Fix assignment to array within struct #26
Merged
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
…gth]`. # Conflicts: # test/fiddle/test_import.rb
This was referenced Jan 22, 2020
nobu
reviewed
Jan 22, 2020
lib/fiddle/struct.rb
Outdated
|
|
||
| def []=(index, value) | ||
| if index < 0 || index >= size | ||
| raise RangeError, 'index %d outside of array bounds 0...%d' % [index, size] |
Contributor
Author
There was a problem hiding this comment.
Good idea, I changed this.
lib/fiddle/struct.rb
Outdated
| raise RangeError, 'index %d outside of array bounds 0...%d' % [index, size] | ||
| end | ||
|
|
||
| to_ptr[index * @align, @size] = [value].pack(@pack_format) |
Contributor
Author
There was a problem hiding this comment.
I agree this was wrong. I fixed the error, but I was unable to make it fail in a test case.
The test did not fail because, on my system, @align == @size for all primitive types. Therefore the result of using @align yields a correct value on my system, but could fail on other architectures. I modified the test case to attempt to write at several array indices, and then check that the underlying memory can be correctly unpacked. I think the modified test case covers the issue better than the original, even though I did not experience a failure, so I committed it.
# Conflicts: # lib/fiddle/struct.rb
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
2 participants
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
This pull request was split from #14 as requested by @nobu . It depends on #25 because that pull request makes it possible to access the underlying memory of a struct, which is required in order for this pull request to work properly.
When a member of a struct is an array,
CStructEntitywould return a temporary array containing those values. Assignment to that array was a no-op, which led to confusing behavior because an assignment to the array would be "ignored". I fixed this so that assignment to the returned array correctly updates the member within the struct.For example: