New command require-final-newline <nil | T | ask>

Disabled by default.  Fixes #25

Signed-off-by: Joachim Wiberg <[email protected]>

doc/mg.1

@@ -885,6 +885,14 @@ is negative, it is that line from the bottom.
 .It Ic redraw-display
 Refresh the display.
 Recomputes all window sizes in case something has changed.
+.It Ic require-final-newline <nil | T | ask>
+Require files to have a final newline added when saving.  By default
+this is disabled (nil).  To always add a missing newline set to
+.Ic T ,
+to restore the original
+.Nm
+behavior, use
+.Ic ask .
 .It Ic revert-buffer
 Revert the current buffer to the latest file on disk.
 .It Ic save-buffer
@@ -966,7 +974,7 @@ Sets the mark in the current window to the current dot location.
 Sets the prefix string to be used by the
 .Ic prefix-region
 command.
-.It set-tab-width
+.It Ic set-tab-width
 Set the tab width for the current buffer, or the default for new buffers
 if called with a prefix argument or from the startup file.
 .It Ic shell-command

src/def.h

@@ -474,6 +474,7 @@ int		 filewrite(int, int);
 int		 filesave(int, int);
 int		 buffsave(struct buffer *);
 int		 makebkfile(int, int);
+int		 reqnewline(int, int);
 int		 writeout(FILE **, struct buffer *, char *);
 void		 upmodes(struct buffer *);
 size_t		 xbasename(char *, const char *, size_t);

src/file.c

@@ -17,6 +17,8 @@
 
 #include "def.h"
 
+static int reqnl = FALSE;  /* Don't enforce final newline by default. */
+
 size_t xdirname(char *, const char *, size_t);
 
 /*
@@ -663,6 +665,26 @@ makebkfile(int f, int n)
 	return (TRUE);
 }
 
+int
+reqnewline(int f, int n)
+{
+	char buf[5], *arg;
+
+	arg = eread("Require newline at EOF (nil, t, ask): ", buf, sizeof(buf), EFNEW);
+	if (arg == NULL)
+		return (ABORT);
+
+	if (!strcasecmp(arg, "nil"))
+		reqnl = FALSE;
+	else if (!strcasecmp(arg, "t"))
+		reqnl = TRUE;
+	else if (!strcasecmp(arg, "ask"))
+		reqnl = 2;
+	else
+		return (FALSE);
+	return (TRUE);
+}
+
 /*
  * NB: bp is passed to both ffwopen and ffclose because some
  * attribute information may need to be updated at open time
@@ -703,7 +725,10 @@ writeout(FILE ** ffp, struct buffer *bp, char *fn)
 	lpend = bp->b_headp;
 	eobnl = 0;
 	if (llength(lback(lpend)) != 0) {
-		eobnl = eyorn("No newline at end of file, add one");
+		if (reqnl == 2)
+			eobnl = eyorn("No newline at end of file, add one");
+		else
+			eobnl = reqnl;
 		if (eobnl != TRUE && eobnl != FALSE)
 			return (eobnl); /* abort */
 	}

src/funmap.c

@@ -201,6 +201,7 @@ static struct funmap functnames[] = {
 	{re_repl, "replace-regexp", 2, NULL},
 	{replstr, "replace-string", 2, NULL},
 #endif /* REGEX */
+	{reqnewline, "require-final-newline", 1, NULL},
 	{revertbuffer, "revert-buffer", 0, NULL},
 	{filesave, "save-buffer", 1, NULL},
 	{quit, "save-buffers-kill-emacs", 0, NULL},