[gegl/wip/Jehan/gegl_node_process_success: 109/110] tests: improve unit tests for testing gegl_node_process_success().

[Øyvind "pippin" Kolås <ok src gnome org>]

commit 609fa040dc4752c84172c248236a5c16b085cd70
Author: Jehan <jehan girinstud io>
Date:   Wed Mar 27 11:45:17 2019 +0100

    tests: improve unit tests for testing gegl_node_process_success().
    
    load_denied() and save_denied() both failed on the CI infra. Instead of
    having a "permission denied" error, we got an empty file error, which
    means the test code was able to read the file. So the chmod must have
    failed (probably system restrictions on the build environment).
    So I transform the load_denied() to load_incomplete() with another type
    of error and I skip the save_denied() if g_chmod() fails and if testing
    access() afterwards still shows write access.

 tests/simple/test-errors.c | 171 +++++++++++++++++++++++----------------------
 1 file changed, 88 insertions(+), 83 deletions(-)
---
diff --git a/tests/simple/test-errors.c b/tests/simple/test-errors.c
index 05a2bf4c4..dbbc2981f 100644
--- a/tests/simple/test-errors.c
+++ b/tests/simple/test-errors.c
@@ -24,14 +24,21 @@
 
 #define SUCCESS  0
 #define FAILURE -1
+#define SKIP     77
 
 #define RUN_TEST(test_name) \
 { \
-  if (test_name()) \
+  gint retval = test_name (); \
+  if (retval == SUCCESS) \
     { \
       printf ("" #test_name " ... PASS\n"); \
       tests_passed++; \
     } \
+  else if (retval == SKIP) \
+    { \
+      printf ("" #test_name " ... SKIP\n"); \
+      tests_skipped++; \
+    } \
   else \
     { \
       printf ("" #test_name " ... FAIL\n"); \
@@ -40,12 +47,26 @@
   tests_run++; \
 }
 
-static gboolean save_denied    (void);
-static gboolean load_denied    (void);
-static gboolean load_zero_blit (void);
+#define MORE_INFO(expected_message, expected_domain, expected_code) \
+  if (status != SUCCESS) \
+    { \
+      fprintf (stderr, \
+               "- %s: Expected error (domain: %d - code: %d): %s\n", \
+               G_STRFUNC, expected_domain, expected_code, expected_message); \
+      if (error) \
+        fprintf (stderr, "- %s: Actual error (domain: %d - code: %d): %s\n", \
+                 G_STRFUNC, error->domain, error->code, error->message); \
+      else \
+        fprintf (stderr, "- %s: No error message!\n", G_STRFUNC); \
+    }
+
+static gboolean save_denied      (void);
+static gboolean load_incomplete  (void);
+static gboolean load_zero_blit   (void);
+static gboolean save_invalid_mp4 (void);
 
 /* Trying to save in a non-writable file with gegl_node_process(). */
-static gboolean
+static gint
 save_denied (void)
 {
   GeglNode  *graph;
@@ -53,9 +74,9 @@ save_denied (void)
   GeglNode  *crop;
   GeglNode  *save;
   GeglColor *red;
-  GError    *error   = NULL;
+  GError    *error  = NULL;
   gchar     *path;
-  gboolean   success = FALSE;
+  gint       status = FAILURE;
   gint       fd;
 
   red = gegl_color_new ("rgb(1.0, 0.0, 0.0)");
@@ -63,7 +84,14 @@ save_denied (void)
   /* Create a new empty file and forbid writing. */
   fd = g_file_open_tmp (NULL, &path, NULL);
   close (fd);
-  g_chmod (path, S_IRUSR);
+  if (g_chmod (path, S_IRUSR) == -1)
+    /* We cannot change file permission, thus the test cannot be done. */
+    return SKIP;
+  if (g_access (path, W_OK) == 0)
+    /* It seems even if the chmod succeeds, on some systems, we may still have
+     * write access. Check and skip if we do.
+     */
+    return SKIP;
 
   /* Try to save. */
   graph = gegl_node_new ();
@@ -85,14 +113,15 @@ save_denied (void)
   gegl_node_process (save);
   if (! gegl_node_process_success (save, &error))
     {
-      /* Expected error is "Error opening file “/tmp/.ZBD4YZ”: Permission denied"
-       * We test against error domain and code programmatically (no i18n
-       * issue, or string change problems, etc.
+      /* We test against error domain and code programmatically (no i18n
+       * issue, string change problems, etc.).
        */
-      success = (error                       &&
-                 error->domain == G_IO_ERROR &&
-                 error->code == G_IO_ERROR_PERMISSION_DENIED);
+      if (error                       &&
+          error->domain == G_IO_ERROR &&
+          error->code == G_IO_ERROR_PERMISSION_DENIED)
+        status = SUCCESS;
     }
+  MORE_INFO ("Error opening file “/some/tmp/path”: Permission denied", G_IO_ERROR, 
G_IO_ERROR_PERMISSION_DENIED);
 
   g_object_unref (graph);
   g_clear_error (&error);
@@ -101,28 +130,28 @@ save_denied (void)
   g_unlink (path);
   g_free (path);
 
-  return success;
+  return status;
 }
 
 /* Trying to load a non-readable file with gegl_node_process(). */
-static gboolean
-load_denied (void)
+static gint
+load_incomplete (void)
 {
   GeglNode   *graph;
   GeglNode   *source;
   GeglNode   *sink;
-  GeglBuffer *buffer  = NULL;
-  GError     *error   = NULL;
+  GeglBuffer *buffer = NULL;
+  GError     *error  = NULL;
   gchar      *path;
-  gboolean    success = FALSE;
+  gint        status = FAILURE;
   gint        fd;
 
-  /* Create a new empty file. It is not a valid image but we don't care as we
-   * are going to make it non-readable anyway.
+  /* Create a file with only the PNG header.
+   * It is not a valid PNG image.
    */
   fd = g_file_open_tmp (NULL, &path, NULL);
+  write (fd, "\x89\x50\x4e\x47\xd\xa\x1a\xa", 8);
   close (fd);
-  g_chmod (path, 0);
 
   /* Try to load it in a buffer. */
   graph = gegl_node_new ();
@@ -139,22 +168,13 @@ load_denied (void)
   gegl_node_process (sink);
   if (! gegl_node_process_success (sink, &error))
     {
-      /* Expected error is "Error opening file “/tmp/.ZBD4YZ”: Permission denied" */
-      success = (error                       &&
-                 error->domain == G_IO_ERROR &&
-                 error->code == G_IO_ERROR_PERMISSION_DENIED);
-    }
-  if (! success)
-    {
-      fprintf (stderr,
-               "- %s: Expected error message (domain: %d - code: %d): Error opening file “/some/tmp/path”: 
Permission denied\n",
-               G_STRFUNC, G_IO_ERROR, G_IO_ERROR_PERMISSION_DENIED);
-      if (error)
-        fprintf (stderr, "- %s: Actual error message (domain: %d - code: %d): %s\n",
-                 G_STRFUNC, error->domain, error->code, error->message);
-      else
-        fprintf (stderr, "- %s: No error message!\n", G_STRFUNC);
+      if (error                                                &&
+          error->domain == g_quark_from_static_string ("gegl:load-png-error-quark") &&
+          error->code == 0)
+        status = SUCCESS;
     }
+  MORE_INFO ("[gegl:png-load] failed to read file '/some/tmp/path': [86][7F][00][00]: invalid chunk type",
+             g_quark_from_static_string ("gegl:load-png-error-quark"), 0);
 
   g_object_unref (graph);
   g_clear_error (&error);
@@ -165,21 +185,21 @@ load_denied (void)
   g_unlink (path);
   g_free (path);
 
-  return success;
+  return status;
 }
 
 /* Trying to load an empty file (i.e. not valid PNG) with
  * gegl_node_blit_buffer(). */
-static gboolean
+static gint
 load_zero_blit (void)
 {
   GeglNode   *graph;
   GeglNode   *source;
   GeglNode   *scale;
-  GeglBuffer *buffer  = NULL;
-  GError     *error   = NULL;
+  GeglBuffer *buffer = NULL;
+  GError     *error  = NULL;
   gchar      *path;
-  gboolean    success = FALSE;
+  gint        status = FAILURE;
   gint        fd;
 
   /* Create a new empty file. It is not a valid PNG image. */
@@ -206,22 +226,12 @@ load_zero_blit (void)
 
   if (! gegl_node_process_success (scale, &error))
     {
-      /* Expected error: "too short for a png file, only 0 bytes." */
-      success = (error &&
-                 error->domain == g_quark_from_static_string ("gegl:load-png-error-quark") &&
-                 error->code == 0);
-    }
-  if (! success)
-    {
-      fprintf (stderr,
-               "- %s: Expected error message (domain: %d - code: %d): too short for a png file, only 0 
bytes.\n",
-               G_STRFUNC, g_quark_from_static_string ("egl:load-png-error-quark"), 0);
-      if (error)
-        fprintf (stderr, "- %s: Actual error message (domain: %d - code: %d): %s\n",
-                 G_STRFUNC, error->domain, error->code, error->message);
-      else
-        fprintf (stderr, "- %s: No error message!\n", G_STRFUNC);
+      if (error &&
+          error->domain == g_quark_from_static_string ("gegl:load-png-error-quark") &&
+          error->code == 0)
+        status = SUCCESS;
     }
+  MORE_INFO ("too short for a png file, only 0 bytes.", g_quark_from_static_string 
("gegl:load-png-error-quark"), 0);
 
   g_object_unref (graph);
   g_clear_error (&error);
@@ -232,11 +242,11 @@ load_zero_blit (void)
   g_unlink (path);
   g_free (path);
 
-  return success;
+  return status;
 }
 
 /* Trying to save a mp4 video with impossible dimensions. */
-static gboolean
+static gint
 save_invalid_mp4 (void)
 {
   GeglNode  *graph;
@@ -244,9 +254,9 @@ save_invalid_mp4 (void)
   GeglNode  *crop;
   GeglNode  *save;
   GeglColor *red;
-  GError    *error   = NULL;
+  GError    *error  = NULL;
   gchar     *path;
-  gboolean   success = FALSE;
+  gint       status = FAILURE;
   gint       fd;
 
   red = gegl_color_new ("rgb(1.0, 0.0, 0.0)");
@@ -279,21 +289,12 @@ save_invalid_mp4 (void)
        * libx264 does not allow odd dimensions for MP4 format and therefore the
        * export to video should fail.
        */
-      success = (error &&
-                 error->domain == g_quark_from_static_string ("gegl:ff-save") &&
-                 error->code == 0);
-    }
-  if (! success)
-    {
-      fprintf (stderr,
-               "- %s: Expected error message (domain: %d - code: %d): [libx264 @ 0x0123456] width not 
divisible by 2 (101x101)\n",
-               G_STRFUNC, g_quark_from_static_string ("gegl:ff-save"), 0);
-      if (error)
-        fprintf (stderr, "- %s: Actual error message (domain: %d - code: %d): %s\n",
-                 G_STRFUNC, error->domain, error->code, error->message);
-      else
-        fprintf (stderr, "- %s: No error message!\n", G_STRFUNC);
+      if (error &&
+          error->domain == g_quark_from_static_string ("gegl:ff-save") &&
+          error->code == 0)
+        status = SUCCESS;
     }
+  MORE_INFO ("[libx264 @ 0x0123456] width not divisible by 2 (101x101)", g_quark_from_static_string 
("gegl:ff-save"), 0);
 
   g_object_unref (graph);
   g_clear_error (&error);
@@ -302,15 +303,16 @@ save_invalid_mp4 (void)
   g_unlink (path);
   g_free (path);
 
-  return success;
+  return status;
 }
 
 int
 main (int argc, char **argv)
 {
-  gint tests_run    = 0;
-  gint tests_passed = 0;
-  gint tests_failed = 0;
+  gint tests_run     = 0;
+  gint tests_passed  = 0;
+  gint tests_failed  = 0;
+  gint tests_skipped = 0;
 
   gegl_init (0, NULL);
   g_object_set (G_OBJECT (gegl_config()),
@@ -319,13 +321,16 @@ main (int argc, char **argv)
                 NULL);
 
   RUN_TEST (save_denied);
-  RUN_TEST (load_denied);
+  RUN_TEST (load_incomplete);
   RUN_TEST (load_zero_blit);
   RUN_TEST (save_invalid_mp4);
 
   gegl_exit ();
 
-  if (tests_passed == tests_run)
+  if (tests_failed > 0)
+    return FAILURE;
+  else if (tests_passed > 0)
     return SUCCESS;
-  return FAILURE;
+  else
+    return SKIP;
 }