From 1964240454d93493ee68a75b171fdf7934332200 Mon Sep 17 00:00:00 2001
From: Nick Bowler <nbowler@draconx.ca>
Date: Tue, 9 Mar 2021 20:25:21 -0500
Subject: [PATCH] Fix empty and help commands causing program exit.

This bug was introduced when the input handling was reworked: the
"help" and blank commands are now causing the program to exit.

Add some test coverage to ensure we don't regress again in the future.
---
 NEWS              |  1 +
 src/execute.gperf |  4 ++--
 tests/general.at  | 43 +++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 46 insertions(+), 2 deletions(-)

diff --git a/NEWS b/NEWS
index 2ba5206..94edf77 100644
--- a/NEWS
+++ b/NEWS
@@ -1,4 +1,5 @@
 Release 1a:
+	* Various bug fixes.
 
 Release 1:
 	* Initial release.
diff --git a/src/execute.gperf b/src/execute.gperf
index e8a0665..c667408 100644
--- a/src/execute.gperf
+++ b/src/execute.gperf
@@ -79,7 +79,7 @@ static int run_cmd_help(void)
 		print_block(gettext(strtab+c->cmd), 15, w);
 	}
 
-	return 1;
+	return 0;
 }
 
 int run_command(const char *line, int interactive)
@@ -90,7 +90,7 @@ int run_command(const char *line, int interactive)
 
 	/* empty command */
 	if (cmd[0] == '\0')
-		return 1;
+		return 0;
 
 	c = in_word_set(cmd, arg-cmd);
 	if (!c) {
diff --git a/tests/general.at b/tests/general.at
index 337afdd..38493ce 100644
--- a/tests/general.at
+++ b/tests/general.at
@@ -29,3 +29,46 @@ AT_CHECK([$SHELL "$builddir/exported.sh" "$archive" || exit 99], [0], [stdout])
 AT_CHECK([sed '/^cdecl_/d' stdout])
 
 AT_CLEANUP
+
+dnl Verify that empty commands do nothing.
+AT_SETUP([cdecl99 empty command])
+
+AT_DATA([input], [[explain int x[42];
+
+declare x as array 42 of int
+
+explain int
+
+]])
+
+AT_CHECK([cdecl99 -f input], [0], [[declare x as array 42 of int
+int x[42]
+type int
+]])
+
+AT_CLEANUP
+
+dnl Verify that commands are not executed after "quit"
+AT_SETUP([cdecl99 quit command])
+
+AT_DATA([input], [[explain int;
+quit
+explain this is a syntax error
+]])
+
+AT_CHECK([cdecl99 -f input], [0], [type int
+])
+
+AT_CLEANUP
+
+AT_SETUP([cdecl99 help command])
+
+AT_DATA([input], [[help
+explain int
+]])
+
+AT_CHECK([cdecl99 -f input], [0], [stdout])
+AT_CHECK([sed -n '$p' stdout], [0], [type int
+])
+
+AT_CLEANUP
-- 
2.43.2