Bug 1326454 - Make TokenStream::skipChars{,IgnoreEOL} accept an unsigned integral number of chars to skip. r=arai

--HG--
extra : rebase_source : 1f823c6dbcd018372e7f4f3b6ee8612a22773cb8

js/src/frontend/TokenStream.cpp

@@ -8,6 +8,7 @@
 
 #include "frontend/TokenStream.h"
 
+#include "mozilla/ArrayUtils.h"
 #include "mozilla/IntegerTypeTraits.h"
 #include "mozilla/PodOperations.h"
 
@@ -33,6 +34,7 @@
 using namespace js;
 using namespace js::frontend;
 
+using mozilla::ArrayLength;
 using mozilla::Maybe;
 using mozilla::PodAssign;
 using mozilla::PodCopy;
@@ -956,7 +958,7 @@ TokenStream::getDirectives(bool isMultiline, bool shouldWarnDeprecated)
 
 bool
 TokenStream::getDirective(bool isMultiline, bool shouldWarnDeprecated,
-                          const char* directive, int directiveLength,
+                          const char* directive, uint8_t directiveLength,
                           const char* errorMsgPragma,
                           UniqueTwoByteChars* destination)
 {
@@ -1030,7 +1032,10 @@ TokenStream::getDisplayURL(bool isMultiline, bool shouldWarnDeprecated)
     // developer would like to refer to the source as from the source's actual
     // URL.
 
-    return getDirective(isMultiline, shouldWarnDeprecated, " sourceURL=", 11,
+    static const char sourceURLDirective[] = " sourceURL=";
+    constexpr uint8_t sourceURLDirectiveLength = ArrayLength(sourceURLDirective) - 1;
+    return getDirective(isMultiline, shouldWarnDeprecated,
+                        sourceURLDirective, sourceURLDirectiveLength,
                         "sourceURL", &displayURL_);
 }
 
@@ -1040,7 +1045,10 @@ TokenStream::getSourceMappingURL(bool isMultiline, bool shouldWarnDeprecated)
     // Match comments of the form "//# sourceMappingURL=<url>" or
     // "/\* //# sourceMappingURL=<url> *\/"
 
-    return getDirective(isMultiline, shouldWarnDeprecated, " sourceMappingURL=", 18,
+    static const char sourceMappingURLDirective[] = " sourceMappingURL=";
+    constexpr uint8_t sourceMappingURLDirectiveLength = ArrayLength(sourceMappingURLDirective) - 1;
+    return getDirective(isMultiline, shouldWarnDeprecated,
+                        sourceMappingURLDirective, sourceMappingURLDirectiveLength,
                         "sourceMappingURL", &sourceMapURL_);
 }
 

js/src/frontend/TokenStream.h

@@ -972,7 +972,7 @@ class MOZ_STACK_CLASS TokenStream
 
     MOZ_MUST_USE bool getDirectives(bool isMultiline, bool shouldWarnDeprecated);
     MOZ_MUST_USE bool getDirective(bool isMultiline, bool shouldWarnDeprecated,
-                                   const char* directive, int directiveLength,
+                                   const char* directive, uint8_t directiveLength,
                                    const char* errorMsgPragma,
                                    UniquePtr<char16_t[], JS::FreePolicy>* destination);
     MOZ_MUST_USE bool getDisplayURL(bool isMultiline, bool shouldWarnDeprecated);
@@ -996,13 +996,13 @@ class MOZ_STACK_CLASS TokenStream
         return true;
     }
 
-    void skipChars(int n) {
-        while (--n >= 0)
+    void skipChars(uint8_t n) {
+        while (n-- > 0)
             getChar();
     }
 
-    void skipCharsIgnoreEOL(int n) {
-        while (--n >= 0)
+    void skipCharsIgnoreEOL(uint8_t n) {
+        while (n-- > 0)
             getCharIgnoreEOL();
     }