vi: allow motion count for change/delete/yank/shift

The motion that determines the range of a change, delete, yank
or shift operation can have its own count.  Thus the commands
'5dd' and 'd5d' are equivalent:  both delete 5 lines.

When the command itself also has a count the two values are
multiplied.  Thus the command '2d3w' deletes 6 words and '2D3G'
deletes from the current line to line 6.

(When dealing with structured data it might make sense to think in
units of 3 words so '2d3w' is deleting 2 such units.  It doesn't
seem quite as sensible to express 'delete from current line to line 6'
as '2D3G' but vi permits it.)

function                                             old     new   delta
get_motion_char                                        -      68     +68
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 0/0 up/down: 68/0)               Total: 68 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 18 insertions, 2 deletions

diff --git a/editors/vi.c b/editors/vi.c
index 5d96c1575..4e1a2390f 100644
--- a/editors/vi.c
+++ b/editors/vi.c
@@ -1102,6 +1102,22 @@ static int get_one_char(void)
 # define get_one_char() readit()
 #endif
 
+// Get type of thing to operate on and adjust count
+static int get_motion_char(void)
+{
+        int c, cnt;
+
+        c = get_one_char();
+        if (c != '0' && isdigit(c)) {
+                // get any non-zero motion count
+                for (cnt = 0; isdigit(c); c = get_one_char())
+                        cnt = cnt * 10 + (c - '0');
+                cmdcnt = (cmdcnt ?: 1) * cnt;
+        }
+
+        return c;
+}
+
 // Get input line (uses "status line" area)
 static char *get_input_line(const char *prompt)
 {
@@ -3532,7 +3548,7 @@ static void do_cmd(int c)
         case '<':                       // <- Left  shift something
         case '>':                       // >- Right shift something
                 cnt = count_lines(text, dot);   // remember what line we are on
-                c1 = get_one_char();    // get the type of thing to delete
+                c1 = get_motion_char(); // get the type of thing to operate on
                 find_range(&p, &q, c1);
                 yank_delete(p, q, WHOLE, YANKONLY, NO_UNDO);    // save copy before change
                 p = begin_line(p);
@@ -3778,7 +3794,7 @@ static void do_cmd(int c)
 #endif
                 c1 = 'y';
                 if (c != 'Y') {
-                        c1 = get_one_char();    // get the type of thing to delete
+                        c1 = get_motion_char(); // get the type of thing to operate on
                         if (c1 == 27)   // ESC- user changed mind and wants out
                                 goto dc6;
                 }