My code is crashing Xcode (or even macOS kernel) during debugging - Xcode just vanishes from screen!
// pseudo code
public func hunt(in directory: URL) {
let fileIterator = fileMan.enumerator(at: directory)
// collect app packages into a list
var packages = [URL]()
for case let fileURL as URL in fileIterator {
if fileURL.pathExtension == "app" { packages.append(fileURL) }
}
// FileWrappers
var wrappers = [FileWrappers]()
for packageURL in packages {
//!!! The line below eventually crashes Xcode (or even macOS kernel once)!
wrappers[packageURL] = try? FileWrapper(url: packageURL, options: .immediate)
// NOTE: I need FileWrapper.matchesContents later in some code
}
}
// unit test case
func test() {}
myObj.hunt(in: URL(fileURLWithPath: "/Applications"))
}
I suspect that the FileWrapper constructor is traversing directories and encounter cyclic symbolic links and eventually it crashes; since it's running at system runtime level, most probably it also crashes macOS kernel!
So my question is that is there any way to detect cyclic symbolic links so that I can design my own logics similar to FileWrapper?
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After upgrading to Xcode 15.1 on Sonoma, I get a very weird problem in an on-going project.
This source file has no syntax coloring. No matter how I try "Open As->Source Code" it just won't work. All other files (sources/resources) work fine.
Is this a known bug? Is there any way to get syntax coloring back?
I have a need to optimize reading strategy, based on if the file is on hard disk or SSD. Does macOS provide any low-level API so that I can query such information?
I am reluctant to admit that I only came to know that Swift provides a builtin documentation markup syntax just a few months ago.
/** Test func
Some description here.
- Parameters:
- b:Test
- d: Test
- f: Test
- Returns: Bool
*/
func myMethod(a b:Int, c d:Int, e f:Int) -> Bool { b > d }
It seems the markup is pretty simple and has only a few keywords. But, I want to read through the complete reference. Any useful pointers?
I have a single-line label whose purpose is display file path, possibly very long.
Is there any way to shorten/compact the path string (with ellipse ...) so that the label still displays full path even it's too long?
Like below:
/some/very/long/path/to/some/filename.txt
to
/some/.../filename.txt
I am trying to add rows to GridView and not able to get expected row height correctly.
override func viewDidLoad() {
super.viewDidLoad()
// Remove the row in IB designer
gridView.removeRow(at: 0)
let image = NSImage(named: NSImage.colorPanelName)!
//image.size = NSMakeSize(80, 80)
let imageView = NSImageView(image: image)
imageView.imageFrameStyle = .grayBezel
imageView.imageScaling = .scaleAxesIndependently
imageView.frame = NSMakeRect(0, 0, 80, 80)
let label = NSTextField(labelWithString: "test text")
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row.height = 80
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What was wrong with my code?
I vaguely remember I came across some classes about file packages. Just cannot recall the exact names. Can anyone help?
I have the following in my .zshrc:
export MY_LIBRARY_DIR=~/bin
In Xcode I can set header/lib search path using something like $(MY_LIBRARY_DIR)/abc.
This works fine in my daily used user account. But today I found that this technique does not work in a test user account (for testing purpose only).
I even reboot my machine but still can't get it working.
Am I missing something very obvious???
BTW, I am using Xcode 14.2 and 14.3.1.
Does Swift support this? Til now my understanding is that reflection only works with public members. Is it possible to get private/static members of a type?
I want to read metadata of image files such as copyright, author etc.
I did a web search and the closest thing is CGImageSourceCopyPropertiesAtIndex:
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NSDictionary* metadata = [[NSDictionary alloc] init];
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NSString* rowData = [fileList objectAtIndex:[tblFileList selectedRow]];
//set path to file selected
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//declare a file manager
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//escape all the garbage in the string
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NSError* error;
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NSLog(@"%@", metadata);
[filePathURL release];
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[self showAlert:@"I cannot find this file."];
}
[fileManager release];
}
Is there any better or easy approach than this?
Per the docs, NSImage.imageTypes returns a list UTI's, something like below:
com.adobe.pdf
com.apple.pict
com.adobe.encapsulated-postscript
public.jpeg
public.png
com.compuserve.gif
com.canon.tif-raw-image
...
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Does Cocoa provide any API to query for this information?
In C++, I can write 123457890ull to imply it's an unsigned long long integer. Does Swift provide similar language construct?
I am aware Swift deliberately hides details (the actual index number) for safety, by introducing this verbose construct.
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I want to convert byte size strings like "1234kb", "100mb" or "5gb" to their actual number representation. Is there any builtin functions for this purpose?
I have had this issue for a long time. If I configure any auto layout constraints in TableViewCell, I get extremely weird layout behavior in IB designer; however, layout is completely good during runtime.
For example, with a completely new project and a single NSTableView on the main view, I get:
If I resize main view, the tableview won't get resized
Every time I reopen the project, the tableview would shrink by height.
It seems the shrinked height is doubled every time. For example, in the following screenshot, the gap is 56. Next reopen will double the gap to 112.
Is this a known bug? I would want to file bug report at https://feedbackassistant.apple.com.