lib: add `![...]` syntax for easy "no" forms

This allows defining a CLI command like this:
  `[no] some setting ![VALUE]`
with VALUE being optional for the "no" form, but required for the
positive form.  It's just a `[...]` where the empty branch can only be
taken for commands starting with `no`.

Signed-off-by: David Lamparter <equinox@opensourcerouting.org>

3 files changed, 116 insertions, 1 deletions

diff --git a/tests/lib/cli/test_cli.c b/tests/lib/cli/test_cli.c
index 8dba1e29f0..f8d74018dd 100644
--- a/tests/lib/cli/test_cli.c
+++ b/tests/lib/cli/test_cli.c
@@ -40,6 +40,8 @@ DUMMY_DEFUN(cmd12, "alt a A.B.C.D");
 DUMMY_DEFUN(cmd13, "alt a X:X::X:X");
 DUMMY_DEFUN(cmd14,
 	    "pat g {  foo A.B.C.D$foo|foo|bar   X:X::X:X$bar| baz } [final]");
+DUMMY_DEFUN(cmd15, "no pat g ![ WORD ]");
+DUMMY_DEFUN(cmd16, "[no] pat h {foo ![A.B.C.D$foo]|bar X:X::X:X$bar} final");
 
 #include "tests/lib/cli/test_cli_clippy.c"
 
@@ -81,5 +83,7 @@ void test_init(int argc, char **argv)
 		install_element(ENABLE_NODE, &cmd13_cmd);
 	}
 	install_element(ENABLE_NODE, &cmd14_cmd);
+	install_element(ENABLE_NODE, &cmd15_cmd);
+	install_element(ENABLE_NODE, &cmd16_cmd);
 	install_element(ENABLE_NODE, &magic_test_cmd);
 }
diff --git a/tests/lib/cli/test_cli.in b/tests/lib/cli/test_cli.in
index 5c146ef984..bd685a6231 100644
--- a/tests/lib/cli/test_cli.in
+++ b/tests/lib/cli/test_cli.in
@@ -74,6 +74,23 @@ pat f
 pat f foo
 pat f key
 
+no pat g
+no pat g test
+no pat g test more
+
+pat h foo ?1.2.3.4 final
+no pat h foo ?1.2.3.4 final
+pat h foo final
+no pat h foo final
+pat h bar final
+no pat h bar final
+pat h bar 1::2 final
+no pat h bar 1::2 final
+pat h bar 1::2 foo final
+no pat h bar 1::2 foo final
+pat h bar 1::2 foo 1.2.3.4 final
+no pat h bar 1::2 foo 1.2.3.4 final
+
 alt a 	a?b
 alt a 1	.2?.3.4
 alt a 1	:2?	::?3
diff --git a/tests/lib/cli/test_cli.refout.in b/tests/lib/cli/test_cli.refout.in
index 8f9959cc47..8a9eaf38fb 100644
--- a/tests/lib/cli/test_cli.refout.in
+++ b/tests/lib/cli/test_cli.refout.in
@@ -147,7 +147,7 @@ test# papat
 % Command incomplete.

 test# pat 

 a          b          c          d          e          f          

-g          

+g          h          

 test# pat 

 % Command incomplete.

 test# 

@@ -263,6 +263,100 @@ cmd10 with 3 args.
 [01] f@(null): f

 [02] key@(null): key

 test# 

+test# no pat g

+cmd15 with 3 args.

+[00] no@(null): no

+[01] pat@(null): pat

+[02] g@(null): g

+test# no pat g test

+cmd15 with 4 args.

+[00] no@(null): no

+[01] pat@(null): pat

+[02] g@(null): g

+[03] WORD@g: test

+test# no pat g test more

+% [NONE] Unknown command: no pat g test more

+test# 

+test# pat h foo 

+  A.B.C.D  04

+test# pat h foo 1.2.3.4 final

+cmd16 with 5 args.

+[00] pat@(null): pat

+[01] h@(null): h

+[02] foo@(null): foo

+[03] A.B.C.D@foo: 1.2.3.4

+[04] final@(null): final

+test# no pat h foo 

+  A.B.C.D  04

+  bar      05

+  final    07

+test# no pat h foo 1.2.3.4 final

+cmd16 with 6 args.

+[00] no@no: no

+[01] pat@(null): pat

+[02] h@(null): h

+[03] foo@(null): foo

+[04] A.B.C.D@foo: 1.2.3.4

+[05] final@(null): final

+test# pat h foo final

+% [NONE] Unknown command: pat h foo final

+test# no pat h foo final

+cmd16 with 5 args.

+[00] no@no: no

+[01] pat@(null): pat

+[02] h@(null): h

+[03] foo@(null): foo

+[04] final@(null): final

+test# pat h bar final

+% [NONE] Unknown command: pat h bar final

+test# no pat h bar final

+% [NONE] Unknown command: no pat h bar final

+test# pat h bar 1::2 final

+cmd16 with 5 args.

+[00] pat@(null): pat

+[01] h@(null): h

+[02] bar@(null): bar

+[03] X:X::X:X@bar: 1::2

+[04] final@(null): final

+test# no pat h bar 1::2 final

+cmd16 with 6 args.

+[00] no@no: no

+[01] pat@(null): pat

+[02] h@(null): h

+[03] bar@(null): bar

+[04] X:X::X:X@bar: 1::2

+[05] final@(null): final

+test# pat h bar 1::2 foo final

+% [NONE] Unknown command: pat h bar 1::2 foo final

+test# no pat h bar 1::2 foo final

+cmd16 with 7 args.

+[00] no@no: no

+[01] pat@(null): pat

+[02] h@(null): h

+[03] bar@(null): bar

+[04] X:X::X:X@bar: 1::2

+[05] foo@(null): foo

+[06] final@(null): final

+test# pat h bar 1::2 foo 1.2.3.4 final

+cmd16 with 7 args.

+[00] pat@(null): pat

+[01] h@(null): h

+[02] bar@(null): bar

+[03] X:X::X:X@bar: 1::2

+[04] foo@(null): foo

+[05] A.B.C.D@foo: 1.2.3.4

+[06] final@(null): final

+test# no pat h bar 1::2 foo 1.2.3.4 final

+cmd16 with 8 args.

+[00] no@no: no

+[01] pat@(null): pat

+[02] h@(null): h

+[03] bar@(null): bar

+[04] X:X::X:X@bar: 1::2

+[05] foo@(null): foo

+[06] A.B.C.D@foo: 1.2.3.4

+[07] final@(null): final

+test# 

 test# alt a 

 test# alt a a

   WORD      02