classify pubkeyhash and scripthash scripts

...both the "in" (ScriptSig) and "out" (ScriptPubkey)

lib/script.js

@@ -188,5 +188,50 @@ Script.prototype.isOpReturn = function() {
   }
 };
 
+Script.prototype.isPubkeyhashOut = function() {
+  if (this.chunks[0] === Opcode('OP_DUP').toNumber()
+    && this.chunks[1] === Opcode('OP_HASH160').toNumber()
+    && this.chunks[2].buf
+    && this.chunks[3] === Opcode('OP_EQUALVERIFY').toNumber()
+    && this.chunks[4] === Opcode('OP_CHECKSIG').toNumber()) {
+    return true;
+  } else {
+    return false;
+  }
+};
+
+Script.prototype.isPubkeyhashIn = function() {
+  if (this.chunks.length === 2
+    && this.chunks[0].buf
+    && this.chunks[1].buf) {
+    return true;
+  } else {
+    return false;
+  }
+};
+
+Script.prototype.isScripthashOut = function() {
+  if (this.chunks.length === 3
+    && this.chunks[0] === Opcode('OP_HASH160').toNumber()
+    && this.chunks[1].buf
+    && this.chunks[1].buf.length === 20
+    && this.chunks[2] === Opcode('OP_EQUAL').toNumber()) {
+    return true;
+  } else {
+    return false;
+  }
+};
+
+//note that these are frequently indistinguishable from pubkeyhashin
+Script.prototype.isScripthashIn = function() {
+  var allpush = this.chunks.every(function(chunk) {
+    return Buffer.isBuffer(chunk.buf);
+  });
+  if (allpush) {
+    return true;
+  } else {
+    return false;
+  }
+};
 
 module.exports = Script;

test/script.js

@@ -216,4 +216,53 @@ describe('Script', function() {
 
   });
 
+  describe('#isPubkeyhashIn', function() {
+    
+    it('should classify this known pubkeyhashin', function() {
+      Script('73 0x3046022100bb3c194a30e460d81d34be0a230179c043a656f67e3c5c8bf47eceae7c4042ee0221008bf54ca11b2985285be0fd7a212873d243e6e73f5fad57e8eb14c4f39728b8c601 65 0x04e365859b3c78a8b7c202412b949ebca58e147dba297be29eee53cd3e1d300a6419bc780cc9aec0dc94ed194e91c8f6433f1b781ee00eac0ead2aae1e8e0712c6').isPubkeyhashIn().should.equal(true);
+    });
+
+    it('should classify this known non-pubkeyhashin', function() {
+      Script('73 0x3046022100bb3c194a30e460d81d34be0a230179c043a656f67e3c5c8bf47eceae7c4042ee0221008bf54ca11b2985285be0fd7a212873d243e6e73f5fad57e8eb14c4f39728b8c601 65 0x04e365859b3c78a8b7c202412b949ebca58e147dba297be29eee53cd3e1d300a6419bc780cc9aec0dc94ed194e91c8f6433f1b781ee00eac0ead2aae1e8e0712c6 OP_CHECKSIG').isPubkeyhashIn().should.equal(false);
+    });
+
+  });
+
+  describe('#isPubkeyhashOut', function() {
+
+    it('should classify this known pubkeyhashout as pubkeyhashout', function() {
+      Script('OP_DUP OP_HASH160 20 0000000000000000000000000000000000000000 OP_EQUALVERIFY OP_CHECKSIG').isPubkeyhashOut().should.equal(true);
+    });
+
+    it('should classify this known non-pubkeyhashout as not pubkeyhashout', function() {
+      Script('OP_DUP OP_HASH160 20 0000000000000000000000000000000000000000').isPubkeyhashOut().should.equal(false)
+    });
+
+  });
+
+  describe('#isScripthashIn', function() {
+    
+    it('should classify this known scripthashin', function() {
+      Script('20 0000000000000000000000000000000000000000').isScripthashIn().should.equal(true);
+    });
+
+    it('should classify this known non-scripthashin', function() {
+      Script('20 0000000000000000000000000000000000000000 OP_CHECKSIG').isScripthashIn().should.equal(false);
+    });
+
+  });
+
+  describe('#isScripthashOut', function() {
+
+    it('should classify this known pubkeyhashout as pubkeyhashout', function() {
+      Script('OP_HASH160 20 0x0000000000000000000000000000000000000000 OP_EQUAL').isScripthashOut().should.equal(true);
+    });
+
+    it('should classify these known non-pubkeyhashout as not pubkeyhashout', function() {
+      Script('OP_HASH160 20 0x0000000000000000000000000000000000000000 OP_EQUAL OP_EQUAL').isScripthashOut().should.equal(false);
+      Script('OP_HASH160 21 0x000000000000000000000000000000000000000000 OP_EQUAL').isScripthashOut().should.equal(false);
+    });
+
+  });
+
 });