Add base::get_absolute_path_from_relative() function

[Gasparoken]

Part of aseprite/aseprite#4851

It's wanted to reconstruct the absolute path starting from the relative/absolute filename in the filename entry of 'Export As' dialog.

[aseprite-bot]

clang-tidy made some suggestions

[aseprite-bot]

warning: the 'empty' method should be used to check for emptiness instead of 'size' [readability-container-size-empty]

Suggested change

	if (relativeParts.size() >= 1 && relativeParts[0] == "")
	if (!relativeParts.empty() && relativeParts[0] == "")

Additional context

/usr/include/c++/13/bits/stl_vector.h:1087: method 'vector'::empty() defined here

      empty() const _GLIBCXX_NOEXCEPT
      ^

[aseprite-bot]

warning: the 'empty' method should be used to check for emptiness instead of comparing to an empty object [readability-container-size-empty]

Suggested change

	if (relativeParts.size() >= 1 && relativeParts[0] == "")
	if (relativeParts.size() >= 1 && relativeParts[0].empty())

Additional context

/usr/include/c++/13/bits/basic_string.h:1219: method 'basic_string'::empty() defined here

      empty() const _GLIBCXX_NOEXCEPT
      ^

[dacap]

Hi @Gasparoken, just in case, is possible that base::get_absolute_path() does the job? (it removes ".." elements, etc.)

[Gasparoken]

base::get_absolute_path() uses the current folder instead of an arbitrary base_path. That's why I implemented this new function. But maybe base::get_absolute_path() is enough and I just need to change the approach in Aseprite (particularly on std::string ExportFileWindow::outputFilenameValue() const). Let me investigate.

[dacap]

base::get_absolute_path() uses the current folder instead of an arbitrary base_path

It should work as a path normalizer if the given path is an absolute path; you can check out the tests:

laf/base/fs_tests.cpp

Lines 246 to 250 in c84b89b

	#if LAF_WINDOWS
	EXPECT_EQ("C:\\file", get_absolute_path("C:/path/../file"));
	#else
	EXPECT_EQ("/file", get_absolute_path("/path/../file"));
	#endif

So you should be able to use something like base::get_absolute_path(base::join_path(base_path, relative_path)). Other way is using base::normalize_path() directly.

[Gasparoken]

That's great! However, I found that base::get_absolute_path() can only handle one "../", if there are two or more "../", the function does not get to the correct folder level. Therefore, the following line fails:

EXPECT_EQ("/user/file", get_absolute_path("/user/name/path/../../file"));

I'll adopt this function to resolve aseprite/aseprite#4851, but I will need to fix the indicated bug first.

[Gasparoken]

I'm closing this and will take the base::get_absolute_path() approach instead.