patch 8.2.5003: cannot do bitwise shiftsv8.2.5003

Problem:    Cannot do bitwise shifts.
Solution:   Add the >> and << operators. (Yegappan Lakshmanan, closes #8457)

11 files changed, 554 insertions, 160 deletions

diff --git a/runtime/doc/eval.txt b/runtime/doc/eval.txt
index 86b9686346..f9443fd297 100644
--- a/runtime/doc/eval.txt
+++ b/runtime/doc/eval.txt
@@ -868,33 +868,36 @@ Expression syntax summary, from least to most significant:
 	expr5 isnot expr5	different |List|, |Dictionary| or |Blob|
 				instance
 
-|expr5|	expr6
-	expr6 +	 expr6 ...	number addition, list or blob concatenation
-	expr6 -	 expr6 ...	number subtraction
-	expr6 .	 expr6 ...	string concatenation
-	expr6 .. expr6 ...	string concatenation
+|expr5|	expr6 << expr6		bitwise left shift
+	expr6 >> expr6		bitwise right shift
 
 |expr6|	expr7
-	expr7 *	 expr7 ...	number multiplication
-	expr7 /	 expr7 ...	number division
-	expr7 %	 expr7 ...	number modulo
+	expr7 +	 expr7 ...	number addition, list or blob concatenation
+	expr7 -	 expr7 ...	number subtraction
+	expr7 .	 expr7 ...	string concatenation
+	expr7 .. expr7 ...	string concatenation
 
 |expr7|	expr8
-	<type>expr8		type check and conversion (|Vim9| only)
+	expr8 *	 expr8 ...	number multiplication
+	expr8 /	 expr8 ...	number division
+	expr8 %	 expr8 ...	number modulo
 
 |expr8|	expr9
-	! expr8			logical NOT
-	- expr8			unary minus
-	+ expr8			unary plus
+	<type>expr9		type check and conversion (|Vim9| only)
 
 |expr9|	expr10
-	expr9[expr1]		byte of a String or item of a |List|
-	expr9[expr1 : expr1]	substring of a String or sublist of a |List|
-	expr9.name		entry in a |Dictionary|
-	expr9(expr1, ...)	function call with |Funcref| variable
-	expr9->name(expr1, ...)	|method| call
-
-|expr10|  number		number constant
+	! expr9			logical NOT
+	- expr9			unary minus
+	+ expr9			unary plus
+
+|expr10|  expr11
+	expr10[expr1]		byte of a String or item of a |List|
+	expr10[expr1 : expr1]	substring of a String or sublist of a |List|
+	expr10.name		entry in a |Dictionary|
+	expr10(expr1, ...)	function call with |Funcref| variable
+	expr10->name(expr1, ...)	|method| call
+
+|expr11|  number		number constant
 	"string"		string constant, backslash is special
 	'string'		string constant, ' is doubled
 	[expr1, ...]		|List|
@@ -1128,14 +1131,26 @@ can be matched like an ordinary character.  Examples:
 	"foo\nbar" =~ "\\n"	evaluates to 0
 
 
-expr5 and expr6				*expr5* *expr6* *E1036* *E1051*
+expr5						*expr5* *bitwise-shift*
+-----
+expr6 << expr6	bitwise left shift				*expr-<<*
+expr6 >> expr6	bitwise right shift				*expr->>*
+							*E1282* *E1283*
+The "<<" and ">>" operators can be used to perform bitwise left or right shift
+of the left operand by the number of bits specified by the right operand.  The
+operands must be positive numbers.  The topmost bit (sign bit) is always
+cleared for ">>".  If the right operand (shift amount) is more than the
+maximum number of bits in a number (|v:numbersize|) the result is zero.
+
+
+expr6 and expr7				*expr6* *expr7* *E1036* *E1051*
 ---------------
-expr6 + expr6   Number addition, |List| or |Blob| concatenation	*expr-+*
-expr6 - expr6   Number subtraction				*expr--*
-expr6 . expr6   String concatenation				*expr-.*
-expr6 .. expr6  String concatenation				*expr-..*
+expr7 + expr7   Number addition, |List| or |Blob| concatenation	*expr-+*
+expr7 - expr7   Number subtraction				*expr--*
+expr7 . expr7   String concatenation				*expr-.*
+expr7 .. expr7  String concatenation				*expr-..*
 
-For |Lists| only "+" is possible and then both expr6 must be a list.  The
+For |Lists| only "+" is possible and then both expr7 must be a list.  The
 result is a new list with the two lists Concatenated.
 
 For String concatenation ".." is preferred, since "." is ambiguous, it is also
@@ -1147,9 +1162,9 @@ In |Vim9| script the arguments of ".." are converted to String for simple
 types: Number, Float, Special and Bool.  For other types |string()| should be
 used.
 
-expr7 * expr7  Number multiplication				*expr-star*
-expr7 / expr7  Number division					*expr-/*
-expr7 % expr7  Number modulo					*expr-%*
+expr8 * expr8  Number multiplication				*expr-star*
+expr8 / expr8  Number division					*expr-/*
+expr8 % expr8  Number modulo					*expr-%*
 
 In legacy script, for all operators except "." and "..", Strings are converted
 to Numbers.
@@ -1191,18 +1206,18 @@ None of these work for |Funcref|s.
 ".", ".." and "%" do not work for Float. *E804* *E1035*
 
 
-expr7							*expr7*
+expr8							*expr8*
 -----
-<type>expr8
+<type>expr9
 
 This is only available in |Vim9| script, see |type-casting|.
 
 
-expr8							*expr8*
+expr9							*expr9*
 -----
-! expr8			logical NOT		*expr-!*
-- expr8			unary minus		*expr-unary--*
-+ expr8			unary plus		*expr-unary-+*
+! expr9			logical NOT		*expr-!*
+- expr9			unary minus		*expr-unary--*
++ expr9			unary plus		*expr-unary-+*
 
 For '!' |TRUE| becomes |FALSE|, |FALSE| becomes |TRUE| (one).
 For '-' the sign of the number is changed.
@@ -1224,21 +1239,21 @@ These three can be repeated and mixed.  Examples:
 	--9	    == 9
 
 
-expr9							*expr9*
------
-This expression is either |expr10| or a sequence of the alternatives below,
+expr10							*expr10*
+------
+This expression is either |expr11| or a sequence of the alternatives below,
 in any order.  E.g., these are all possible:
-	expr9[expr1].name
-	expr9.name[expr1]
-	expr9(expr1, ...)[expr1].name
-	expr9->(expr1, ...)[expr1]
+	expr10[expr1].name
+	expr10.name[expr1]
+	expr10(expr1, ...)[expr1].name
+	expr10->(expr1, ...)[expr1]
 Evaluation is always from left to right.
 
-expr9[expr1]		item of String or |List|	*expr-[]* *E111*
+expr10[expr1]		item of String or |List|	*expr-[]* *E111*
 						*E909* *subscript* *E1062*
 In legacy Vim script:
-If expr9 is a Number or String this results in a String that contains the
-expr1'th single byte from expr9.  expr9 is used as a String (a number is
+If expr10 is a Number or String this results in a String that contains the
+expr1'th single byte from expr10.  expr10 is used as a String (a number is
 automatically converted to a String), expr1 as a Number.  This doesn't
 recognize multibyte encodings, see `byteidx()` for an alternative, or use
 `split()` to turn the string into a list of characters.  Example, to get the
@@ -1246,8 +1261,8 @@ byte under the cursor: >
 	:let c = getline(".")[col(".") - 1]
 
 In |Vim9| script:					*E1147* *E1148*
-If expr9 is a String this results in a String that contains the expr1'th
-single character (including any composing characters) from expr9.  To use byte
+If expr10 is a String this results in a String that contains the expr1'th
+single character (including any composing characters) from expr10.  To use byte
 indexes use |strpart()|.
 
 Index zero gives the first byte or character.  Careful: text column numbers
@@ -1258,7 +1273,7 @@ String.  A negative index always results in an empty string (reason: backward
 compatibility).  Use [-1:] to get the last byte or character.
 In Vim9 script a negative index is used like with a list: count from the end.
 
-If expr9 is a |List| then it results the item at index expr1.  See |list-index|
+If expr10 is a |List| then it results the item at index expr1.  See |list-index|
 for possible index values.  If the index is out of range this results in an
 error.  Example: >
 	:let item = mylist[-1]		" get last item
@@ -1268,14 +1283,14 @@ Generally, if a |List| index is equal to or higher than the length of the
 error.
 
 
-expr9[expr1a : expr1b]	substring or sublist		*expr-[:]*
+expr10[expr1a : expr1b]	substring or sublist		*expr-[:]*
 
-If expr9 is a String this results in the substring with the bytes or
-characters from expr1a to and including expr1b.  expr9 is used as a String,
+If expr10 is a String this results in the substring with the bytes or
+characters from expr1a to and including expr1b.  expr10 is used as a String,
 expr1a and expr1b are used as a Number.
 
 In legacy Vim script the indexes are byte indexes.  This doesn't recognize
-multibyte encodings, see |byteidx()| for computing the indexes.  If expr9 is
+multibyte encodings, see |byteidx()| for computing the indexes.  If expr10 is
 a Number it is first converted to a String.
 
 In Vim9 script the indexes are character indexes and include composing
@@ -1302,20 +1317,20 @@ Examples: >
 	:let s = s[:-3]			" remove last two bytes
 <
 							*slice*
-If expr9 is a |List| this results in a new |List| with the items indicated by
+If expr10 is a |List| this results in a new |List| with the items indicated by
 the indexes expr1a and expr1b.  This works like with a String, as explained
 just above. Also see |sublist| below.  Examples: >
 	:let l = mylist[:3]		" first four items
 	:let l = mylist[4:4]		" List with one item
 	:let l = mylist[:]		" shallow copy of a List
 
-If expr9 is a |Blob| this results in a new |Blob| with the bytes in the
+If expr10 is a |Blob| this results in a new |Blob| with the bytes in the
 indexes expr1a and expr1b, inclusive.  Examples: >
 	:let b = 0zDEADBEEF
 	:let bs = b[1:2]		" 0zADBE
 	:let bs = b[:]			" copy of 0zDEADBEEF
 
-Using expr9[expr1] or expr9[expr1a : expr1b] on a |Funcref| results in an
+Using expr10[expr1] or expr10[expr1a : expr1b] on a |Funcref| results in an
 error.
 
 Watch out for confusion between a namespace and a variable followed by a colon
@@ -1324,11 +1339,11 @@ for a sublist: >
 	mylist[s:]     " uses namespace s:, error!
 
 
-expr9.name		entry in a |Dictionary|		*expr-entry*
+expr10.name		entry in a |Dictionary|		*expr-entry*
 							*E1203* *E1229*
-If expr9 is a |Dictionary| and it is followed by a dot, then the following
+If expr10 is a |Dictionary| and it is followed by a dot, then the following
 name will be used as a key in the |Dictionary|.  This is just like:
-expr9[name].
+expr10[name].
 
 The name must consist of alphanumeric characters, just like a variable name,
 but it may start with a number.  Curly braces cannot be used.
@@ -1345,17 +1360,17 @@ Note that the dot is also used for String concatenation.  To avoid confusion
 always put spaces around the dot for String concatenation.
 
 
-expr9(expr1, ...)	|Funcref| function call  	*E1085*
+expr10(expr1, ...)	|Funcref| function call  	*E1085*
 
-When expr9 is a |Funcref| type variable, invoke the function it refers to.
+When expr10 is a |Funcref| type variable, invoke the function it refers to.
 
 
-expr9->name([args])	method call			*method* *->*
-expr9->{lambda}([args])
+expr10->name([args])	method call			*method* *->*
+expr10->{lambda}([args])
 							*E260* *E276* *E1265*
 For methods that are also available as global functions this is the same as: >
-	name(expr9 [, args])
-There can also be methods specifically for the type of "expr9".
+	name(expr10 [, args])
+There can also be methods specifically for the type of "expr10".
 
 This allows for chaining, passing the value that one method returns to the
 next method: >
@@ -1364,7 +1379,7 @@ next method: >
 Example of using a lambda: >
 	GetPercentage()->{x -> x * 100}()->printf('%d%%')
 <
-When using -> the |expr8| operators will be applied first, thus: >
+When using -> the |expr9| operators will be applied first, thus: >
 	-1.234->string()
 Is equivalent to: >
 	(-1.234)->string()
@@ -1393,7 +1408,7 @@ When using the lambda form there must be no white space between the } and the
 (.
 
 
-							*expr10*
+							*expr11*
 number
 ------
 number			number constant			*expr-number*
diff --git a/src/errors.h b/src/errors.h
index 7a21ceeca8..c819729eb4 100644
--- a/src/errors.h
+++ b/src/errors.h
@@ -3279,3 +3279,9 @@ EXTERN char e_illegal_character_in_word[]
 #endif
 EXTERN char e_atom_engine_must_be_at_start_of_pattern[]
 	INIT(= N_("E1281: Atom '\\%%#=%c' must be at the start of the pattern"));
+#ifdef FEAT_EVAL
+EXTERN char e_bitshift_ops_must_be_number[]
+	INIT(= N_("E1282: bitshift operands must be numbers"));
+EXTERN char e_bitshift_ops_must_be_postive[]
+	INIT(= N_("E1283: bitshift amount must be a positive number"));
+#endif
diff --git a/src/eval.c b/src/eval.c
index ac3c998a51..0ac2dfb358 100644
--- a/src/eval.c
+++ b/src/eval.c
@@ -49,10 +49,11 @@ static int eval2(char_u **arg, typval_T *rettv, evalarg_T *evalarg);
 static int eval3(char_u **arg, typval_T *rettv, evalarg_T *evalarg);
 static int eval4(char_u **arg, typval_T *rettv, evalarg_T *evalarg);
 static int eval5(char_u **arg, typval_T *rettv, evalarg_T *evalarg);
-static int eval6(char_u **arg, typval_T *rettv, evalarg_T *evalarg, int want_string);
-static int eval7t(char_u **arg, typval_T *rettv, evalarg_T *evalarg, int want_string);
+static int eval6(char_u **arg, typval_T *rettv, evalarg_T *evalarg);
 static int eval7(char_u **arg, typval_T *rettv, evalarg_T *evalarg, int want_string);
-static int eval7_leader(typval_T *rettv, int numeric_only, char_u *start_leader, char_u **end_leaderp);
+static int eval8(char_u **arg, typval_T *rettv, evalarg_T *evalarg, int want_string);
+static int eval9(char_u **arg, typval_T *rettv, evalarg_T *evalarg, int want_string);
+static int eval9_leader(typval_T *rettv, int numeric_only, char_u *start_leader, char_u **end_leaderp);
 
 static int free_unref_items(int copyID);
 static char_u *make_expanded_name(char_u *in_start, char_u *expr_start, char_u *expr_end, char_u *in_end);
@@ -638,7 +639,7 @@ deref_function_name(
     char_u	*name = *arg;
 
     ref.v_type = VAR_UNKNOWN;
-    if (eval7(arg, &ref, evalarg, FALSE) == FAIL)
+    if (eval9(arg, &ref, evalarg, FALSE) == FAIL)
     {
 	dictitem_T	*v;
 
@@ -2591,7 +2592,7 @@ eval2(char_u **arg, typval_T *rettv, evalarg_T *evalarg)
     int		getnext;
 
     /*
-     * Get the first variable.
+     * Get the first expression.
      */
     if (eval3(arg, rettv, evalarg) == FAIL)
 	return FAIL;
@@ -2717,7 +2718,7 @@ eval3(char_u **arg, typval_T *rettv, evalarg_T *evalarg)
     int		getnext;
 
     /*
-     * Get the first variable.
+     * Get the first expression.
      */
     if (eval4(arg, rettv, evalarg) == FAIL)
 	return FAIL;
@@ -2856,12 +2857,13 @@ eval4(char_u **arg, typval_T *rettv, evalarg_T *evalarg)
     int		type_is = FALSE;
 
     /*
-     * Get the first variable.
+     * Get the first expression.
      */
     if (eval5(arg, rettv, evalarg) == FAIL)
 	return FAIL;
 
     p = eval_next_non_blank(*arg, evalarg, &getnext);
+
     type = get_compare_type(p, &len, &type_is);
 
     /*
@@ -2991,7 +2993,120 @@ eval_addlist(typval_T *tv1, typval_T *tv2)
 }
 
 /*
- * Handle fourth level expression:
+ * Handle the bitwise left/right shift operator expression:
+ *	var1 << var2
+ *	var1 >> var2
+ *
+ * "arg" must point to the first non-white of the expression.
+ * "arg" is advanced to just after the recognized expression.
+ *
+ * Return OK or FAIL.
+ */
+    static int
+eval5(char_u **arg, typval_T *rettv, evalarg_T *evalarg)
+{
+    /*
+     * Get the first expression.
+     */
+    if (eval6(arg, rettv, evalarg) == FAIL)
+	return FAIL;
+
+    /*
+     * Repeat computing, until no '<<' or '>>' is following.
+     */
+    for (;;)
+    {
+	char_u		*p;
+	int		getnext;
+	exprtype_T	type;
+	int		evaluate;
+	typval_T	var2;
+	int		vim9script;
+
+	p = eval_next_non_blank(*arg, evalarg, &getnext);
+	if (p[0] == '<' && p[1] == '<')
+	    type = EXPR_LSHIFT;
+	else if (p[0] == '>' && p[1] == '>')
+	    type = EXPR_RSHIFT;
+	else
+	    return OK;
+
+	// Handle a bitwise left or right shift operator
+	if (rettv->v_type != VAR_NUMBER)
+	{
+	    // left operand should be a number
+	    emsg(_(e_bitshift_ops_must_be_number));
+	    clear_tv(rettv);
+	    return FAIL;
+	}
+
+	evaluate = evalarg == NULL ? 0 : (evalarg->eval_flags & EVAL_EVALUATE);
+	vim9script = in_vim9script();
+	if (getnext)
+	{
+	    *arg = eval_next_line(*arg, evalarg);
+	    p = *arg;
+	}
+	else if (evaluate && vim9script && !VIM_ISWHITE(**arg))
+	{
+	    error_white_both(*arg, 2);
+	    clear_tv(rettv);
+	    return FAIL;
+	}
+
+	/*
+	 * Get the second variable.
+	 */
+	if (evaluate && vim9script && !IS_WHITE_OR_NUL(p[2]))
+	{
+	    error_white_both(p, 2);
+	    clear_tv(rettv);
+	    return FAIL;
+	}
+	*arg = skipwhite_and_linebreak(p + 2, evalarg);
+	if (eval6(arg, &var2, evalarg) == FAIL)
+	{
+	    clear_tv(rettv);
+	    return FAIL;
+	}
+
+	if (var2.v_type != VAR_NUMBER || var2.vval.v_number < 0)
+	{
+	    // right operand should be a positive number
+	    if (var2.v_type != VAR_NUMBER)
+		emsg(_(e_bitshift_ops_must_be_number));
+	    else
+		emsg(_(e_bitshift_ops_must_be_postive));
+	    clear_tv(rettv);
+	    clear_tv(&var2);
+	    return FAIL;
+	}
+
+	if (evaluate)
+	{
+	    if (var2.vval.v_number > MAX_LSHIFT_BITS)
+		// shifting more bits than we have always results in zero
+		rettv->vval.v_number = 0;
+	    else if (type == EXPR_LSHIFT)
+		rettv->vval.v_number =
+				    rettv->vval.v_number << var2.vval.v_number;
+	    else
+	    {
+		rettv->vval.v_number =
+				    rettv->vval.v_number >> var2.vval.v_number;
+		// clear the topmost sign bit
+		rettv->vval.v_number &= ~((uvarnumber_T)1 << MAX_LSHIFT_BITS);
+	    }
+	}
+
+	clear_tv(&var2);
+    }
+
+    return OK;
+}
+
+/*
+ * Handle fifth level expression:
  *	+	number addition, concatenation of list or blob
  *	-	number subtraction
  *	.	string concatenation (if script version is 1)
@@ -3003,12 +3118,12 @@ eval_addlist(typval_T *tv1, typval_T *tv2)
  * Return OK or FAIL.
  */
     static int
-eval5(char_u **arg, typval_T *rettv, evalarg_T *evalarg)
+eval6(char_u **arg, typval_T *rettv, evalarg_T *evalarg)
 {
     /*
-     * Get the first variable.
+     * Get the first expression.
      */
-    if (eval6(arg, rettv, evalarg, FALSE) == FAIL)
+    if (eval7(arg, rettv, evalarg, FALSE) == FAIL)
 	return FAIL;
 
     /*
@@ -3086,7 +3201,7 @@ eval5(char_u **arg, typval_T *rettv, evalarg_T *evalarg)
 	    return FAIL;
 	}
 	*arg = skipwhite_and_linebreak(*arg + oplen, evalarg);
-	if (eval6(arg, &var2, evalarg, !vim9script && op == '.') == FAIL)
+	if (eval7(arg, &var2, evalarg, !vim9script && op == '.') == FAIL)
 	{
 	    clear_tv(rettv);
 	    return FAIL;
@@ -3221,7 +3336,7 @@ eval5(char_u **arg, typval_T *rettv, evalarg_T *evalarg)
 }
 
 /*
- * Handle fifth level expression:
+ * Handle sixth level expression:
  *	*	number multiplication
  *	/	number division
  *	%	number modulo
@@ -3232,7 +3347,7 @@ eval5(char_u **arg, typval_T *rettv, evalarg_T *evalarg)
  * Return OK or FAIL.
  */
     static int
-eval6(
+eval7(
     char_u	**arg,
     typval_T	*rettv,
     evalarg_T	*evalarg,
@@ -3243,9 +3358,9 @@ eval6(
 #endif
 
     /*
-     * Get the first variable.
+     * Get the first expression.
      */
-    if (eval7t(arg, rettv, evalarg, want_string) == FAIL)
+    if (eval8(arg, rettv, evalarg, want_string) == FAIL)
 	return FAIL;
 
     /*
@@ -3318,7 +3433,7 @@ eval6(
 	    return FAIL;
 	}
 	*arg = skipwhite_and_linebreak(*arg + 1, evalarg);
-	if (eval7t(arg, &var2, evalarg, FALSE) == FAIL)
+	if (eval8(arg, &var2, evalarg, FALSE) == FAIL)
 	    return FAIL;
 
 	if (evaluate)
@@ -3415,7 +3530,7 @@ eval6(
  * Return OK or FAIL.
  */
     static int
-eval7t(
+eval8(
     char_u	**arg,
     typval_T	*rettv,
     evalarg_T	*evalarg,
@@ -3453,7 +3568,7 @@ eval7t(
 	*arg = skipwhite_and_linebreak(*arg, evalarg);
     }
 
-    res = eval7(arg, rettv, evalarg, want_string);
+    res = eval9(arg, rettv, evalarg, want_string);
 
     if (want_type != NULL && evaluate)
     {
@@ -3642,7 +3757,7 @@ handle_predefined(char_u *s, int len, typval_T *rettv)
  * Return OK or FAIL.
  */
     static int
-eval7(
+eval9(
     char_u	**arg,
     typval_T	*rettv,
     evalarg_T	*evalarg,
@@ -3720,7 +3835,7 @@ eval7(
 		// "->" follows.
 		if (ret == OK && evaluate && end_leader > start_leader
 						  && rettv->v_type != VAR_BLOB)
-		    ret = eval7_leader(rettv, TRUE, start_leader, &end_leader);
+		    ret = eval9_leader(rettv, TRUE, start_leader, &end_leader);
 		break;
 
     /*
@@ -3920,19 +4035,19 @@ eval7(
      * Apply logical NOT and unary '-', from right to left, ignore '+'.
      */
     if (ret == OK && evaluate && end_leader > start_leader)
-	ret = eval7_leader(rettv, FALSE, start_leader, &end_leader);
+	ret = eval9_leader(rettv, FALSE, start_leader, &end_leader);
 
     --recurse;
     return ret;
 }
 
 /*
- * Apply the leading "!" and "-" before an eval7 expression to "rettv".
+ * Apply the leading "!" and "-" before an eval9 expression to "rettv".
  * When "numeric_only" is TRUE only handle "+" and "-".
  * Adjusts "end_leaderp" until it is at "start_leader".
  */
     static int
-eval7_leader(
+eval9_leader(
 	typval_T    *rettv,
 	int	    numeric_only,
 	char_u	    *start_leader,
diff --git a/src/structs.h b/src/structs.h
index 612c26cdc1..a367d05811 100644
--- a/src/structs.h
+++ b/src/structs.h
@@ -4152,6 +4152,8 @@ typedef enum
     EXPR_MULT,		// *
     EXPR_DIV,		// /
     EXPR_REM,		// %
+    EXPR_LSHIFT,	// <<
+    EXPR_RSHIFT,	// >>
     // used with ISN_ADDLIST
     EXPR_COPY,		// create new list
     EXPR_APPEND,	// append to first list
diff --git a/src/testdir/test_expr.vim b/src/testdir/test_expr.vim
index 0b6b57e4a2..24daeb6655 100644
--- a/src/testdir/test_expr.vim
+++ b/src/testdir/test_expr.vim
@@ -946,4 +946,66 @@ func Test_string_interp()
   call v9.CheckDefAndScriptSuccess(lines)
 endfunc
 
+" Test for bitwise left and right shift (<< and >>)
+func Test_bitwise_shift()
+  let lines =<< trim END
+    call assert_equal(16, 1 << 4)
+    call assert_equal(2, 16 >> 3)
+    call assert_equal(0, 0 << 2)
+    call assert_equal(0, 0 >> 4)
+    call assert_equal(3, 3 << 0)
+    call assert_equal(3, 3 >> 0)
+    call assert_equal(0, 0 >> 4)
+    call assert_equal(0, 999999 >> 100)
+    call assert_equal(0, 999999 << 100)
+    VAR a = 8
+    VAR b = 2
+    call assert_equal(2, a >> b)
+    call assert_equal(32, a << b)
+    #" operator precedence
+    call assert_equal(48, 1 + 2 << 5 - 1)
+    call assert_equal(3, 8 + 4 >> 4 - 2)
+    call assert_true(1 << 2 < 1 << 3)
+    call assert_true(1 << 4 > 1 << 3)
+    VAR val = 0
+    for i in range(0, v:numbersize - 2)
+        LET val = or(val, 1 << i)
+    endfor
+    call assert_equal(v:numbermax, val)
+    LET val = v:numbermax
+    for i in range(0, v:numbersize - 2)
+        LET val = and(val, invert(1 << i))
+    endfor
+    call assert_equal(0, val)
+    #" multiple operators
+    call assert_equal(16, 1 << 2 << 2)
+    call assert_equal(4, 64 >> 2 >> 2)
+    call assert_true(1 << 2 << 2 == 256 >> 2 >> 2)
+  END
+  call v9.CheckLegacyAndVim9Success(lines)
+
+  call v9.CheckLegacyAndVim9Failure(['VAR v = 2 << -1'], ['E1283:', 'E1283:', 'E1283:'])
+  call v9.CheckLegacyAndVim9Failure(['VAR a = 2', 'VAR b = -1', 'VAR v = a << b'], ['E1283:', 'E1283:', 'E1283:'])
+  call v9.CheckLegacyAndVim9Failure(['VAR v = "8" >> 2'], ['E1282:', 'E1282:', 'E1282:'])
+  call v9.CheckLegacyAndVim9Failure(['VAR v = 1 << "2"'], ['E1282:', 'E1282:', 'E1282:'])
+  call v9.CheckLegacyAndVim9Failure(['VAR a = "8"', 'VAR b = 2', 'VAR v = a << b'], ['E1282:', 'E1012:', 'E1282:'])
+  call v9.CheckLegacyAndVim9Failure(['VAR a = 8', 'VAR b = "2"', 'VAR v = a >> b'], ['E1282:', 'E1012:', 'E1282:'])
+  call v9.CheckLegacyAndVim9Failure(['VAR v = ![] << 1'], ['E745:', 'E1012:', 'E1282:'])
+  call v9.CheckLegacyAndVim9Failure(['VAR v = 1 << ![]'], ['E745:', 'E1012:', 'E1282:'])
+  call v9.CheckLegacyAndVim9Failure(['VAR v = ![] >> 1'], ['E745:', 'E1012:', 'E1282:'])
+  call v9.CheckLegacyAndVim9Failure(['VAR v = 1 >> ![]'], ['E745:', 'E1012:', 'E1282:'])
+  call v9.CheckDefAndScriptFailure(['echo 1<< 2'], ['E1004:', 'E1004:'])
+  call v9.CheckDefAndScriptFailure(['echo 1 <<2'], ['E1004:', 'E1004:'])
+  call v9.CheckDefAndScriptFailure(['echo 1>> 2'], ['E1004:', 'E1004:'])
+  call v9.CheckDefAndScriptFailure(['echo 1 >>2'], ['E1004:', 'E1004:'])
+
+  let lines =<< trim END
+     var a = 1
+             <<
+             4
+     assert_equal(16, a)
+  END
+  call v9.CheckDefAndScriptSuccess(lines)
+endfunc
+
 " vim: shiftwidth=2 sts=2 expandtab
diff --git a/src/testdir/test_vim9_disassemble.vim b/src/testdir/test_vim9_disassemble.vim
index 78604950b9..c1800c3128 100644
--- a/src/testdir/test_vim9_disassemble.vim
+++ b/src/testdir/test_vim9_disassemble.vim
@@ -2864,4 +2864,31 @@ def Test_disassemble_string_interp()
         instr)
 enddef
 
+def BitShift()
+  var a = 1 << 2
+  var b = 8 >> 1
+  var c = a << b
+  var d = b << a
+enddef
+
+def Test_disassemble_bitshift()
+  var instr = execute('disassemble BitShift')
+  assert_match('BitShift\_s*' ..
+               'var a = 1 << 2\_s*' ..
+               '0 STORE 4 in $0\_s*' ..
+               'var b = 8 >> 1\_s*' ..
+               '1 STORE 4 in $1\_s*' ..
+               'var c = a << b\_s*' ..
+               '2 LOAD $0\_s*' ..
+               '3 LOAD $1\_s*' ..
+               '4 OPNR <<\_s*' ..
+               '5 STORE $2\_s*' ..
+               'var d = b << a\_s*' ..
+               '6 LOAD $1\_s*' ..
+               '7 LOAD $0\_s*' ..
+               '8 OPNR <<\_s*' ..
+               '9 STORE $3\_s*' ..
+               '10 RETURN void', instr)
+enddef
+
 " vim: ts=8 sw=2 sts=2 expandtab tw=80 fdm=marker
diff --git a/src/testdir/test_vim9_expr.vim b/src/testdir/test_vim9_expr.vim
index 401ab076b0..df65d72472 100644
--- a/src/testdir/test_vim9_expr.vim
+++ b/src/testdir/test_vim9_expr.vim
@@ -1483,8 +1483,13 @@ func Test_expr4_fails()
   endif
 endfunc
 
+" test bitwise left and right shift operators
+" The tests for this is in test_expr.vim (Test_bitwise_shift)
+" def Test_expr5()
+" enddef
+
 " test addition, subtraction, concatenation
-def Test_expr5()
+def Test_expr6()
   var lines =<< trim END
       assert_equal(66, 60 + 6)
       assert_equal(70, 60 +
@@ -1549,7 +1554,7 @@ def Test_expr5()
   v9.CheckDefAndScriptSuccess(lines)
 enddef
 
-def Test_expr5_vim9script()
+def Test_expr6_vim9script()
   # check line continuation
   var lines =<< trim END
       var name = 11
@@ -1698,7 +1703,7 @@ def Test_expr5_vim9script()
   endfor
 enddef
 
-def Test_expr5_vim9script_channel()
+def Test_expr6_vim9script_channel()
   if !has('channel')
     MissingFeature 'channel'
   else
@@ -1713,7 +1718,7 @@ def Test_expr5_vim9script_channel()
   endif
 enddef
 
-def Test_expr5_float()
+def Test_expr6_float()
   if !has('float')
     MissingFeature 'float'
   else
@@ -1741,7 +1746,7 @@ def Test_expr5_float()
   endif
 enddef
 
-func Test_expr5_fails()
+func Test_expr6_fails()
   let msg = "White space required before and after '+'"
   call v9.CheckDefAndScriptFailure(["var x = 1+2"], msg, 1)
   call v9.CheckDefAndScriptFailure(["var x = 1 +2"], msg, 1)
@@ -1780,14 +1785,14 @@ func Test_expr5_fails()
   call v9.CheckDefAndScriptFailure(['var x = 1 + false'], ['E1051:', 'E1138:'], 1)
 endfunc
 
-func Test_expr5_fails_channel()
+func Test_expr6_fails_channel()
   CheckFeature channel
 
   call v9.CheckDefAndScriptFailure(["var x = 'a' .. test_null_job()"], ['E1105:', 'E908:'], 1)
   call v9.CheckDefAndScriptFailure(["var x = 'a' .. test_null_channel()"], ['E1105:', 'E908:'], 1)
 endfunc
 
-def Test_expr5_list_add()
+def Test_expr6_list_add()
   var lines =<< trim END
       # concatenating two lists with same member types is OK
       var d = {}
@@ -1818,7 +1823,7 @@ def Test_expr5_list_add()
 enddef
 
 " test multiply, divide, modulo
-def Test_expr6()
+def Test_expr7()
   var lines =<< trim END
       assert_equal(36, 6 * 6)
       assert_equal(24, 6 *
@@ -1890,7 +1895,7 @@ def Test_expr6()
   v9.CheckDefExecAndScriptFailure(lines, 'E1154', 2)
 enddef
 
-def Test_expr6_vim9script()
+def Test_expr7_vim9script()
   # check line continuation
   var lines =<< trim END
       var name = 11
@@ -1942,7 +1947,7 @@ def Test_expr6_vim9script()
   v9.CheckDefAndScriptFailure(lines, 'E1004:', 1)
 enddef
 
-def Test_expr6_float()
+def Test_expr7_float()
   if !has('float')
     MissingFeature 'float'
   else
@@ -1975,7 +1980,7 @@ def Test_expr6_float()
   endif
 enddef
 
-func Test_expr6_fails()
+func Test_expr7_fails()
   let msg = "White space required before and after '*'"
   call v9.CheckDefAndScriptFailure(["var x = 1*2"], msg, 1)
   call v9.CheckDefAndScriptFailure(["var x = 1 *2"], msg, 1)
@@ -2019,7 +2024,7 @@ func Test_expr6_fails()
   endfor
 endfunc
 
-func Test_expr6_float_fails()
+func Test_expr7_float_fails()
   CheckFeature float
   call v9.CheckDefAndScriptFailure(["var x = 1.0 % 2"], ['E1035:', 'E804:'], 1)
 endfunc
@@ -2053,7 +2058,7 @@ let g:dict_one = #{one: 1}
 let $TESTVAR = 'testvar'
 
 " type casts
-def Test_expr7()
+def Test_expr8()
   var lines =<< trim END
       var ls: list<string> = ['a', <string>g:string_empty]
       var ln: list<number> = [<number>g:anint, <number>g:thefour]
@@ -2079,7 +2084,7 @@ def Test_expr7()
 enddef
 
 " test low level expression
-def Test_expr8_number()
+def Test_expr9_number()
   # number constant
   var lines =<< trim END
       assert_equal(0, 0)
@@ -2092,7 +2097,7 @@ def Test_expr8_number()
   v9.CheckDefAndScriptSuccess(lines)
 enddef
 
-def Test_expr8_float()
+def Test_expr9_float()
   # float constant
   if !has('float')
     MissingFeature 'float'
@@ -2107,7 +2112,7 @@ def Test_expr8_float()
   endif
 enddef
 
-def Test_expr8_blob()
+def Test_expr9_blob()
   # blob constant
   var lines =<< trim END
       assert_equal(g:blob_empty, 0z)
@@ -2139,7 +2144,7 @@ def Test_expr8_blob()
   v9.CheckDefAndScriptFailure(["var x = 0z123"], 'E973:', 1)
 enddef
 
-def Test_expr8_string()
+def Test_expr9_string()
   # string constant
   var lines =<< trim END
       assert_equal(g:string_empty, '')
@@ -2180,7 +2185,7 @@ def Test_expr8_string()
   v9.CheckDefAndScriptSuccess(lines)
 enddef
 
-def Test_expr8_vimvar()
+def Test_expr9_vimvar()
   v:errors = []
   var errs: list<string> = v:errors
   v9.CheckDefFailure(['var errs: list<number> = v:errors'], 'E1012:')
@@ -2205,7 +2210,7 @@ def Test_expr8_vimvar()
   bwipe!
 enddef
 
-def Test_expr8_special()
+def Test_expr9_special()
   # special constant
   var lines =<< trim END
       assert_equal(g:special_true, true)
@@ -2242,7 +2247,7 @@ def Test_expr8_special()
   v9.CheckDefAndScriptFailure(['v:none = 22'], 'E46:', 1)
 enddef
 
-def Test_expr8_list()
+def Test_expr9_list()
   # list
   var lines =<< trim END
       assert_equal(g:list_empty, [])
@@ -2320,7 +2325,7 @@ def Test_expr8_list()
   v9.CheckDefAndScriptFailure(lines + ['echo numbers[a :b]'], 'E1004:', 4)
 enddef
 
-def Test_expr8_list_vim9script()
+def Test_expr9_list_vim9script()
   var lines =<< trim END
       var l = [
 		11,
@@ -2408,7 +2413,7 @@ def LambdaUsingArg(x: number): func
             x == 2
 enddef
 
-def Test_expr8_lambda()
+def Test_expr9_lambda()
   var lines =<< trim END
       var La = () => 'result'
       # comment
@@ -2494,7 +2499,7 @@ def Test_expr8_lambda()
   v9.CheckDefAndScriptSuccess(lines)
 enddef
 
-def Test_expr8_lambda_block()
+def Test_expr9_lambda_block()
   var lines =<< trim END
       var Func = (s: string): string => {
                       return 'hello ' .. s
@@ -2574,7 +2579,7 @@ def NewLambdaUsingArg(x: number): func
             x == 2
 enddef
 
-def Test_expr8_new_lambda()
+def Test_expr9_new_lambda()
   var lines =<< trim END
       var La = () => 'result'
       assert_equal('result', La())
@@ -2659,7 +2664,7 @@ def Test_expr8_new_lambda()
   v9.CheckDefAndScriptFailure(['var Fx = (a) => [0', ' 1]'], 'E696:', 2)
 enddef
 
-def Test_expr8_lambda_vim9script()
+def Test_expr9_lambda_vim9script()
   var lines =<< trim END
       var v = 10->((a) =>
 	    a
@@ -2678,7 +2683,7 @@ def Test_expr8_lambda_vim9script()
   v9.CheckDefAndScriptSuccess(lines)
 enddef
 
-def Test_expr8funcref()
+def Test_expr9funcref()
   var lines =<< trim END
       def RetNumber(): number
         return 123
@@ -2730,7 +2735,7 @@ enddef
 let g:test_space_dict = {'': 'empty', ' ': 'space'}
 let g:test_hash_dict = #{one: 1, two: 2}
 
-def Test_expr8_dict()
+def Test_expr9_dict()
   # dictionary
   var lines =<< trim END
       assert_equal(g:dic