gistfile1.diff

diff -r 3790fb70e04c runtime/doc/eval.txt
--- a/runtime/doc/eval.txt	Tue Apr 21 19:10:49 2015 +0200
+++ b/runtime/doc/eval.txt	Mon Apr 27 10:55:34 2015 +0900
@@ -1935,7 +1935,7 @@
 repeat( {expr}, {count})	String	repeat {expr} {count} times
 resolve( {filename})		String	get filename a shortcut points to
 reverse( {list})		List	reverse {list} in-place
-round( {expr})			Float	round off {expr}
+round( {expr} [, {digits}])	Float	round off {expr} with {digits}
 screenattr( {row}, {col})	Number	attribute at screen position
 screenchar( {row}, {col})	Number	character at screen position
 screencol()			Number	current cursor column
@@ -5075,18 +5075,24 @@
 		If you want a list to remain unmodified make a copy first: >
 			:let revlist = reverse(copy(mylist))
 
-round({expr})							*round()*
+round({expr} [, {digits}])				*round()*
 		Round off {expr} to the nearest integral value and return it
 		as a |Float|.  If {expr} lies halfway between two integral
 		values, then use the larger one (away from zero).
 		{expr} must evaluate to a |Float| or a |Number|.
+		If {digits} must evaluate to a |Float| or a |Number|.
+		When the {digits} argument is given then the result should be
+		rounded by number of {digits}. negative value is allowed.
+		value, it works as 
 		Examples: >
 			echo round(0.456)
 <			0.0  >
 			echo round(4.5)
 <			5.0 >
 			echo round(-4.5)
-<			-5.0
+<			-5.0 >
+			echo round(4.583, 2)
+<			-4.58
 		{only available when compiled with the |+float| feature}
 
 screenattr(row, col)						*screenattr()*
diff -r 3790fb70e04c src/eval.c
--- a/src/eval.c	Tue Apr 21 19:10:49 2015 +0200
+++ b/src/eval.c	Mon Apr 27 10:55:34 2015 +0900
@@ -8258,7 +8258,7 @@
     {"resolve",		1, 1, f_resolve},
     {"reverse",		1, 1, f_reverse},
 #ifdef FEAT_FLOAT
-    {"round",		1, 1, f_round},
+    {"round",		1, 2, f_round},
 #endif
     {"screenattr",	2, 2, f_screenattr},
     {"screenchar",	2, 2, f_screenchar},
@@ -16412,11 +16412,19 @@
     typval_T	*rettv;
 {
     float_T	f;
+    int		error = FALSE;
 
     rettv->v_type = VAR_FLOAT;
-    if (get_float_arg(argvars, &f) == OK)
-	rettv->vval.v_float = vim_round(f);
-    else
+    if (get_float_arg(&argvars[0], &f) == OK) {
+	if (argvars[1].v_type != VAR_UNKNOWN) {
+	    long n = get_tv_number_chk(&argvars[1], &error);
+	    if (!error) {
+		float fn = pow(10.0, n);
+		rettv->vval.v_float = vim_round(f * fn) / fn;
+	    }
+	} else
+	    rettv->vval.v_float = vim_round(f);
+    } else
 	rettv->vval.v_float = 0.0;
 }
 #endif
diff -r 3790fb70e04c src/testdir/test65.in
--- a/src/testdir/test65.in	Tue Apr 21 19:10:49 2015 +0200
+++ b/src/testdir/test65.in	Mon Apr 27 10:55:34 2015 +0900
@@ -60,6 +60,11 @@
 :$put =printf('%g', round(0.456))
 :$put =printf('%g', round(4.5))
 :$put =printf('%g', round(-4.50))
+:$put =printf('%g', round(5.127,-1))
+:$put =printf('%g', round(5.127,0))
+:$put =printf('%g', round(5.127,1))
+:$put =printf('%g', round(5.127,2))
+:$put =printf('%g', round(5.127,3))
 :$put ='sqrt'
 :$put =printf('%g', sqrt(100))
 :echo sqrt(-4.01)
diff -r 3790fb70e04c src/testdir/test65.ok
--- a/src/testdir/test65.ok	Tue Apr 21 19:10:49 2015 +0200
+++ b/src/testdir/test65.ok	Mon Apr 27 10:55:34 2015 +0900
@@ -43,6 +43,11 @@
 0.0
 5.0
 -5.0
+10.0
+5.0
+5.1
+5.13
+5.127
 sqrt
 10.0
 str2float