* fixing backslash tokens

Author: itod

ParserGenApp/PGTokenKindDescriptor.m

@@ -48,9 +48,6 @@ + (PGTokenKindDescriptor *)descriptorWithStringValue:(NSString *)s name:(NSStrin
     if (!desc) {
         desc = [[[PGTokenKindDescriptor alloc] init] autorelease];
 
-        // escape back slases
-        s = [s stringByReplacingOccurrencesOfString:@"\\" withString:@"\\\\"];
-
         // escape double quotes
         s = [s stringByReplacingOccurrencesOfString:@"\"" withString:@"\\\""];
 

res/quote_symbol.grammar

@@ -5,6 +5,7 @@
 }
 
 start = sym+;
-sym = single | double;
+sym = single | double | back;
 single = "'";
-double = '"';
+double = '"';
+back = '\\';

test/QuoteSymbolParser.h

@@ -3,6 +3,7 @@
 enum {
     QUOTESYMBOL_TOKEN_KIND_SINGLE = 14,
     QUOTESYMBOL_TOKEN_KIND_DOUBLE,
+    QUOTESYMBOL_TOKEN_KIND_BACK,
 };
 
 @interface QuoteSymbolParser : PKParser

test/QuoteSymbolParser.m

@@ -15,9 +15,11 @@ - (id)initWithDelegate:(id)d {
         self.startRuleName = @"start";
         self.tokenKindTab[@"'"] = @(QUOTESYMBOL_TOKEN_KIND_SINGLE);
         self.tokenKindTab[@"\""] = @(QUOTESYMBOL_TOKEN_KIND_DOUBLE);
+        self.tokenKindTab[@"\\"] = @(QUOTESYMBOL_TOKEN_KIND_BACK);
 
         self.tokenKindNameTab[QUOTESYMBOL_TOKEN_KIND_SINGLE] = @"'";
         self.tokenKindNameTab[QUOTESYMBOL_TOKEN_KIND_DOUBLE] = @"\"";
+        self.tokenKindNameTab[QUOTESYMBOL_TOKEN_KIND_BACK] = @"\\";
 
     }
     return self;
@@ -47,7 +49,7 @@ - (void)start_ {
 
     do {
         [self sym_]; 
-    } while ([self predicts:QUOTESYMBOL_TOKEN_KIND_DOUBLE, QUOTESYMBOL_TOKEN_KIND_SINGLE, 0]);
+    } while ([self predicts:QUOTESYMBOL_TOKEN_KIND_BACK, QUOTESYMBOL_TOKEN_KIND_DOUBLE, QUOTESYMBOL_TOKEN_KIND_SINGLE, 0]);
 
     [self fireDelegateSelector:@selector(parser:didMatchStart:)];
 }
@@ -58,6 +60,8 @@ - (void)sym_ {
         [self single_]; 
     } else if ([self predicts:QUOTESYMBOL_TOKEN_KIND_DOUBLE, 0]) {
         [self double_]; 
+    } else if ([self predicts:QUOTESYMBOL_TOKEN_KIND_BACK, 0]) {
+        [self back_]; 
     } else {
         [self raise:@"No viable alternative found in rule 'sym'."];
     }
@@ -79,4 +83,11 @@ - (void)double_ {
     [self fireDelegateSelector:@selector(parser:didMatchDouble:)];
 }
 
+- (void)back_ {
+    
+    [self match:QUOTESYMBOL_TOKEN_KIND_BACK discard:NO]; 
+
+    [self fireDelegateSelector:@selector(parser:didMatchBack:)];
+}
+
 @end

test/QuoteSymbolParserTest.m

@@ -100,4 +100,24 @@ - (void)testDoubleSpaceDoubleSpaceDouble {
     TDEqualObjects(TDAssembly(@"[\", \", \"]\"/\"/\"^"), [res description]);
 }
 
+- (void)testBackBackBack {
+    NSString *s = @"\\\\\\";
+    
+    NSError *err = nil;
+    PKAssembly *res = [_parser parseString:s error:&err];
+    TDNil(err);
+    
+    TDEqualObjects(TDAssembly(@"[\\, \\, \\]\\/\\/\\^"), [res description]);
+}
+
+- (void)testBackSpaceBackSpaceBack {
+    NSString *s = @"\\ \\ \\";
+    
+    NSError *err = nil;
+    PKAssembly *res = [_parser parseString:s error:&err];
+    TDNil(err);
+    
+    TDEqualObjects(TDAssembly(@"[\\, \\, \\]\\/\\/\\^"), [res description]);
+}
+
 @end