From 1333cf1168e645c82c620baa977ad9d777331f0b Mon Sep 17 00:00:00 2001
From: Marko Durkovic <marko@ternaris.com>
Date: Sun, 3 Oct 2021 06:28:02 +0200
Subject: [PATCH] Add string constant support to msg parser

---
 src/rosbags/typesys/msg.py | 10 ++++++++--
 tests/test_parse.py        |  3 ++-
 2 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/src/rosbags/typesys/msg.py b/src/rosbags/typesys/msg.py
index 51936893..8b326905 100644
--- a/src/rosbags/typesys/msg.py
+++ b/src/rosbags/typesys/msg.py
@@ -44,7 +44,8 @@ comment
   = r'#[^\n]*'
 
 const_dcl
-  = type_spec identifier '=' integer_literal
+  = 'string' identifier '=' r'[^\n]+'
+  / type_spec identifier '=' integer_literal
 
 field_dcl
   = type_spec identifier
@@ -172,7 +173,12 @@ class VisitorMSG(Visitor):
 
     def visit_const_dcl(self, children: Any) -> Any:
         """Process const declaration, suppress output."""
-        return Nodetype.CONST, (children[0][1], children[1][1], children[3])
+        typ = children[0][1]
+        if typ == 'string':
+            value = children[3].strip()
+        else:
+            value = children[3]
+        return Nodetype.CONST, (typ, children[1][1], value)
 
     def visit_specification(self, children: Any) -> Typesdict:
         """Process start symbol."""
diff --git a/tests/test_parse.py b/tests/test_parse.py
index e0fb995c..7f51ba85 100644
--- a/tests/test_parse.py
+++ b/tests/test_parse.py
@@ -18,6 +18,7 @@ MSG = """
 # comment
 
 int32 global=42
+string str= foo bar\t
 
 std_msgs/Header header
 std_msgs/msg/Bool bool
@@ -115,7 +116,7 @@ def test_parse_msg():
     ret = get_types_from_msg(MSG, 'test_msgs/msg/Foo')
     assert 'test_msgs/msg/Foo' in ret
     consts, fields = ret['test_msgs/msg/Foo']
-    assert consts == [('global', 'int32', 42)]
+    assert consts == [('global', 'int32', 42), ('str', 'string', 'foo bar')]
     assert fields[0][0] == 'header'
     assert fields[0][1][1] == 'std_msgs/msg/Header'
     assert fields[1][0] == 'bool'