# HG changeset patch
# User Jun Wu <quark@fb.com>
# Date 1457959955 0
# Node ID 3bf2892f685f3e240768e2f3b109f4a61a7839d3
# Parent  491eabd0df79ac5f9a0719cd1c26e480212457ba
chgserver: handle ParseError during validate

Currently the validate command in chgserver expects config can be loaded
without issues but the config can be broken and chg will print a stacktrace
instead of the parsing error, if a chg server is already running.

This patch adds a handler for ParseError in validate and a new instruction
"exit" to make the client exit without abortmsg. A test is also added to make
sure it will behave as expected.

diff -r 491eabd0df79 -r 3bf2892f685f contrib/chg/chg.c
--- a/contrib/chg/chg.c	Mon Mar 14 12:32:09 2016 +0000
+++ b/contrib/chg/chg.c	Mon Mar 14 12:52:35 2016 +0000
@@ -460,6 +460,11 @@
 					 "%s", *pinst + 9);
 			if (r < 0 || r >= (int)sizeof(opts->redirectsockname))
 				abortmsg("redirect path is too long (%d)", r);
+		} else if (strncmp(*pinst, "exit ", 5) == 0) {
+			int n = 0;
+			if (sscanf(*pinst + 5, "%d", &n) != 1)
+				abortmsg("cannot read the exit code");
+			exit(n);
 		} else {
 			abortmsg("unknown instruction: %s", *pinst);
 		}
diff -r 491eabd0df79 -r 3bf2892f685f hgext/chgserver.py
--- a/hgext/chgserver.py	Mon Mar 14 12:32:09 2016 +0000
+++ b/hgext/chgserver.py	Mon Mar 14 12:52:35 2016 +0000
@@ -429,9 +429,17 @@
               outdated server.
             - "redirect $path", the client should try to connect to another
               server instead.
+            - "exit $n", the client should exit directly with code n.
+              This may happen if we cannot parse the config.
         """
         args = self._readlist()
-        self.ui = _renewui(self.ui, args)
+        try:
+            self.ui = _renewui(self.ui, args)
+        except error.ParseError as inst:
+            dispatch._formatparse(self.ui.warn, inst)
+            self.ui.flush()
+            self.cresult.write('exit 255')
+            return
         newhash = hashstate.fromui(self.ui, self.hashstate.mtimepaths)
         insts = []
         if newhash.mtimehash != self.hashstate.mtimehash:
diff -r 491eabd0df79 -r 3bf2892f685f tests/test-chg.t
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/tests/test-chg.t	Mon Mar 14 12:52:35 2016 +0000
@@ -0,0 +1,12 @@
+init repo
+
+  $ hg init foo
+  $ cd foo
+
+ill-formed config
+
+  $ hg status
+  $ echo '=brokenconfig' >> $HGRCPATH
+  $ hg status
+  hg: parse error at * (glob)
+  [255]