Add custom error with variants to `parser` module

[CalemRoelofs]

Closes #38

This PR adds the parser::errors submodule using thiserror to handle different variants. In the parser::parser module, almost all calls to unwrap() have been replaced and functions now return Result<T, JsonPathParserError> instead. Changing the signature of the public method parse_json_path from Result<JsonPath, pest::error::Error<Rule>> to Result<JsonPath, JsonPathParsingError> is considered a breaking change so I'll leave it you you @besok on how you want to handle bumping versions etc. There's a bit of extra boilerplate added to the existing functions where Option<T> is now Result<Option<T>, JsonPathParserError> but I've tried to make it as concise as possible.

[besok]

Closes #38

This PR adds the parser::errors submodule using thiserror to handle different variants. In the parser::parser module, almost all calls to unwrap() have been replaced and functions now return Result<T, JsonPathParserError> instead. Changing the signature of the public method parse_json_path from Result<JsonPath, pest::error::Error<Rule>> to Result<JsonPath, JsonPathParsingError> is considered a breaking change so I'll leave it you you @besok on how you want to handle bumping versions etc. There's a bit of extra boilerplate added to the existing functions where Option<T> is now Result<Option<T>, JsonPathParserError> but I've tried to make it as concise as possible.

The PR looks very good. Nice job! I added just a couple of comments, just to correct a little.

Changing the signature of the public method parse_json_path from Result<JsonPath, pest::error::Error<Rule>> to Result<JsonPath, JsonPathParsingError> is considered a breaking change so I'll leave it you you @besok on how you want to handle bumping versions etc.

Yeah, it seems fine, but I would ensure the new error enum has a to_string implementation as we convert it to string here and either change TryInto or add to_string

[CalemRoelofs]

@besok thank you for the feedback! I'll implement these changes in the coming week.

[CalemRoelofs]

@besok I've refactored out most of the unwrap_or statements, but I'm a bit unsure of what the error messages returned from ok_or actually should be. Open to any and all suggestions 😄

[besok]

@CalemRoelofs Yeah, looks good to me. The messages just say where is the error and we can have a look there. It is enough I think.

[besok]

Ah, the build error with Clippy, you need to fix a small warning Just run locally:

cargo clippy --workspace --tests --all-features -- -D warnings

[CalemRoelofs]

Ah, the build error with Clippy, you need to fix a small warning Just run locally:

cargo clippy --workspace --tests --all-features -- -D warnings

Fixed now :)

[besok]

thank you very much for the PR!