FEAT: Allow CHECKSUM again on strings

implements: metaeducation/rebol-issues#1262

Author: Oldes

src/boot/natives.r

@@ -374,7 +374,7 @@ collect-words: native [
 
 checksum: native [
 	{Computes a checksum, CRC, or hash.}
-	data [binary!] {Bytes to checksum}
+	data [binary! string!] {Bytes to checksum. String value is first converted to UTF-8!}
 	/part length {Length of data}
 	/tcp {Returns an Internet TCP 16-bit checksum}
 	/secure {Returns a cryptographically secure checksum}

src/core/n-strings.c

@@ -194,10 +194,22 @@ static struct digest {
 	REBSER *digest;
 	REBINT sym = SYM_SHA1;
 	REBCNT len;
-	REBYTE *data = VAL_BIN_DATA(arg);
+	REBYTE *data;
 
 	len = Partial1(arg, D_ARG(ARG_CHECKSUM_LENGTH));
 
+	if (IS_STRING(arg)) {
+		// using `digest` just as a temp variable here!
+		digest = Encode_UTF8_Value(arg, len, 0);
+		data = SERIES_DATA(digest);
+		len = SERIES_LEN(digest) - 1;
+	}
+	else {
+		data = VAL_BIN_DATA(arg);
+	}
+
+	
+
 	// Method word:
 	if (D_REF(ARG_CHECKSUM_METHOD)) sym = VAL_WORD_CANON(D_ARG(ARG_CHECKSUM_WORD));
 

src/tests/units/checksum-test.r3

@@ -8,9 +8,21 @@ Rebol [
 
 ~~~start-file~~~ "Checksum"
 
+===start-group=== "Checksum of string"
+	--test-- {checksum of string}
+		--assert #{C000CBCECDCD2582B0418B8CF0301A8E} = checksum/method "ščř" 'md5
+		--assert #{900150983CD24FB0D6963F7D28E17F72} = checksum/method "abc" 'md5
+	--test-- {checksum/part of string}
+		--assert #{900150983CD24FB0D6963F7D28E17F72} = checksum/method/part "abc123" 'md5 3
+		--assert #{900150983CD24FB0D6963F7D28E17F72} = checksum/method/part skip "123abc" 3 'md5 3
+===end-group===
+
+
 ===start-group=== "Checksum with binary key (issue #1910)"
 ;@@ https://github.com/rebol/rebol-issues/issues/1910
 	--test-- "checksum-1"
+		--assert  #{800A1BC1B53CAA795F4DF39DC57652209239E1F1}
+					 = checksum/key "Hello world" "mykey"
 		--assert  #{800A1BC1B53CAA795F4DF39DC57652209239E1F1}
 					 = checksum/key to binary! "Hello world" "mykey"
 		--assert  #{800A1BC1B53CAA795F4DF39DC57652209239E1F1}
@@ -20,6 +32,16 @@ Rebol [
 
 ===start-group=== "Checksum basic"
 	--test-- {checksum ""}
+		str: ""
+		--assert #{da39a3ee5e6b4b0d3255bfef95601890afd80709}
+					= checksum/method str 'sha1
+		--assert #{e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855}
+					= checksum/method str 'sha256
+		--assert #{38b060a751ac96384cd9327eb1b1e36a21fdb71114be07434c0cc7bf63f6e1da274edebfe76f65fbd51ad2f14898b95b}
+					= checksum/method str 'sha384
+		--assert #{cf83e1357eefb8bdf1542850d66d8007d620e4050b5715dc83f4a921d36ce9ce47d0d13c5d85f2b0ff8318d2877eec2f63b931bd47417a81a538327af927da3e}
+					= checksum/method str 'sha512
+	--test-- {checksum #{}}
 		bin: #{}
 		--assert #{da39a3ee5e6b4b0d3255bfef95601890afd80709}
 					= checksum/method bin 'sha1