Add a header comment to generated files

Author: dempseyatgithub

BuildSettingExtractor/BuildSettingExtractor.m

@@ -103,21 +103,32 @@ - (void)writeConfigFilesToDestinationFolder:(NSURL *)destinationURL {
     [self.buildSettingsByTarget enumerateKeysAndObjectsUsingBlock:^(id targetName, id obj, BOOL *stop) {
         [obj enumerateKeysAndObjectsUsingBlock:^(id configName, id settings, BOOL *stop) {
 
+            NSString *filename = [self configFilenameWithTargetName:targetName configName:configName];
+
+            NSString *configFileString = @"";
+
+            // Add header comment
+            NSString *headerComment = [self headerCommentForFilename:filename];
+            if (headerComment) {
+                configFileString = [configFileString stringByAppendingString:headerComment];
+            }
+
             // If the config name is not the shared config, we need to import the shared config
             if (![configName isEqualToString:self.sharedConfigName]) {
                 NSString *configFilename = [self configFilenameWithTargetName:targetName configName:self.sharedConfigName];
                 NSString *includeDirective = [NSString stringWithFormat:@"#include \"%@\"\n\n", configFilename];
-                settings = [includeDirective stringByAppendingString:settings];
+                configFileString = [configFileString stringByAppendingString:includeDirective];
             }
 
+            configFileString = [configFileString stringByAppendingString:settings];
+
             // Trim whitespace and newlines
-            settings = [settings stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]];
+            configFileString = [configFileString stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]];
 
-            NSString *filename = [self configFilenameWithTargetName:targetName configName:configName];
 
             NSURL *fileURL = [destinationURL URLByAppendingPathComponent:filename];
 
-            BOOL success = [settings writeToURL:fileURL atomically:YES encoding:NSUTF8StringEncoding error:nil];
+            BOOL success = [configFileString writeToURL:fileURL atomically:YES encoding:NSUTF8StringEncoding error:nil];
             if (!success) NSLog(@"No success with %@", fileURL);
         }];
     }];
@@ -128,6 +139,23 @@ - (NSString *)configFilenameWithTargetName:(NSString *)targetName configName:(NS
     return [NSString stringWithFormat:@"%@-%@.xcconfig", targetName, configName];
 }
 
+// Given the filename generate the header comment
+- (NSString *)headerCommentForFilename:(NSString *)filename {
+    NSString *headerComment = @"";
+
+    NSString *dateString = [NSDateFormatter localizedStringFromDate:[NSDate date] dateStyle:NSDateFormatterShortStyle timeStyle:NSDateFormatterNoStyle];
+
+    headerComment = [headerComment stringByAppendingString:@"//\n"];
+    headerComment = [headerComment stringByAppendingFormat:@"// %@\n", filename];
+    headerComment = [headerComment stringByAppendingString:@"//\n"];
+    headerComment = [headerComment stringByAppendingFormat:@"// Generated by BuildSettingExtractor on %@\n", dateString];
+    headerComment = [headerComment stringByAppendingString:@"// https://github.com/dempseyatgithub/BuildSettingExtractor\n"];
+    headerComment = [headerComment stringByAppendingString:@"//\n"];
+    headerComment = [headerComment stringByAppendingString:@"\n"];
+
+    return headerComment;
+}
+
 
 /* Given a build setting dictionary, returns a string representation of the build settings, suitable for an xcconfig file. */
 - (NSString *)stringRepresentationOfBuildSettings:(NSDictionary *)buildSettings {