patch 8.2.1080: Vim9: no line break allowed in a for loop

Problem:    Vim9: no line break allowed in a for loop.
Solution:   Skip line breaks in for command.

src/eval.c

@@ -38,6 +38,7 @@ typedef struct
 {
     int		fi_semicolon;	// TRUE if ending in '; var]'
     int		fi_varcount;	// nr of variables in the list
+    int		fi_break_count;	// nr of line breaks encountered
     listwatch_T	fi_lw;		// keep an eye on the item used.
     list_T	*fi_list;	// list being used
     int		fi_bi;		// index of blob
@@ -344,6 +345,7 @@ eval_to_string_skip(
     }
     if (skip)
 	--emsg_skip;
+    clear_evalarg(&EVALARG_EVALUATE, eap);
 
     return retval;
 }
@@ -461,6 +463,7 @@ eval_to_string(
 	    retval = vim_strsave(tv_get_string(&tv));
 	clear_tv(&tv);
     }
+    clear_evalarg(&EVALARG_EVALUATE, NULL);
 
     return retval;
 }
@@ -528,6 +531,7 @@ eval_expr(char_u *arg, exarg_T *eap)
     tv = ALLOC_ONE(typval_T);
     if (tv != NULL && eval0(arg, tv, eap, &EVALARG_EVALUATE) == FAIL)
 	VIM_CLEAR(tv);
+    clear_evalarg(&EVALARG_EVALUATE, eap);
 
     return tv;
 }
@@ -675,6 +679,7 @@ eval_foldexpr(char_u *arg, int *cp)
     if (use_sandbox)
 	--sandbox;
     --textwinlock;
+    clear_evalarg(&EVALARG_EVALUATE, NULL);
 
     return (int)retval;
 }
@@ -1481,16 +1486,14 @@ eval_for_line(
     char_u	*arg,
     int		*errp,
     exarg_T	*eap,
-    int		skip)
+    evalarg_T	*evalarg)
 {
     forinfo_T	*fi;
     char_u	*expr;
     typval_T	tv;
     list_T	*l;
-    evalarg_T	evalarg;
+    int		skip = !(evalarg->eval_flags & EVAL_EVALUATE);
 
-    CLEAR_FIELD(evalarg);
-    evalarg.eval_flags = skip ? 0 : EVAL_EVALUATE;
     *errp = TRUE;	// default: there is an error
 
     fi = ALLOC_CLEAR_ONE(forinfo_T);
@@ -1501,8 +1504,9 @@ eval_for_line(
     if (expr == NULL)
 	return fi;
 
-    expr = skipwhite(expr);
-    if (expr[0] != 'i' || expr[1] != 'n' || !VIM_ISWHITE(expr[2]))
+    expr = skipwhite_and_linebreak(expr, evalarg);
+    if (expr[0] != 'i' || expr[1] != 'n'
+				  || !(expr[2] == NUL || VIM_ISWHITE(expr[2])))
     {
 	emsg(_(e_missing_in));
 	return fi;
@@ -1510,7 +1514,8 @@ eval_for_line(
 
     if (skip)
 	++emsg_skip;
-    if (eval0(skipwhite(expr + 2), &tv, eap, &evalarg) == OK)
+    expr = skipwhite_and_linebreak(expr + 2, evalarg);
+    if (eval0(expr, &tv, eap, evalarg) == OK)
     {
 	*errp = FALSE;
 	if (!skip)
@@ -1558,10 +1563,24 @@ eval_for_line(
     }
     if (skip)
 	--emsg_skip;
+    fi->fi_break_count = evalarg->eval_break_count;
 
     return fi;
 }
 
+/*
+ * Used when looping over a :for line, skip the "in expr" part.
+ */
+    void
+skip_for_lines(void *fi_void, evalarg_T *evalarg)
+{
+    forinfo_T	*fi = (forinfo_T *)fi_void;
+    int		i;
+
+    for (i = 0; i < fi->fi_break_count; ++i)
+	eval_next_line(evalarg);
+}
+
 /*
  * Use the first item in a ":for" list.  Advance to the next.
  * Assign the values to the variable (list).  "arg" points to the first one.
@@ -1866,6 +1885,7 @@ eval_next_line(evalarg_T *evalarg)
     char_u	*line;
 
     line = evalarg->eval_getline(0, evalarg->eval_cookie, 0, TRUE);
+    ++evalarg->eval_break_count;
     if (gap->ga_itemsize > 0 && ga_grow(gap, 1) == OK)
     {
 	// Going to concatenate the lines after parsing.
@@ -1898,14 +1918,19 @@ skipwhite_and_linebreak(char_u *arg, evalarg_T *evalarg)
     void
 clear_evalarg(evalarg_T *evalarg, exarg_T *eap)
 {
-    if (evalarg != NULL && eap != NULL && evalarg->eval_tofree != NULL)
+    if (evalarg != NULL && evalarg->eval_tofree != NULL)
     {
-	// We may need to keep the original command line, e.g. for
-	// ":let" it has the variable names.  But we may also need the
-	// new one, "nextcmd" points into it.  Keep both.
-	vim_free(eap->cmdline_tofree);
-	eap->cmdline_tofree = *eap->cmdlinep;
-	*eap->cmdlinep = evalarg->eval_tofree;
+	if (eap != NULL)
+	{
+	    // We may need to keep the original command line, e.g. for
+	    // ":let" it has the variable names.  But we may also need the
+	    // new one, "nextcmd" points into it.  Keep both.
+	    vim_free(eap->cmdline_tofree);
+	    eap->cmdline_tofree = *eap->cmdlinep;
+	    *eap->cmdlinep = evalarg->eval_tofree;
+	}
+	else
+	    vim_free(evalarg->eval_tofree);
 	evalarg->eval_tofree = NULL;
     }
 }
@@ -1961,8 +1986,6 @@ eval0(
     if (eap != NULL)
 	eap->nextcmd = check_nextcmd(p);
 
-    clear_evalarg(evalarg, eap);
-
     return ret;
 }
 

src/ex_eval.c

@@ -899,10 +899,16 @@ ex_eval(exarg_T *eap)
 
     CLEAR_FIELD(evalarg);
     evalarg.eval_flags = eap->skip ? 0 : EVAL_EVALUATE;
-    evalarg.eval_cookie = eap->getline == getsourceline ? eap->cookie : NULL;
+    if (getline_equal(eap->getline, eap->cookie, getsourceline))
+    {
+	evalarg.eval_getline = eap->getline;
+	evalarg.eval_cookie = eap->cookie;
+    }
 
     if (eval0(eap->arg, &tv, eap, &evalarg) == OK)
 	clear_tv(&tv);
+
+    clear_evalarg(&evalarg, eap);
 }
 
 /*
@@ -1108,7 +1114,16 @@ ex_while(exarg_T *eap)
 	}
 	else
 	{
-	    void *fi;
+	    void	*fi;
+	    evalarg_T	evalarg;
+
+	    CLEAR_FIELD(evalarg);
+	    evalarg.eval_flags = skip ? 0 : EVAL_EVALUATE;
+	    if (getline_equal(eap->getline, eap->cookie, getsourceline))
+	    {
+		evalarg.eval_getline = eap->getline;
+		evalarg.eval_cookie = eap->cookie;
+	    }
 
 	    /*
 	     * ":for var in list-expr"
@@ -1119,11 +1134,14 @@ ex_while(exarg_T *eap)
 		// previously evaluated list.
 		fi = cstack->cs_forinfo[cstack->cs_idx];
 		error = FALSE;
+
+		// the "in expr" is not used, skip over it
+		skip_for_lines(fi, &evalarg);
 	    }
 	    else
 	    {
 		// Evaluate the argument and get the info in a structure.
-		fi = eval_for_line(eap->arg, &error, eap, skip);
+		fi = eval_for_line(eap->arg, &error, eap, &evalarg);
 		cstack->cs_forinfo[cstack->cs_idx] = fi;
 	    }
 
@@ -1138,6 +1156,7 @@ ex_while(exarg_T *eap)
 		free_for_info(fi);
 		cstack->cs_forinfo[cstack->cs_idx] = NULL;
 	    }
+	    clear_evalarg(&evalarg, eap);
 	}
 
 	/*

src/globals.h

@@ -1885,7 +1885,7 @@ EXTERN listitem_T range_list_item;
 // Passed to an eval() function to enable evaluation.
 EXTERN evalarg_T EVALARG_EVALUATE
 # ifdef DO_INIT
-	= {EVAL_EVALUATE, NULL, NULL, {0, 0, 0, 0, NULL}, NULL}
+	= {EVAL_EVALUATE, 0, NULL, NULL, {0, 0, 0, 0, NULL}, NULL}
 # endif
 	;
 #endif

src/proto/eval.pro

@@ -22,7 +22,8 @@ int eval_foldexpr(char_u *arg, int *cp);
 char_u *get_lval(char_u *name, typval_T *rettv, lval_T *lp, int unlet, int skip, int flags, int fne_flags);
 void clear_lval(lval_T *lp);
 void set_var_lval(lval_T *lp, char_u *endp, typval_T *rettv, int copy, int flags, char_u *op);
-void *eval_for_line(char_u *arg, int *errp, exarg_T *eap, int skip);
+void *eval_for_line(char_u *arg, int *errp, exarg_T *eap, evalarg_T *evalarg);
+void skip_for_lines(void *fi_void, evalarg_T *evalarg);
 int next_for_item(void *fi_void, char_u *arg);
 void free_for_info(void *fi_void);
 void set_context_for_expression(expand_T *xp, char_u *arg, cmdidx_T cmdidx);

src/structs.h

@@ -1758,11 +1758,12 @@ typedef struct
 // Struct passed through eval() functions.
 // See EVALARG_EVALUATE for a fixed value with eval_flags set to EVAL_EVALUATE.
 typedef struct {
-    int		eval_flags;	// EVAL_ flag values below
+    int		eval_flags;	    // EVAL_ flag values below
+    int		eval_break_count;   // nr of line breaks consumed
 
     // copied from exarg_T when "getline" is "getsourceline". Can be NULL.
     char_u	*(*eval_getline)(int, void *, int, int);
-    void	*eval_cookie;	// argument for eval_getline()
+    void	*eval_cookie;	    // argument for eval_getline()
 
     // Used to collect lines while parsing them, so that they can be
     // concatenated later.  Used when "eval_ga.ga_itemsize" is not zero.

src/testdir/test_vim9_cmd.vim

@@ -160,4 +160,35 @@ def Test_while_linebreak()
   CheckScriptSuccess(lines)
 enddef
 
+def Test_for_linebreak()
+  let lines =<< trim END
+      vim9script
+      let nr = 0
+      for x
+            in
+              [1, 2, 3, 4]
+          nr = nr + x
+      endfor
+      assert_equal(10, nr)
+  END
+  CheckScriptSuccess(lines)
+
+  lines =<< trim END
+      vim9script
+      let nr = 0
+      for x
+            in
+              [1, 2,
+                  3, 4
+                  ]
+          nr = nr
+                 +
+                  x
+      endfor
+      assert_equal(10, nr)
+  END
+  CheckScriptSuccess(lines)
+enddef
+
+
 " vim: ts=8 sw=2 sts=2 expandtab tw=80 fdm=marker

src/userfunc.c

@@ -3825,6 +3825,7 @@ ex_return(exarg_T *eap)
 
     if (eap->skip)
 	--emsg_skip;
+    clear_evalarg(&evalarg, eap);
 }
 
 /*

src/version.c

@@ -754,6 +754,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1080,
 /**/
     1079,
 /**/