buffer: allow encoding param to collapse

Currently the signature is indexOf(val[, byteOffset[, encoding]]) Instead allow indexOf(val[, byteOffset][, encoding]) so that byteOffset does not need to be passed. PR-URL: #4803 Reviewed-By: James M Snell <[email protected]>

Author: trevnorris

lib/buffer.js

@@ -477,10 +477,14 @@ function slowIndexOf(buffer, val, byteOffset, encoding){
 }
 
 Buffer.prototype.indexOf=functionindexOf(val,byteOffset,encoding){
-if(byteOffset>0x7fffffff)
+if(typeofbyteOffset==='string'){
+encoding=byteOffset;
+byteOffset=0;
+}elseif(byteOffset>0x7fffffff){
 byteOffset=0x7fffffff;
-elseif(byteOffset<-0x80000000)
+}elseif(byteOffset<-0x80000000){
 byteOffset=-0x80000000;
+}
 byteOffset>>=0;
 
 if(typeofval==='string'){

test/parallel/test-buffer-indexof.js

@@ -111,6 +111,11 @@ assert.equal(
 .indexOf(Buffer('d','binary'),0,'binary'),3);
 
 
+// test optional offset with passed encoding
+assert.equal(newBuffer('aaaa0').indexOf('30','hex'),4);
+assert.equal(newBuffer('aaaa00a').indexOf('3030','hex'),4);
+
+
 // test usc2 encoding
 vartwoByteString=newBuffer('\u039a\u0391\u03a3\u03a3\u0395','ucs2');