Merge branch 'ls/editor-waiting-message'

Git shows a message to tell the user that it is waiting for the
user to finish editing when spawning an editor, in case the editor
opens to a hidden window or somewhere obscure and the user gets
lost.

* ls/editor-waiting-message:
  launch_editor(): indicate that Git waits for user input
  refactor "dumb" terminal determination

Documentation/config.txt

@@ -354,6 +354,9 @@ advice.*::
 	ignoredHook::
 		Advice shown if an hook is ignored because the hook is not
 		set as executable.
+	waitingForEditor::
+		Print a message to the terminal whenever Git is waiting for
+		editor input from the user.
 --
 
 core.fileMode::

advice.c

@@ -18,6 +18,7 @@ int advice_object_name_warning = 1;
 int advice_rm_hints = 1;
 int advice_add_embedded_repo = 1;
 int advice_ignored_hook = 1;
+int advice_waiting_for_editor = 1;
 
 static struct {
 	const char *name;
@@ -40,6 +41,7 @@ static struct {
 	{ "rmhints", &advice_rm_hints },
 	{ "addembeddedrepo", &advice_add_embedded_repo },
 	{ "ignoredhook", &advice_ignored_hook },
+	{ "waitingforeditor", &advice_waiting_for_editor },
 
 	/* make this an alias for backward compatibility */
 	{ "pushnonfastforward", &advice_push_update_rejected }

advice.h

@@ -20,6 +20,7 @@ extern int advice_object_name_warning;
 extern int advice_rm_hints;
 extern int advice_add_embedded_repo;
 extern int advice_ignored_hook;
+extern int advice_waiting_for_editor;
 
 int git_default_advice_config(const char *var, const char *value);
 __attribute__((format (printf, 1, 2)))

cache.h

@@ -1491,6 +1491,7 @@ extern const char *ident_default_name(void);
 extern const char *ident_default_email(void);
 extern const char *git_editor(void);
 extern const char *git_pager(int stdout_is_tty);
+extern int is_terminal_dumb(void);
 extern int git_ident_config(const char *, const char *, void *);
 extern void reset_ident_date(void);
 

color.c

@@ -329,8 +329,7 @@ static int check_auto_color(void)
 	if (color_stdout_is_tty < 0)
 		color_stdout_is_tty = isatty(1);
 	if (color_stdout_is_tty || (pager_in_use() && pager_use_color)) {
-		char *term = getenv("TERM");
-		if (term && strcmp(term, "dumb"))
+		if (!is_terminal_dumb())
 			return 1;
 	}
 	return 0;

editor.c

@@ -7,11 +7,16 @@
 #define DEFAULT_EDITOR "vi"
 #endif
 
+int is_terminal_dumb(void)
+{
+	const char *terminal = getenv("TERM");
+	return !terminal || !strcmp(terminal, "dumb");
+}
+
 const char *git_editor(void)
 {
 	const char *editor = getenv("GIT_EDITOR");
-	const char *terminal = getenv("TERM");
-	int terminal_is_dumb = !terminal || !strcmp(terminal, "dumb");
+	int terminal_is_dumb = is_terminal_dumb();
 
 	if (!editor && editor_program)
 		editor = editor_program;
@@ -40,6 +45,23 @@ int launch_editor(const char *path, struct strbuf *buffer, const char *const *en
 		const char *args[] = { editor, real_path(path), NULL };
 		struct child_process p = CHILD_PROCESS_INIT;
 		int ret, sig;
+		int print_waiting_for_editor = advice_waiting_for_editor && isatty(2);
+
+		if (print_waiting_for_editor) {
+			/*
+			 * A dumb terminal cannot erase the line later on. Add a
+			 * newline to separate the hint from subsequent output.
+			 *
+			 * Make sure that our message is separated with a whitespace
+			 * from further cruft that may be written by the editor.
+			 */
+			const char term = is_terminal_dumb() ? '\n' : ' ';
+
+			fprintf(stderr,
+				_("hint: Waiting for your editor to close the file...%c"),
+				term);
+			fflush(stderr);
+		}
 
 		p.argv = args;
 		p.env = env;
@@ -58,6 +80,13 @@ int launch_editor(const char *path, struct strbuf *buffer, const char *const *en
 		if (ret)
 			return error("There was a problem with the editor '%s'.",
 					editor);
+
+		if (print_waiting_for_editor && !is_terminal_dumb())
+			/*
+			 * Go back to the beginning and erase the entire line to
+			 * avoid wasting the vertical space.
+			 */
+			fputs("\r\033[K", stderr);
 	}
 
 	if (!buffer)

sideband.c

@@ -20,13 +20,12 @@
 
 int recv_sideband(const char *me, int in_stream, int out)
 {
-	const char *term, *suffix;
+	const char *suffix;
 	char buf[LARGE_PACKET_MAX + 1];
 	struct strbuf outbuf = STRBUF_INIT;
 	int retval = 0;
 
-	term = getenv("TERM");
-	if (isatty(2) && term && strcmp(term, "dumb"))
+	if (isatty(2) && !is_terminal_dumb())
 		suffix = ANSI_SUFFIX;
 	else
 		suffix = DUMB_SUFFIX;