feat(cli): implement concrete iterate directory function

Author: nooneknowspeter

src/cli/cli.zig

@@ -32,6 +32,46 @@ const CLI = struct {
     list_of_chapter_support_files: STD.ArrayList([]const u8) = .empty,
 };
 
+pub fn iterateDirectory(
+    allocator: STD.mem.Allocator,
+    extra_options: struct {
+        dir_path: []const u8 = "exercises",
+    },
+) !STD.ArrayList([]const u8) {
+    var list_of_contents: STD.ArrayList([]const u8) = .empty;
+
+    const TOP_LEVEL_DIR = try STD.fs.cwd().openDir(extra_options.dir_path, .{ .iterate = true });
+    var chapters = TOP_LEVEL_DIR.iterate();
+
+    while (try chapters.next()) |chapter| {
+        const CHAPTER_DIR_PATH = try STD.fs.path.join(allocator, &.{ extra_options.dir_path, chapter.name });
+
+        const CHAPTER_DIR = try STD.fs.cwd().openDir(CHAPTER_DIR_PATH, .{ .iterate = true });
+        var contents = CHAPTER_DIR.iterate();
+
+        while (try contents.next()) |content| {
+            const CONTENT_FILE_PATH = try STD.fs.path.join(allocator, &.{ extra_options.dir_path, chapter.name, content.name });
+
+            if (STD.mem.containsAtLeast(u8, content.name, 1, ".cpp")) {
+                try list_of_contents.append(allocator, CONTENT_FILE_PATH);
+            }
+        }
+    }
+
+    STD.sort.insertion(
+        []const u8,
+        list_of_contents.items,
+        {},
+        struct {
+            fn lessThan(_: void, a: []const u8, b: []const u8) bool {
+                return STD.mem.lessThan(u8, a, b);
+            }
+        }.lessThan,
+    );
+
+    return list_of_contents;
+}
+
 fn iterateExerciseDirectory(
     self: *CLI,
     exercise_dir: struct { dir_path: []const u8 = "exercises" },