[devhelp] util: add dh_util_get_possible_index_files()

[Sébastien Wilmet <swilmet src gnome org>]

commit 72f8e5f607a25726901a79d69e48da6c9f4e050c
Author: Sébastien Wilmet <swilmet gnome org>
Date:   Sat Dec 23 19:22:38 2017 +0100

    util: add dh_util_get_possible_index_files()
    
    This will be useful in DhBookManager, but is written in dh-util so that
    it can be unit-tested.
    
    Add also my copyright to dh-util.h, in 2015 I've also added a util
    function.

 src/dh-util.c          |   44 ++++++++++++++++++++++
 src/dh-util.h          |    3 +
 unit-tests/Makefile.am |    3 +
 unit-tests/test-util.c |   97 ++++++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 147 insertions(+), 0 deletions(-)
---
diff --git a/src/dh-util.c b/src/dh-util.c
index bcb7f92..81fd93c 100644
--- a/src/dh-util.c
+++ b/src/dh-util.c
@@ -304,3 +304,47 @@ _dh_util_free_book_tree (GNode *book_tree)
 
         g_node_destroy (book_tree);
 }
+
+/* Returns: (transfer full) (element-type GFile): the list of possible Devhelp
+ * index files in @book_directory, in order of preference.
+ */
+GSList *
+dh_util_get_possible_index_files (GFile *book_directory)
+{
+        const gchar *extensions[] = {
+                ".devhelp2",
+                ".devhelp2.gz",
+                ".devhelp",
+                ".devhelp.gz",
+                NULL
+        };
+        gchar *directory_name;
+        GSList *list = NULL;
+        gint i;
+
+        g_return_val_if_fail (G_IS_FILE (book_directory), NULL);
+
+        directory_name = g_file_get_basename (book_directory);
+        g_return_val_if_fail (directory_name != NULL, NULL);
+
+        for (i = 0; extensions[i] != NULL; i++) {
+                const gchar *cur_extension = extensions[i];
+                gchar *index_file_name;
+                GFile *index_file;
+
+                /* The name of the directory the index file is in and the name
+                 * of the index file (minus the extension) must match.
+                 */
+                index_file_name = g_strconcat (directory_name, cur_extension, NULL);
+
+                index_file = g_file_get_child (book_directory, index_file_name);
+                list = g_slist_prepend (list, index_file);
+
+                g_free (index_file_name);
+        }
+
+        list = g_slist_reverse (list);
+
+        g_free (directory_name);
+        return list;
+}
diff --git a/src/dh-util.h b/src/dh-util.h
index b34cc0f..7eaa335 100644
--- a/src/dh-util.h
+++ b/src/dh-util.h
@@ -2,6 +2,7 @@
 /*
  * Copyright (C) 2001-2002 Mikael Hallendal <micke imendio com>
  * Copyright (C) 2004,2008 Imendio AB
+ * Copyright (C) 2015, 2017 Sébastien Wilmet <swilmet gnome org>
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License as
@@ -50,6 +51,8 @@ void         dh_util_queue_concat                 (GQueue *q1,
 G_GNUC_INTERNAL
 void         _dh_util_free_book_tree              (GNode *book_tree);
 
+GSList *     dh_util_get_possible_index_files     (GFile *book_directory);
+
 G_END_DECLS
 
 #endif /* DH_UTIL_H */
diff --git a/unit-tests/Makefile.am b/unit-tests/Makefile.am
index e57e34e..66c58c2 100644
--- a/unit-tests/Makefile.am
+++ b/unit-tests/Makefile.am
@@ -15,6 +15,9 @@ UNIT_TEST_PROGS =
 UNIT_TEST_PROGS += test-link
 test_link_SOURCES = test-link.c
 
+UNIT_TEST_PROGS += test-util
+test_util_SOURCES = test-util.c
+
 noinst_PROGRAMS = $(UNIT_TEST_PROGS)
 TESTS = $(UNIT_TEST_PROGS)
 
diff --git a/unit-tests/test-util.c b/unit-tests/test-util.c
new file mode 100644
index 0000000..0f9b895
--- /dev/null
+++ b/unit-tests/test-util.c
@@ -0,0 +1,97 @@
+/*
+ * Copyright (C) 2017 Sébastien Wilmet <swilmet gnome org>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "dh-util.h"
+
+static void
+check_get_possible_index_files (const gchar *book_directory_path,
+                                const gchar *book_basename)
+{
+        GFile *book_directory;
+        GSList *list;
+        GSList *l;
+        gint i;
+
+        book_directory = g_file_new_for_path (book_directory_path);
+        list = dh_util_get_possible_index_files (book_directory);
+
+        g_assert_cmpint (g_slist_length (list), ==, 4);
+
+        for (l = list, i = 0; l != NULL; l = l->next, i++) {
+                GFile *index_file = G_FILE (l->data);
+                gchar *expected_basename;
+                gchar *basename;
+                gchar *expected_path;
+                gchar *path;
+
+                switch (i) {
+                        case 0:
+                                expected_basename = g_strconcat (book_basename, ".devhelp2", NULL);
+                                break;
+
+                        case 1:
+                                expected_basename = g_strconcat (book_basename, ".devhelp2.gz", NULL);
+                                break;
+
+                        case 2:
+                                expected_basename = g_strconcat (book_basename, ".devhelp", NULL);
+                                break;
+
+                        case 3:
+                                expected_basename = g_strconcat (book_basename, ".devhelp.gz", NULL);
+                                break;
+
+                        default:
+                                g_assert_not_reached ();
+                }
+
+                basename = g_file_get_basename (index_file);
+                g_assert_cmpstr (basename, ==, expected_basename);
+
+                expected_path = g_build_filename (book_directory_path, expected_basename, NULL);
+                path = g_file_get_path (index_file);
+                g_assert_cmpstr (path, ==, expected_path);
+
+                g_free (expected_basename);
+                g_free (basename);
+                g_free (expected_path);
+                g_free (path);
+        }
+
+        g_object_unref (book_directory);
+        g_slist_free_full (list, g_object_unref);
+}
+
+static void
+test_get_possible_index_files (void)
+{
+        check_get_possible_index_files ("/usr/share/gtk-doc/html/glib", "glib");
+        check_get_possible_index_files ("/usr/share/gtk-doc/html/glib/", "glib");
+        check_get_possible_index_files ("/usr/share/gtk-doc/html/gtk3", "gtk3");
+        check_get_possible_index_files ("/usr/share/gtk-doc/html/gtk3/", "gtk3");
+}
+
+int
+main (int    argc,
+      char **argv)
+{
+        g_test_init (&argc, &argv, NULL);
+
+        g_test_add_func ("/util/get_possible_index_files", test_get_possible_index_files);
+
+        return g_test_run ();
+}