FIX: use of escape char ^ must not be allowed in unquoted file notation

resolves: Oldes/Rebol-issues#1442

Author: Oldes

src/core/l-scan.c

@@ -593,7 +593,9 @@
 
 		// Accept ^X encoded char:
 		else if (c == '^') {
-			if (src+1 == end) return 0; // nothing follows ^
+			// checks also if not used in file like: %a^b which must be invalid!
+			if (src+1 == end || (invalid && strchr(cs_cast(invalid), c)))
+				return 0; // nothing follows ^ or used in unquoted file
 			c = Scan_Char(&src);
 			if (!term && IS_WHITE(c)) break;
 			src--;

src/core/l-types.c

@@ -648,7 +648,7 @@ bad_hex:	Trap0(RE_INVALID_CHARS);
 ***********************************************************************/
 {
 	REBUNI term = 0;
-	const REBYTE *invalid = cb_cast(":;()[]\"");
+	const REBYTE *invalid = cb_cast(":;()[]\"^");
 
 	if (*cp == '%') cp++, len--;
 	if (*cp == '"') {

src/tests/units/lexer-test.r3

@@ -82,6 +82,9 @@ Rebol [
 	--test-- "Invalid file"
 	;@@ https://github.com/Oldes/Rebol-issues/issues/1415
 		--assert all [error? e: try [load {%^^}] e/id = 'invalid]
+	;@@ https://github.com/Oldes/Rebol-issues/issues/1442
+		--assert all [error? e: try [load {%a^^b}] e/id = 'invalid]
+		--assert all [error? e: try [load {%a^^ }] e/id = 'invalid]
 
 ===end-group===
 

src/tests/units/mold-test.r3

@@ -213,6 +213,9 @@ Rebol [
 		]
 		;@@ https://github.com/Oldes/Rebol-issues/issues/1415
 		--assert "%%5E" == mold to-file "^^"
+		;@@ https://github.com/Oldes/Rebol-issues/issues/1442
+		--assert "%a%02c" == mold to-file "a^Bc"
+		--assert "%a%20b" == mold to-file "a^ b"
 
 ===end-group===