error out when no branches left

src/branches.cpp

@@ -80,11 +80,8 @@ namespace l
     uint64_t offset;
 
     offset = s_.find_first_not_of("+<>-=");
-    if(offset > 1)
-      offset = 2;
+    *values_ = ((offset != std::string::npos) ? s_.substr(offset) : "");
     *instr_ = s_.substr(0,offset);
-    if(offset != std::string::npos)
-      *values_ = s_.substr(offset);
   }
 
   static

tests/tests.cpp

@@ -164,6 +164,16 @@ test_config_update_branches()
   TEST_CHECK(b.to_string() == "/dir=RW");
   TEST_CHECK(b.from_string("/dir") == 0);
   TEST_CHECK(b.to_string() == "/dir=RW");
+
+  // error out when no branches left
+  TEST_CHECK(b.from_string("=/dir") == 0);
+  TEST_CHECK(b.from_string("-/dir") < 0);
+  TEST_CHECK(b.from_string("-<") < 0);
+  TEST_CHECK(b.from_string("->") < 0);
+
+  // error out when setting empty branches
+  TEST_CHECK(b.from_string("=") < 0);
+  TEST_CHECK(b.from_string("") < 0);
 }
 
 void