Amending YAML parser to add support for tags

[greg-at-moderne]

What's changed?

Adding support for tags in YAML, e.g.

AttributeDefinitions: !Dynamo Title

!Dynamo is a tag here.

What's your motivation?

Observed in real-life YAMLs that they sometimes use tags.
Currently they have been accidentally supported in some cases. E.g. for scalars we used to consider !Dynamo Title to be the value.

Anything in particular you'd like reviewers to focus on?

The LST model for YAML has been amended to include two new fields called tag in Scalar and Sequence. Which is not fully backward compatible. E.g. if someone has a recipe which does new Yaml.Scalar(...), the code will no longer compile for 1 extra argument missing.
Not sure how do we provide coverage for these scenarios.

[github-actions]

Some suggestions could not be made:

• rewrite-gradle/src/main/java/org/openrewrite/gradle/RemoveRedundantDependencyVersions.java
  • lines 240-241
• rewrite-maven/src/test/java/org/openrewrite/maven/internal/MavenPomDownloaderTest.java
  • lines 1278-1278

[knutwannheden]

It looks like we haven't added support for tags to Yaml.Mapping. In the globalTags() test case there is one example and the tags ends up in the prefix of the mapping's first entry (see debugger screenshot). Here is the corresponding YAML:

person: !!map
  name: John Doe
  age: 30

I think it would probably make sense to support YAML mapping tags at the same time.

Further, I think the !! syntax are implicit global tags. There are also explicit global tags like: !<tag:yaml.org,2002:str> "Hello" (which is semantically equivalent to !!str) and any tag not using the !<> (or !!) syntax is a "local" tag. I wonder if these details should be part of the LST model rather than being implicitly encoded as the tag's "name".

[github-actions]

Some suggestions could not be made:

• rewrite-gradle/src/main/java/org/openrewrite/gradle/RemoveRedundantDependencyVersions.java
  • lines 240-241
• rewrite-maven/src/test/java/org/openrewrite/maven/internal/MavenPomDownloaderTest.java
  • lines 1278-1278

[greg-at-moderne]

It looks like we haven't added support for tags to Yaml.Mapping

Added in 6344b6a

[greg-at-moderne]

tag's "name"

Renamed the field to text in 79f22f7

[github-actions]

Some suggestions could not be made:

• rewrite-gradle/src/main/java/org/openrewrite/gradle/RemoveRedundantDependencyVersions.java
  • lines 240-241
• rewrite-maven/src/test/java/org/openrewrite/maven/internal/MavenPomDownloaderTest.java
  • lines 1278-1278

[greg-at-moderne]

I wonder if these details should be part of the LST model rather than being implicitly encoded as the tag's "name".

Added in adf3fbb