Implement -[NSString enumerateLinesUsingBlock:] (#407)

* Implement -[NSString enumerateLinesUsingBlock:]

* Fix formatting

* Use GNUstep CALL_BLOCK macro

ChangeLog

@@ -5,6 +5,13 @@
 	Improve implementation of BETWEEN operator in NSPredicate
 	for data types other than NSNumber. Proper support
 	for constant values.
+  
+2024-05-18 Hugo Melder <hugo@algoriddim.com>
+
+	* Source/NSString.m:
+	* Headers/Foundation/NSString.h:
+	* Tests/base/NSString/enumerateLinesUsingBlock.m:
+	Implemented -[NSString enumerateLinesUsingBlock:].
 
 2024-04-30 Richard Frith-Macdonald <rfm@gnu.org>
 

Headers/Foundation/NSString.h

@@ -466,6 +466,7 @@ enum {
 typedef NSUInteger NSStringEnumerationOptions;
 
 DEFINE_BLOCK_TYPE(GSNSStringEnumerationBlock, void, NSString* substring, NSRange substringRange, NSRange enclosingRange, BOOL* stop);
+DEFINE_BLOCK_TYPE(GSNSStringLineEnumerationBlock, void, NSString *line, BOOL *stop);
 #endif
 
 /**
@@ -1093,6 +1094,9 @@ GS_EXPORT_CLASS
 #endif	/* GS_API_NONE */
 
 #if OS_API_VERSION(MAC_OS_X_VERSION_10_6,GS_API_LATEST) 
+
+- (void) enumerateLinesUsingBlock: (GSNSStringLineEnumerationBlock)block;
+
 - (void) enumerateSubstringsInRange: (NSRange)range 
                             options: (NSStringEnumerationOptions)opts 
                          usingBlock: (GSNSStringEnumerationBlock)block;

MISSING

@@ -552,7 +552,6 @@ NSString:
 	- lowercaseStringWithLocale:
 	- capitalizedStringWithLocale:
 	- enumerateSubstringsInRange:options:usingBlock:
-	- enumerateLinesUsingBlock:
 	- getBytes:maxLength:usedLength:encoding:options:range:remainingRange:
 	- decomposedStringWithCanonicalMapping
 	- precomposedStringWithCanonicalMapping

Source/NSString.m

@@ -6271,6 +6271,39 @@ static NSFileManager *fm = nil;
   return [self rangeOfString: string].location != NSNotFound;
 }
 
+- (void) enumerateLinesUsingBlock: (GSNSStringLineEnumerationBlock)block
+{
+  NSUInteger length;
+  NSUInteger lineStart, lineEnd, contentsEnd;
+  NSRange	currentLocationRange;
+  BOOL stop;
+
+  length = [self length];
+  lineStart = lineEnd = contentsEnd = 0;
+  stop = NO;
+    
+  // Enumerate through the string line by line
+  while (lineStart < length && !stop) {
+    NSString *line;
+    NSRange lineRange;
+
+    currentLocationRange = NSMakeRange(lineStart, 0);
+    [self getLineStart: &lineStart
+                   end: &lineEnd
+           contentsEnd: &contentsEnd
+              forRange: currentLocationRange];
+      
+    lineRange = NSMakeRange(lineStart, contentsEnd - lineStart);
+    line = [self substringWithRange: lineRange];
+    
+    // Execute the block
+    CALL_BLOCK(block, line, &stop);
+    
+    // Move to the next line
+    lineStart = lineEnd;
+  }
+}
+
 - (void) enumerateSubstringsInRange: (NSRange)range 
                             options: (NSStringEnumerationOptions)opts 
                          usingBlock: (GSNSStringEnumerationBlock)block

Tests/base/NSString/enumerateLinesUsingBlock.m

@@ -0,0 +1,89 @@
+#import <Foundation/NSAutoreleasePool.h>
+#import <Foundation/NSString.h>
+#import <Foundation/NSArray.h>
+
+#import "Testing.h"
+
+#if defined(__has_extension) && __has_extension(blocks)
+
+BOOL testEnumerateSimpleLines() {
+  NSString *testString = @"First line\nSecond line\nThird line";
+  NSMutableArray *collectedLines = [NSMutableArray array];
+  NSArray *expectedLines = @[@"First line", @"Second line", @"Third line"];
+
+  [testString enumerateLinesUsingBlock: ^(NSString *line, BOOL *stop) {
+    [collectedLines addObject: line];
+  }];
+
+  return [collectedLines isEqualToArray: expectedLines];
+}
+
+BOOL testEnumerateCRLFLines() {
+  NSString *testString = @"First line\r\nSecond line\r\nThird line";
+  NSMutableArray *collectedLines = [NSMutableArray array];
+  NSArray *expectedLines = @[@"First line", @"Second line", @"Third line"];
+
+  [testString enumerateLinesUsingBlock: ^(NSString *line, BOOL *stop) {
+    [collectedLines addObject: line];
+  }];
+
+  return [collectedLines isEqualToArray: expectedLines];
+}
+
+BOOL testStopEarly() {
+  NSString *testString = @"First line\nSecond line\nThird line";
+  __block int lineCount = 0;
+
+  [testString enumerateLinesUsingBlock:^(NSString *line, BOOL *stop) {
+    lineCount++;
+    if ([line isEqualToString:@"Second line"]) {
+      *stop = YES;
+    }
+  }];
+
+  return lineCount == 2; // Should stop after the second line
+}
+
+BOOL testEmptyString() {
+  NSString *testString = @"";
+  __block BOOL blockCalled = NO;
+
+  [testString enumerateLinesUsingBlock:^(NSString *line, BOOL *stop) {
+    blockCalled = YES;
+  }];
+
+  return !blockCalled; // Block should not be called
+}
+
+BOOL testSingleLineNoBreaks() {
+  NSString *testString = @"Single line without line breaks";
+  __block NSString *receivedLine = nil;
+
+  [testString enumerateLinesUsingBlock:^(NSString *line, BOOL *stop) {
+    receivedLine = line;
+  }];
+
+  return [receivedLine isEqualToString:testString];
+}
+
+int main() {
+  NSAutoreleasePool *arp = [NSAutoreleasePool new];
+
+  PASS(testEnumerateSimpleLines(), "Should enumerate all lines correctly.");
+  PASS(testEnumerateCRLFLines(), "Should enumerate all CRLF lines correctly.");
+  PASS(testStopEarly(), "Should stop enumeration early as directed.");
+  PASS(testEmptyString(), "Should not call block for empty string.");
+  PASS(testSingleLineNoBreaks(), "Should handle single line without line breaks correctly.");
+
+  [arp release];
+  return 0;
+}
+
+#else
+
+int main (int argc, const char * argv[])
+{
+  return 0;
+}
+
+#endif