#23 Parsing failures management

[Whitehouse112]

• Added IParseFailureObserver interface that defines parsing errors handling methods. Methods deal with both syntax errors and duplicated/not found key/name errors for nodes, messages, signals and so on.

• Provided two implemetations for the interface:
  1 - SilentFailureObserver: does nothing, like today. It's the default observer
  2 - SimpleFailureObserver: save each error in a list of string

• Added several tests for each parsing failure error

• Update Demo application to print errors, if any, using the SimpleFailureObserver class.

[EFeru]

Hi @Whitehouse112 , thanks for the effor in this PR. I am not sure if it is nomal, however if I run the Demo, I get the follwing warnings/failures:

[Whitehouse112]

Hi @EFeru,

• [VAL_] Value table syntax error: the syntax specification implemented in this library doesn't support a signed integer as a valid value description for the VAL_ keyword. Syntax is VAL_ var_name unsigned_integer char_string. The reported lines contain a negative number, from which the syntax error
• Unknown syntax error: this is something I need to change, it regards the NS_ definition at the beginning of the file. My though was to support only symbols actually implemented by the library itself but there is no reason to display this failures after all. I will fix asap.

Regards

[EFeru]

"Unknown syntax" is fixed. The following remained:

If I look in the dbc file indeed I see negative values for VAL_, is this something not supported by this library or the dbc file is not according to dbc Vector specs?

[Whitehouse112]

• It's something not supported by this library? Yes, It's not supported
• It's not compliant to the dbc Vector spec? I don't know: the only documentation available on the internet is the one provided also in this library and a signed integer is not a valid value for VAL_ tag.

So this library supports only unsigned integer since the only documentation available states that. This document is from 2010, I don't know if it has been updated, I looked for a recent version without success.

[Adhara3]

Hi,

It's very important that we find a reference and we stick with it. The document linked by @Whitehouse112 is by far the most complete and detailed resource we could find on the web.
Usually we also look for other software behaviour, we have the feeling that the specs are a bit sloppy so software got quite tolerant on syntax over time.

How is CANdb++ behaving with those lines?

My 2 cents
A

[EFeru]

CANdb++ just adds the value description without complains.

Edit: Just for completness, for the tesla dbc file, CANdb++ gives these results when running the consistency checks: