Oberon/A2/Oberon.RFC3986.Mod

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(* ETH Oberon, Copyright 1990-2006 Computer Systems Institute, ETH Zurich, CH-8092 Zurich.
Desktops.OpenDoc http://www.oberon.ethz.ch/ and follow the "license agreement" link. *)

MODULE RFC3986 IN Oberon;	(** portable *)

(*  Desktops.OpenDoc  http://www.apps.ietf.org/rfc/rfc3986.html .
https://en.wikipedia.org/wiki/Percent-encoding
Based upon procedures in HyperDocs.Mod of ETH Oberon / PC Native 05.01.2003.

The source and target parameters of exported procedures are strings.  
A source string lacking a 0X string termination is rejected.  ple 2005-09-07*)

IMPORT SYSTEM, Texts, Oberon, Strings;

CONST 
	hexdigits = "0123456789ABCDEF";

VAR
	errors*: SHORTINT; (* Error counter *)
	W: Texts.Writer;
	hexdigitsarray: ARRAY 17 OF CHAR;
  
	PROCEDURE Log(ch: CHAR);
	BEGIN Texts.Write(W, ch) END Log;
	    
	PROCEDURE LogLn;
	BEGIN Texts.WriteLn(W) END LogLn;
	    
	(* Precondition = string ends with 0X *)
	PROCEDURE LogString(s: ARRAY OF CHAR);
	BEGIN Texts.WriteString(W, s) END LogString;
	    
	(* Precondition: s contains characters and possibly 0X. 
	If 0X is present, stop the output there. *)
	PROCEDURE LogChars(s: ARRAY OF CHAR);
	VAR i: LONGINT;
	BEGIN
		i := 0;
    	WHILE (i < LEN(s)) & (s[i] # 0X) DO Texts.Write(W, s[i]); INC(i) END;
	 END LogChars;
	    
	(* PROCEDURE LogInt(x, n: LONGINT);
	BEGIN Texts.WriteInt(W, x, n) END LogInt; *)
	    
	PROCEDURE LogAppend;
	BEGIN Texts.Append(Oberon.Log, W.buf) END LogAppend;
	    
	PROCEDURE HexVal(ch: CHAR): INTEGER;
	BEGIN
		(* LogString("RFC3986.HexVal: invoked on ch = "); Log(22X); Log(ch); 
		Log(22X); LogString("."); LogLn; *)

		(* We might hope that an application of CAP would remove the 
		need for the case of ch in a..z but CAP does not check the parameter.  
		Thus CAP("A") and CAP("2") shift characters which should not be 
		shifted. *)
		(* ch := CAP(ch); *)

		(* LogString("CAP(ch) = "); Log(HexDigit(ORD(ch) DIV 16));
		Log(HexDigit(ORD(ch) MOD 16)); LogString("X."); LogLn; *)
		IF (ch >= "0") & (ch <= "9") THEN
			RETURN ORD(ch)-ORD("0")
		ELSIF (ch >= "A") & (ch <= "F") THEN
			RETURN ORD(ch)-ORD("A")+10
		ELSIF (ch >= "a") & (ch <= "f") THEN
			RETURN ORD(ch)-ORD("a")+10
		ELSE
			LogString("RFC3986.HexVal: invoked on illegal character."); LogLn;
			RETURN 0
		END
	END HexVal;

	PROCEDURE HexDigit(i: INTEGER): CHAR;
	BEGIN
		RETURN hexdigitsarray[i];
	(*	IF i < 10 THEN
			RETURN CHR(i+ORD("0"))
		ELSE
			RETURN CHR(i-10+ORD("A"))
		END *)
	END HexDigit;

(** Escape codes are literalized or contracted.  
	E.g. "Hello%20World" becomes "Hello World". *)
PROCEDURE Decode*(VAR source, target: ARRAY OF CHAR);
VAR 
	is, it, slen, tlen: LONGINT;
	ch: CHAR;
BEGIN
	errors := 0;
	is := 0; it := 0; slen := LEN(source); tlen := LEN(target);
	IF SYSTEM.ADR(source[0]) = SYSTEM.ADR(target[0]) THEN
	(* Aiming to put the literal version where the source exists.  The literal 
	version is never larger than the escaped version.  Array overflow is 
	impossible but check for presence of 0X. *)
		LOOP
			IF is = slen THEN (* 0X absent. *) 
				INC(errors);
				LogString("RFC3986.Decode: 0X absent from "); LogLn;
				LogString("source character array.  Not literalizing."); LogLn;
				RETURN
			ELSIF source[is] = 0X THEN EXIT
			ELSE INC(is);
			END
		END;
		(* Now literalize. *)
		is := 0;
		LOOP
			ch := source[is];
			IF ch = 0X THEN target[it] := 0X; EXIT
			ELSIF (ch = "%") & ((is+2) < slen) THEN
				IF Strings.IsHexDigit(source[is+1]) & Strings.IsHexDigit(source[is+2]) 
					THEN (* have a valid encoding such as %3d *)
					target[it] := CHR(16*HexVal(source[is+1])+HexVal(source[is+2]));
					INC(is); INC(is)
				ELSE target[it] := ch; (* = "%" *)
				END
			ELSE target[it] := ch (* <> "%" *)
			END;
			INC(is); INC(it)
		END
	ELSE (* Source and target are distinct.  Count characters to check 
		whether the literalized string will fit in the target array. *)
		LOOP
			IF is = slen THEN (* 0X absent. *) 
				INC(errors);
				LogString("RFC3986.Decode: 0X absent from "); LogLn;
				LogString("source character array.  Not literalizing."); LogLn;
				RETURN
			ELSIF source[is] = 0X THEN EXIT
			ELSIF (source[is] = "%") & ((is+2) < slen) THEN
				IF Strings.IsHexDigit(source[is+1]) & Strings.IsHexDigit(source[is+2])
					THEN (* have a valid encoding such as %3d *) INC(is, 2);
				(* ELSE in all other cases, source[is..(is+2)] = "%GG" for example, 
						source[is] = "%" is left as literal. *)
				END
			END;
			INC(is); INC(it)
		END;
		(* Index it now locates the terminal character of the hypothetical 
		literalized string. *)
		IF it >= tlen THEN (* literalized string is too long for the target array. *)
			INC(errors);
			LogString("RFC3986.Decode: literalized string "); LogLn;
			LogString("will be too long for the target "); LogLn;
			LogString("array.  Not literalizing."); LogLn;
			RETURN
		END;
		is := 0; it := 0;
		LOOP
			ch := source[is];
			IF (ch = "%") & ((is+2) < slen) THEN
				IF Strings.IsHexDigit(source[is+1]) & Strings.IsHexDigit(source[is+2])
					THEN (* have a valid encoding such as %3d *) 
					target[it] := CHR(16*HexVal(source[is+1])+HexVal(source[is+2]));
					INC(is, 2)
				ELSE target[it] := ch (* = "%" *)
				END
			ELSE target[it] := ch (* <> "%" *)
			END;
			IF target[it] = 0X THEN EXIT END;
			INC(is); INC(it)
		END
	END
END Decode;

(** All special characters in source are escaped according to RFC 2396. E.g. 
"a+b" becomes "a%2Bb".  Special characters are: 1X .. 20X, "+", "&", "=", 
"?", "%", "$", ";". "#", ":" & special. 
  
Escaping a character makes the string longer.  Overflow of the character 
array is avoided.

Two procedures Encode1 and Encode2 follow.  This Encode is a wrapper which can 
invoke either of them according to choice of the user. *)
PROCEDURE Encode*(VAR source, target: ARRAY OF CHAR; special: CHAR);

PROCEDURE RequiresEscape(ch:CHAR):BOOLEAN;
BEGIN
	IF (ch = 0X)
	THEN 
		RETURN(FALSE)
	ELSIF (ch <= 020X) OR (ch = "+") OR (ch = "&") OR (ch = "=") OR (ch = "?") 
		OR (ch = "%") OR (ch = "$") OR (ch = ";") OR (ch = "#") OR (ch = ":") 
		OR (ch = special) 
	THEN
		RETURN(TRUE)
	ELSE 
		RETURN(FALSE) 
	END
END RequiresEscape;

(** The source and target parameters can refer to one or two 
actual parameters.  With one actual parameter, the string is escaped 
"in place".  With two actual parameters, the source parameter is untouched. *)
PROCEDURE Encode1(VAR source, target: ARRAY OF CHAR; special: CHAR);
VAR
	is, it, slen, tlen: LONGINT;
	ch: CHAR;

BEGIN
	errors := 0;
	is := 0; it := 0; slen := LEN(source); tlen := LEN(target);
	LOOP
		IF is = slen THEN (* 0X absent. *) 
			DEC(is); DEC(it); INC(errors);
			LogString("RFC3986.Encode.Encode1: 0X absent from "); LogLn;
			LogString("character array.  Not escaping."); LogLn;
			RETURN
		ELSIF source[is] = 0X THEN EXIT
		ELSIF RequiresEscape(source[is]) THEN INC(it, 3); INC(is)
		ELSE INC(it); INC(is)
		END
	END;
	(* is now contains the index of the last character of the string; 
	"it" contains the index of the last character in the escaped version
	and may be >= tlen.  The source string ends with 0X. *)
	IF it >= tlen THEN (* The escaped version is too long for the target array. *)
		INC(errors);
		LogString("RFC3986.Encode.Encode1: Escaped version of string "); LogLn;
		Log(22X); LogString(source); Log(22X); LogLn;
		LogString("will be too long for the array.  Not escaping."); LogLn;
		RETURN
	END;
	IF SYSTEM.ADR(source[0]) = SYSTEM.ADR(target[0]) THEN
		(* Aiming to put the escaped version where the source exists.
		Put the translated characters into the tail end of the array.  
		After translation is complete, shift the string up to the front of the array.  
		This avoids shifting the downstream characters for each character which 
		needs escaping. *)
		it := tlen-1;
		IF source[is] = 0X THEN target[it] := 0X; DEC(is); DEC(it) 
		ELSE
			INC(errors);
			LogString("RFC3986.Encode1: index of terminus of source string"); LogLn;
			LogString("not located properly.  Not escaping."); LogLn;
			RETURN
		END;
		(* Proceed to check characters from the terminus towards the origin of 
		the array; escape as required. *)
		LOOP
			IF is = -1 THEN (* finished source array *) EXIT END;
			ch := source[is];
			IF RequiresEscape(ch) THEN
				target[it] := HexDigit(ORD(ch) MOD 16); DEC(it);
				target[it] := HexDigit(ORD(ch) DIV 16); DEC(it);
				target[it] := "%";  DEC(it)
			ELSE (* just copy the character *)
				target[it] := ch; DEC(it)
			END;
			DEC(is)
		END;
		(* Encoding finished; shift the string to the origin of the array. *)
		is := 0; INC(it);
		LOOP
			IF it = tlen THEN EXIT END;
			target[is] := target[it]; 
			IF target[it] = 0X THEN EXIT END;
			INC(is); INC(it);
		END
	ELSE (* source and target are in distinct arrays.  In this case work 
		from the head toward the tail. *)
		is := 0; it := 0;
		LOOP
			IF is = slen THEN (* end of source array *) RETURN END;
			(* check the character and translate if required; *)
			IF RequiresEscape(source[is]) THEN
				target[it] := "%";  INC(it);
				target[it] := HexDigit(ORD(source[is]) DIV 16); INC(it);
				target[it] := HexDigit(ORD(source[is]) MOD 16);INC(it)
			ELSE (* just copy the character; *)
				target[it] := source[is]; INC(it);
			END;
			IF source[is] = 0X THEN (* End of string; finished. *) EXIT END;
			INC(is)
		END; (* Loop over source characters. *)
	END; (* Cases of single and distinct arrays for source and target. *)
	RETURN
END Encode1;

(** The source and target parameters can refer to one or two 
actual parameters.  In this procedure an intermediate array is created to put 
the escaped array into.  After escaping, the intermediate array is copied to 
the target. *)
PROCEDURE Encode2(VAR source, target: ARRAY OF CHAR; special: CHAR);
VAR
	is, it, slen, tlen: LONGINT;
	(* ch: CHAR; *)
	intermediate: POINTER TO ARRAY OF CHAR;

BEGIN
	errors := 0;
	is := 0; it := 0; slen := LEN(source); tlen := LEN(target);
	LOOP
		IF is = slen THEN (* 0X absent. *) 
			DEC(is); DEC(it); INC(errors);
			LogString("RFC3986.Encode.Encode2: 0X absent from character array."); LogLn;
			RETURN
		ELSIF source[is] = 0X THEN EXIT
		ELSIF RequiresEscape(source[is]) THEN INC(it, 3); INC(is)
		ELSE INC(it); INC(is)
		END
	END;
	(* is now contains the index of the last character of the string; 
	"it" contains the index of the last character in the escaped version 
	and may be >= tlen.  The source string ends with 0X. *)
	IF it >= tlen THEN (* The escaped version is too long for the target array. *)
		INC(errors);
		LogString("RFC3986.Encode.Encode2: Escaped version of string "); LogLn;
		Log(22X); LogString(source); Log(22X); LogLn;
		LogString("will be too large for the array.  Not escaping."); LogLn;
		RETURN
	END;
	NEW(intermediate, it+1);
	is := 0; it := 0;
	LOOP
		IF is = slen THEN (* end of source array *) EXIT END;
		(* check the character and translate if required; *)
		IF RequiresEscape(source[is]) THEN
			intermediate[it] := "%";  INC(it);
			intermediate[it] := HexDigit(ORD(source[is]) DIV 16); INC(it);
			intermediate[it] := HexDigit(ORD(source[is]) MOD 16);INC(it)
		ELSE 
			intermediate[it] := source[is];  INC(it);
			(* LogChars("intermediate = "); LogChars(intermediate^); LogLn; *)
		END;
		IF source[is] = 0X THEN (* end of string *) EXIT END;
		INC(is);
	END; (* Loop over characters. *)
	(* The escaped string is now in intermediate^.  Copy intermediate to 
	target. *)
	(* (LogString("intermediate = "); 
	Log(22X); LogChars(intermediate^);  Log(22X); LogLn; *)
	it := 0;
	LOOP
		IF it = tlen THEN 
			INC(errors);
			LogString("RFC3986.Encode.Encode2: 0X not found at end of target string."); LogLn;
		EXIT 
		END;
		target[it] := intermediate[it];
		IF target[it] = 0X THEN EXIT END;
		INC(it)
	END
END Encode2;

BEGIN
	Encode1(source, target, special)
END Encode;

PROCEDURE Test*;
VAR 
	source5, intermediate5, target5: ARRAY 5 OF CHAR;
	source6, intermediate6 (*, target6*) : ARRAY 6 OF CHAR;
	source7, intermediate7, target7: ARRAY 7 OF CHAR;
	source8, intermediate8 (*, target8*) : ARRAY 8 OF CHAR;
BEGIN
	LogString("RFC3986.Test: begun."); LogLn;
	LogLn;
	LogString("Test with distinct source and target locations."); LogLn;

	intermediate7 := "%GGlah"; (* Anomalous case suggested by Jan Verhoeven. *)
	target7 := "------"; LogLn;
	LogString("intermediate7 = "); Log(22X); LogChars(intermediate7);  Log(22X); LogLn;
	LogString("target7 = "); Log(22X); LogChars(target7); Log(22X); LogLn; 
	LogString("Invoke Decode(intermediate7, target7)."); LogLn;
	Decode(intermediate7, target7);
	LogString("target7 = "); Log(22X); LogChars(target7); Log(22X); LogLn; 
	LogLn;
	LogAppend;

	LogLn;
	source5 := "blah";
	intermediate5 := "----"; 
	target5 := "----"; 
	LogString("source5 = "); Log(22X);  LogChars(source5);  Log(22X); LogLn;
	LogString("intermediate5 = "); Log(22X); LogChars(intermediate5);  Log(22X); LogLn;
	LogString("target5 = "); Log(22X); LogChars(target5); Log(22X); LogLn; 
	LogString("Invoke Encode(source5, intermediate5, ..."); LogLn;
	Encode(source5, intermediate5, " ");
	LogString("intermediate5 = "); Log(22X); LogChars(intermediate5); Log(22X); LogLn; 
	LogString("Invoke Decode(intermediate5, target5)."); LogLn;
	Decode(intermediate5, target5);
	LogString("target5 = "); Log(22X); LogChars(target5); Log(22X); LogLn; 
	LogLn;
	LogAppend;
	
	source5 := "blah"; source5[4] := 73X; 
	intermediate5 := "----"; intermediate5[4] := 2DX;
	target5 := "----"; 
	LogString("source5 = "); Log(22X);  LogChars(source5);  Log(22X); LogLn;
	LogString("intermediate5 = "); Log(22X); LogChars(intermediate5);  Log(22X); LogLn;
	LogString("target5 = "); Log(22X); LogChars(target5); Log(22X); LogLn; 
	LogString("Invoke Encode(source5, intermediate5, ..."); LogLn;
	Encode(source5, intermediate5, " ");
	LogString("intermediate5 = "); Log(22X); LogChars(intermediate5); Log(22X); LogLn; 
	LogString("Invoke Decode.(intermediate5, target5)"); LogLn;
	Decode(intermediate5, target5);
	LogString("target5 = "); Log(22X); LogChars(target5); Log(22X); LogLn; 
	LogLn;
	LogAppend;
	
	source5 := "+lah";
	intermediate7 := "------"; 
	target5 := "----"; 
	LogString("source5 = "); Log(22X);  LogChars(source5);  Log(22X); LogLn;
	LogString("intermediate7 = "); Log(22X); LogChars(intermediate7);  Log(22X); LogLn;
	LogString("target5 = "); Log(22X); LogChars(target5); Log(22X); LogLn; 
	LogString("Invoke Encode(source5, intermediate7, ..."); LogLn;
	Encode(source5, intermediate7, " ");
	LogString("intermediate7 = "); Log(22X); LogChars(intermediate7); Log(22X); LogLn;
	LogString("Invoke Decode(intermediate7, target5)."); LogLn;
	Decode(intermediate7, target5);
	LogString("target5 = "); Log(22X); LogChars(target5); Log(22X); LogLn; 
	LogLn;
	LogAppend;

	source5 := "bla+";
	intermediate6 := "-----";
	LogString("source5 = "); Log(22X);  LogChars(source5);  Log(22X); LogLn;
	LogString("intermediate6 = "); Log(22X); LogChars(intermediate6);  Log(22X); LogLn;
	LogString("Invoke Encode(source5, intermediate6, ..."); LogLn;
	Encode(source5, intermediate6, " ");
	LogString("intermediate6 = "); Log(22X); LogChars(intermediate6); Log(22X); LogLn;
	LogLn;
	LogAppend;

	source5 := "bla+";
	intermediate7 := "------"; 
	target5 := "----"; 
	LogString("source5 = "); Log(22X);  LogChars(source5);  Log(22X); LogLn;
	LogString("intermediate7 = "); Log(22X); LogChars(intermediate7);  Log(22X); LogLn;
	LogString("target5 = "); Log(22X); LogChars(target5); Log(22X); LogLn; 
	LogString("Invoke Encode(source5, intermediate7, ..."); LogLn;
	Encode(source5, intermediate7, " ");
	LogString("intermediate7 = "); Log(22X); LogChars(intermediate7); Log(22X);LogLn; 
	LogString("Invoke Decode(intermediate7, target5)."); LogLn;
	Decode(intermediate7, target5);
	LogString("target5 = "); Log(22X); LogChars(target5); Log(22X); LogLn; 
	LogLn;
	LogAppend;

	source8 := "bla+";
	intermediate8 := "-------";
	target5 := "----"; 
	LogString("source8 = "); Log(22X);  LogChars(source8);  Log(22X); LogLn;
	LogString("intermediate8 = "); Log(22X); LogChars(intermediate8);  Log(22X); LogLn;
	LogString("target5 = "); Log(22X);  LogChars(target5);  Log(22X); LogLn;
	LogString("Invoke Encode(source8, intermediate8, ..."); LogLn;
	Encode(source8, intermediate8, " ");
	LogString("intermediate8 = "); Log(22X); LogChars(intermediate8); Log(22X); LogLn;
	LogString("Invoke Decode(intermediate8, target5)."); LogLn;
	Decode(intermediate8, target5);
	LogString("target5 = "); Log(22X); LogChars(target5); Log(22X); LogLn; 
	LogLn;
	LogAppend;

	LogString("Now test with coincident source and target locations."); LogLn;
	LogLn;
	
	intermediate7 := "%GGlah"; (* Anomalous case suggested by Jan Verhoeven. *)
	LogString("intermediate7 = "); Log(22X); LogChars(intermediate7);  Log(22X); LogLn;
	LogString("Invoke Decode(intermediate7, intermediate7)."); LogLn;
	Decode(intermediate7, intermediate7);
	LogString("intermediate7 = "); Log(22X); LogChars(intermediate7); Log(22X); LogLn; 
	LogLn;
	LogAppend;

	source5 := "blah";
	LogString("source5 = "); Log(22X);  LogChars(source5);  Log(22X); LogLn;
	LogString("Invoke Encode(source5, source5, ..."); LogLn;
	Encode(source5, source5, " ");
	LogString("source5 = "); Log(22X); LogChars(source5); Log(22X); LogLn; 
	LogString("Invoke Decode(source5, source5)."); LogLn;
	Decode(source5, source5);
	LogString("source5 = "); Log(22X); LogChars(source5); Log(22X); LogLn; 
	LogLn;
	LogAppend;
	
	source5 := "blah"; source5[4] := 73X;
	LogString("source5 = "); Log(22X);  LogChars(source5);  Log(22X); LogLn;
	LogString("Invoke Encode(source5, source5, ..."); LogLn;
	Encode(source5, source5, " ");
	LogString("source5 = "); Log(22X); LogChars(source5); Log(22X); LogLn; 
	LogString("Invoke Decode(source5, source5)."); LogLn;
	Decode(source5, source5);
	LogString("source5 = "); Log(22X); LogChars(source5); Log(22X); LogLn; 
	LogLn;
	LogAppend;
	
	source5 := "+lah";
	LogString("source5 = "); Log(22X);  LogChars(source5);  Log(22X); LogLn;
	LogString("Invoke Encode(source5, source5, ..."); LogLn;
	Encode(source5, source5, " ");
	LogString("source5 = "); Log(22X); LogChars(source5); Log(22X); LogLn; 
	LogString("Invoke Decode(source5, source5)."); LogLn;
	Decode(source5, source5);
	LogString("source5 = "); Log(22X); LogChars(source5); Log(22X); LogLn; 
	LogLn;
	LogAppend;
	
	source6 := "+lah";
	LogString("source6 = "); Log(22X);  LogChars(source6);  Log(22X); LogLn;
	LogString("Invoke Encode(source6, source6, ..."); LogLn;
	Encode(source6, source6, " ");
	LogString("source6 = "); Log(22X); LogChars(source6); Log(22X); LogLn; 
	LogString("Invoke Decode(source6, source6)."); LogLn;
	Decode(source6, source6);
	LogString("source6 = "); Log(22X); LogChars(source6); Log(22X); LogLn; 
	LogLn;
	LogAppend;
	
	source7 := "+lah";
	LogString("source7 = "); Log(22X);  LogChars(source7);  Log(22X); LogLn;
	LogString("Invoke Encode(source7, source7, ..."); LogLn;
	Encode(source7, source7, " ");
	LogString("source7 = "); Log(22X); LogChars(source7); Log(22X); LogLn;
	LogAppend;
	LogString("Invoke Decode(source7, source7)."); LogLn;
	LogAppend;
	Decode(source7, source7);
	LogString("source7 = "); Log(22X); LogChars(source7); Log(22X); LogLn; 
	LogLn;
	LogAppend;
	
	source5 := "bla+";
	LogString("source5 = "); Log(22X);  LogChars(source5);  Log(22X); LogLn;
	LogString("Invoke Encode(source5, source5, ..."); LogLn;
	Encode(source5, source5, " ");
	LogString("source5 = "); Log(22X); LogChars(source5); Log(22X); LogLn;
	LogString("Invoke Decode(source5, source5)."); LogLn;
	Decode(source5, source5);
	LogString("source5 = "); Log(22X); LogChars(source5); Log(22X); LogLn; 
	LogLn;
	LogAppend;
	
	source6 := "bla+";
	LogString("source6 = "); Log(22X);  LogChars(source6);  Log(22X); LogLn;
	LogString("Invoke Encode(source6, source6, ..."); LogLn;
	Encode(source6, source6, " ");
	LogString("source6 = "); Log(22X); LogChars(source6); Log(22X); LogLn;
	LogString("Invoke Decode(source6, source6)."); LogLn;
	Decode(source6, source6);
	LogString("source6 = "); Log(22X); LogChars(source6); Log(22X); LogLn; 
	LogLn;
	LogAppend;
	
	source7 := "bla+";
	LogString("source7 = "); Log(22X);  LogChars(source7);  Log(22X); LogLn;
	LogString("Invoke Encode(source7, source7, ..."); LogLn;
	Encode(source7, source7, " ");
	LogString("source7 = "); Log(22X); LogChars(source7); Log(22X); LogLn; 
	LogString("Invoke Decode(source7, source7)."); LogLn;
	Decode(source7, source7);
	LogString("source7 = "); Log(22X); LogChars(source7); Log(22X); LogLn;
	LogLn;
	LogAppend;
	
	source8 := "bla+";
	LogString("source8 = "); Log(22X);  LogChars(source8);  Log(22X); LogLn;
	LogString("Invoke Encode(source8, source8, ..."); LogLn;
	Encode(source8, source8, " ");
	LogString("source8 = "); Log(22X); LogChars(source8); Log(22X); LogLn;
	LogString("Invoke Decode(source8, source8)."); LogLn;
	Decode(source8, source8);
	LogString("source8 = "); Log(22X); LogChars(source8); Log(22X); LogLn; 
	LogLn;
	LogAppend; (**)
	
	LogString("RFC3986.Test: completed.");  LogLn;
	LogAppend
END Test;

BEGIN
	Texts.OpenWriter(W);
	hexdigitsarray := hexdigits;
END RFC3986.

RFC3986.Test