Rewrite [Pastelog collectLogsWithErrorString] in Swift

This change should have no direct user impact.

Signal/src/util/Pastelog.m

@@ -201,51 +201,19 @@ typedef NS_ERROR_ENUM(PastelogErrorDomain, PastelogError) {
 {
     OWSAssertIsOnMainThread();
 
-    NSString *errorString;
-    NSString *logsDirPath = [self collectLogsWithErrorString:&errorString];
-    if (!logsDirPath) {
+    CollectedLogsResult *collectedLogsResult = [self collectLogs];
+    if (!collectedLogsResult.succeeded) {
+        NSString *errorString = collectedLogsResult.errorString;
         [Pastelog showFailureAlertWithMessage:errorString ?: @"(unknown error)" logArchiveOrDirectoryPath:nil];
         return;
     }
+    NSString *logsDirPath = collectedLogsResult.logsDirPath;
 
     [AttachmentSharing showShareUIForURL:[NSURL fileURLWithPath:logsDirPath]
                                   sender:nil
                               completion:^{ (void)[OWSFileSystem deleteFile:logsDirPath]; }];
 }
 
-- (nullable NSString *)collectLogsWithErrorString:(NSString *_Nullable *_Nonnull)errorString
-{
-    NSDateFormatter *dateFormatter = [NSDateFormatter new];
-    [dateFormatter setLocale:[NSLocale currentLocale]];
-    [dateFormatter setDateFormat:@"yyyy.MM.dd hh.mm.ss"];
-    NSString *dateString = [dateFormatter stringFromDate:[NSDate new]];
-    NSString *logsName = [[dateString stringByAppendingString:@" "] stringByAppendingString:NSUUID.UUID.UUIDString];
-
-    NSString *zipDirPath = [OWSTemporaryDirectory() stringByAppendingPathComponent:logsName];
-    [OWSFileSystem ensureDirectoryExists:zipDirPath];
-
-    NSArray<NSString *> *logFilePaths = DebugLogger.shared.allLogFilePaths;
-    if (logFilePaths.count < 1) {
-        *errorString
-            = NSLocalizedString(@"DEBUG_LOG_ALERT_NO_LOGS", @"Error indicating that no debug logs could be found.");
-        return nil;
-    }
-
-    for (NSString *logFilePath in logFilePaths) {
-        NSString *copyFilePath = [zipDirPath stringByAppendingPathComponent:logFilePath.lastPathComponent];
-        NSError *error;
-        if (![[NSFileManager defaultManager] copyItemAtPath:logFilePath toPath:copyFilePath error:&error]) {
-            OWSLogError(@"could not copy log file at %@: %@", logFilePath, error);
-            // Write the error to the file that would have been copied.
-            [[error description] writeToFile:copyFilePath atomically:YES encoding:NSUTF8StringEncoding error:NULL];
-            // We still want to get *some* of the logs.
-            continue;
-        }
-        [OWSFileSystem protectFileOrFolderAtPath:copyFilePath];
-    }
-    return zipDirPath;
-}
-
 - (void)uploadLogsWithSuccess:(UploadDebugLogsSuccess)successParam failure:(UploadDebugLogsFailure)failureParam
 {
     OWSAssertDebug(successParam);
@@ -258,12 +226,13 @@ typedef NS_ERROR_ENUM(PastelogErrorDomain, PastelogError) {
     };
 
     // Phase 1. Make a local copy of all of the log files.
-    NSString *errorString;
-    NSString *zipDirPath = [self collectLogsWithErrorString:&errorString];
-    if (!zipDirPath) {
+    CollectedLogsResult *collectedLogsResult = [self collectLogs];
+    if (!collectedLogsResult.succeeded) {
+        NSString *errorString = collectedLogsResult.errorString;
         failure(errorString, nil);
         return;
     }
+    NSString *zipDirPath = collectedLogsResult.logsDirPath;
 
     // Phase 2. Zip up the log files.
     NSString *zipFilePath = [zipDirPath stringByAppendingPathExtension:@"zip"];

Signal/src/util/Pastelog.swift

@@ -135,3 +135,67 @@ public class DebugLogUploader: NSObject {
         }
     }
 }
+
+extension Pastelog {
+    /// The result of the `collectLogs` method. Here because Objective-C can't represent `Result`s.
+    /// If we migrate its callers to Swift, we should be able to remove this class.
+    @objc
+    public class CollectedLogsResult: NSObject {
+        @objc
+        public let errorString: String?
+
+        @objc
+        public let logsDirPath: String?
+
+        @objc
+        public var succeeded: Bool { errorString == nil }
+
+        init(errorString: String) {
+            self.errorString = errorString
+            self.logsDirPath = nil
+            super.init()
+        }
+
+        init(logsDirPath: String) {
+            self.errorString = nil
+            self.logsDirPath = logsDirPath
+            super.init()
+        }
+    }
+
+    @objc
+    func collectLogs() -> CollectedLogsResult {
+        let dateFormatter = DateFormatter()
+        dateFormatter.dateFormat = "yyyy.MM.dd hh.mm.ss"
+        let dateString = dateFormatter.string(from: Date())
+        let logsName = "\(dateString) \(UUID().uuidString)"
+
+        let zipDirUrl = URL(fileURLWithPath: OWSTemporaryDirectory()).appendingPathComponent(logsName)
+        let zipDirPath = zipDirUrl.path
+        OWSFileSystem.ensureDirectoryExists(zipDirPath)
+
+        let logFilePaths = DebugLogger.shared().allLogFilePaths()
+        if logFilePaths.isEmpty {
+            let errorString = NSLocalizedString(
+                "DEBUG_LOG_ALERT_NO_LOGS",
+                comment: "Error indicating that no debug logs could be found."
+            )
+            return CollectedLogsResult(errorString: errorString)
+        }
+
+        for logFilePath in logFilePaths {
+            let lastLogFilePathComponent = URL(fileURLWithPath: logFilePath).lastPathComponent
+            let copyFilePath = zipDirUrl.appendingPathComponent(lastLogFilePathComponent).path
+            do {
+                try FileManager.default.copyItem(atPath: logFilePath, toPath: copyFilePath)
+            } catch {
+                Logger.error("could not copy log file at \(logFilePath): \(error)")
+                // Write the error to the file that would have been copied.
+                try? error.localizedDescription.write(toFile: copyFilePath, atomically: true, encoding: .utf8)
+            }
+            OWSFileSystem.protectFileOrFolder(atPath: copyFilePath)
+        }
+
+        return CollectedLogsResult(logsDirPath: zipDirPath)
+    }
+}