATBUILTCHARACTERANDWOULDLETTHEUNDERGRADUATESRELAXROWINGWOULDKEEPTHEMFROMPLAYINGFOOTBALLAROUGHNECKSPORTCARNEGIEDETESTED", "DAVIDHALBERSTAMTHEAMATEURS", &error));
 
-  g_assert_true (!acrostic_generator_set_text (generator, "CARNEGIEISITEDPRINCETONANDTOLDWILSONWHATHISYOUNGMENNEEDEDWASNOTALAWSCHOOLBUTALAKETOROWONINADDITIONTOBEINGASPORTTHATBUILTCHARACTERANDWOULDLETTHEUNDERGRADUATESRELAXROWINGWOULDKEEPTHEMFROMPLAYINGFOOTBALLAROUGHNECKSPORTCARNEGIEDETESTED", "DAVIDHALBERSTAMTHEAMATEURS", &error));
+  g_assert_false (acrostic_generator_set_text (generator, "CARNEGIEISITEDPRINCETONANDTOLDWILSONWHATHISYOUNGMENNEEDEDWASNOTALAWSCHOOLBUTALAKETOROWONINADDITIONTOBEINGASPORTTHATBUILTCHARACTERANDWOULDLETTHEUNDERGRADUATESRELAXROWINGWOULDKEEPTHEMFROMPLAYINGFOOTBALLAROUGHNECKSPORTCARNEGIEDETESTED", "DAVIDHALBERSTAMTHEAMATEURS", &error));
 }
 
 #if 0
@@ -103,11 +103,11 @@ test_acrostic_error (void)
 
   generator = create_test_generator ();
 
-  g_assert_true (!acrostic_generator_set_text (generator, "LIFE IS TOO SHORT", "TOLSTOI", &error));
-  g_assert_true (g_error_matches (error, ACROSTIC_GENERATOR_ERROR, ACROSTIC_GENERATOR_ERROR_SOURCE_TOO_SHORT));
+  g_assert_false (acrostic_generator_set_text (generator, "LIFE IS TOO SHORT", "TOLSTOI", &error));
+  g_assert_error (error, ACROSTIC_GENERATOR_ERROR, ACROSTIC_GENERATOR_ERROR_SOURCE_TOO_SHORT);
 
-  g_assert_true (!acrostic_generator_set_text (generator, "CARNEGIEISITEDPRINCETONANDTOLDWILSONWHATHISYOUNGMENNEEDEDWASNOTALAWSCHOOLBUTALAKETOROWONINADDITIONTOBEINGASPORTTHATBUILTCHARACTERANDWOULDLETTHEUNDERGRADUATESRELAXROWINGWOULDKEEPTHEMFROMPLAYINGFOOTBALLAROUGHNECKSPORTCARNEGIEDETESTED", "DAVIDHALBERSTAMTHEAMATEURS", &error));
-  g_assert_true (g_error_matches (error, ACROSTIC_GENERATOR_ERROR, ACROSTIC_GENERATOR_ERROR_SOURCE_NOT_IN_QUOTE));
+  g_assert_false (acrostic_generator_set_text (generator, "CARNEGIEISITEDPRINCETONANDTOLDWILSONWHATHISYOUNGMENNEEDEDWASNOTALAWSCHOOLBUTALAKETOROWONINADDITIONTOBEINGASPORTTHATBUILTCHARACTERANDWOULDLETTHEUNDERGRADUATESRELAXROWINGWOULDKEEPTHEMFROMPLAYINGFOOTBALLAROUGHNECKSPORTCARNEGIEDETESTED", "DAVIDHALBERSTAMTHEAMATEURS", &error));
+  g_assert_error (error, ACROSTIC_GENERATOR_ERROR, ACROSTIC_GENERATOR_ERROR_SOURCE_NOT_IN_QUOTE);
 }
 #endif
 
diff --git a/src/test-utils.c b/src/test-utils.c
index 56036a7a07b78df2a0403fd820b85dae75bcdb9f..d55632920eb923919dfcc5603d1a88d0814fa997 100644
--- a/src/test-utils.c
+++ b/src/test-utils.c
@@ -28,10 +28,10 @@ load_state (const char *filename, GridStateMode mode)
   GridState *state;
 
   g_assert_no_error (error);
-  g_assert (IPUZ_IS_CROSSWORD (puzzle));
+  g_assert_true (IPUZ_IS_CROSSWORD (puzzle));
 
   state = grid_state_new (IPUZ_CROSSWORD (puzzle), NULL, mode);
-  g_assert (state != NULL);
+  g_assert_nonnull (state);
 
   g_object_unref (puzzle);
   g_free (path);
@@ -48,10 +48,10 @@ load_state_with_quirks (const char *filename, GridStateMode mode)
   GridState *state;
 
   g_assert_no_error (error);
-  g_assert (IPUZ_IS_CROSSWORD (puzzle));
+  g_assert_true (IPUZ_IS_CROSSWORD (puzzle));
 
   state = grid_state_new (IPUZ_CROSSWORD (puzzle), NULL, mode);
-  g_assert (state != NULL);
+  g_assert_nonnull (state);
 
   state->quirks = crosswords_quirks_test_new (puzzle);
   /* Set some default values for the quirks to give us predictable results */
diff --git a/src/tests-main.c b/src/tests-main.c
index 595cbfbfb6b2a3ee9755ebac0ca37fe37b8a556b..712e55bb4ba0f4c6f2868137b11ea47e1e81b703 100644
--- a/src/tests-main.c
+++ b/src/tests-main.c
@@ -110,7 +110,7 @@ assert_cell_is_not_selectable (GridState *state, guint row, guint column, IpuzCe
 
   /* Check the cell type */
   cell = ipuz_grid_get_cell (IPUZ_GRID (state->xword), &coord);
-  g_assert (cell != NULL);
+  g_assert_nonnull (cell);
   g_assert_cmpint (ipuz_cell_get_cell_type (cell), ==, cell_type);
 
   /* And it must not be selectable, and the state must remain unchanged */
@@ -248,7 +248,7 @@ assert_next_prev_empty_cell_dir (GridState        **state,
 
       i_clue = g_array_index (clues, IpuzClue *, clue_index);
       ipuz_clues_get_id_by_clue (IPUZ_CLUES ((*state)->xword), i_clue, &i_clue_id);
-      g_assert (ipuz_clue_get_first_coord (i_clue, &i_clue_coord));
+      g_assert_true (ipuz_clue_get_first_coord (i_clue, &i_clue_coord));
       assert_state (*state, TRUE, i_clue_coord.row, i_clue_coord.column, i_clue_id.direction, i_clue_id.index);
 
       *state = grid_state_replace (*state, grid_state_do_command (*state, cmd));
diff --git a/src/word-list-tests.c b/src/word-list-tests.c
index 194da9e586a274d5a913af3d2ec3338050a1a02f..42e8a10717c79b27d630cbeb84848395387b667b 100644
--- a/src/word-list-tests.c
+++ b/src/word-list-tests.c
@@ -261,15 +261,15 @@ anagram_test (void)
   WordList *wl = get_test_word_list ();
 
   word_list_set_filter (wl, "CAT", WORD_LIST_ANAGRAM);
-  g_assert_true (word_list_get_n_items (wl) == 4);
+  g_assert_cmpuint (word_list_get_n_items (wl), ==, 4);
 
-  g_assert_true (!g_strcmp0 (word_list_get_word (wl, 0), "ACT"));
-  g_assert_true (!g_strcmp0 (word_list_get_word (wl, 1), "CAT"));
-  g_assert_true (!g_strcmp0 (word_list_get_word (wl, 2), "CTA"));
-  g_assert_true (!g_strcmp0 (word_list_get_word (wl, 3), "TAC"));
+  g_assert_cmpstr (word_list_get_word (wl, 0), ==, "ACT");
+  g_assert_cmpstr (word_list_get_word (wl, 1), ==, "CAT");
+  g_assert_cmpstr (word_list_get_word (wl, 2), ==, "CTA");
+  g_assert_cmpstr (word_list_get_word (wl, 3), ==, "TAC");
 
   word_list_set_filter (wl, "NOTANANAGRAM", WORD_LIST_ANAGRAM);
-  g_assert_true (word_list_get_n_items (wl) == 0);
+  g_assert_cmpuint (word_list_get_n_items (wl), ==, 0);
 
   g_object_unref (wl);
 }
@@ -423,17 +423,17 @@ frequency_test (void)
   /* Make sure the first character loads and is what we expect */
   c = g_utf8_get_char ("A");
   frequency = word_list_get_char_frequency (wl, 2, 0, c);
-  g_assert_true (ABS (frequency - 0.0909) < EPSILON);
+  g_assert_cmpfloat_with_epsilon (frequency, 0.0909, EPSILON);
 
   /* This should be 0 */
   c = g_utf8_get_char ("C");
   frequency = word_list_get_char_frequency (wl, 2, 0, c);
-  g_assert_true (ABS (frequency - 0.0f) < EPSILON);
+  g_assert_cmpfloat_with_epsilon (frequency, 0.0f, EPSILON);
 
   /* Make sure we can read from the end of the list.  */
   c = g_utf8_get_char ("Z");
   frequency = word_list_get_char_frequency (wl, 21, 20, c);
-  g_assert_true (ABS (frequency - 0.0f) < EPSILON);
+  g_assert_cmpfloat_with_epsilon (frequency, 0.0f, EPSILON);
 
   g_object_unref (wl);
 }