Parser: Analyze and transform Action View helpers

[marcoroth]

This pull request adds the foundation for parsing and analyzing Action View tag helpers. To start with, only a few helpers are supported, tag.*, content_tag, and link_to. But more can be added by extending the handler registry.

A new action_view_helpers parser option is available to enable this analysis (defaults to false). When enabled, the parser detects supported helper calls and transforms them into synthetic HTMLElementNode AST representations. HTML attributes are extracted from Ruby keyword arguments, including data/aria nested hashes, attribute splats, interpolated strings, and method/remote to data-* conversions.

This also introduces several new AST node types: ERBOpenTagNode, HTMLVirtualCloseTagNode, RubyHTMLAttributesSplatNode, and RubyLiteralNode.

For example, the following template:

<%= tag.div class: "wrapper", data: { controller: "hello" } do %>
  Hello
<% end %>

Gets parsed and transformed to:

@ DocumentNode (location: (1:0)-(3:9))
└── children: (1 item)
    └── @ HTMLElementNode (location: (1:0)-(3:9))
        ├── open_tag: 
        │   └── @ ERBOpenTagNode (location: (1:0)-(1:65))
        │       ├── tag_opening: "<%=" (location: (1:0)-(1:3))
        │       ├── content: " tag.div class: "wrapper", data: { controller: "hello" } do " (location: (1:3)-(1:63))
        │       ├── tag_closing: "%>" (location: (1:63)-(1:65))
        │       ├── tag_name: "div" (location: (1:8)-(1:11))
        │       └── children: (2 items)
        │           ├── @ HTMLAttributeNode (location: (1:12)-(1:19))
        │           │   ├── name: 
        │           │   │   └── @ HTMLAttributeNameNode (location: (1:12)-(1:19))
        │           │   │       └── children: (1 item)
        │           │   │           └── @ LiteralNode (location: (1:12)-(1:19))
        │           │   │               └── content: "class"
        │           │   │       
        │           │   ├── equals: "=" (location: (1:12)-(1:19))
        │           │   └── value: 
        │           │       └── @ HTMLAttributeValueNode (location: (1:12)-(1:19))
        │           │           ├── open_quote: """ (location: (1:12)-(1:19))
        │           │           ├── children: (1 item)
        │           │           │   └── @ LiteralNode (location: (1:12)-(1:19))
        │           │           │       └── content: "wrapper"
        │           │           │       
        │           │           ├── close_quote: """ (location: (1:19)-(1:19))
        │           │           └── quoted: true
        │           │   
        │           └── @ HTMLAttributeNode (location: (1:38)-(1:50))
        │               ├── name: 
        │               │   └── @ HTMLAttributeNameNode (location: (1:38)-(1:50))
        │               │       ├── errors: []
        │               │       └── children: (1 item)
        │               │           └── @ LiteralNode (location: (1:38)-(1:50))
        │               │               └── content: "data-controller"
        │               │               
        │               ├── equals: "=" (location: (1:38)-(1:50))
        │               └── value: 
        │                   └── @ HTMLAttributeValueNode (location: (1:38)-(1:50))
        │                       ├── open_quote: """ (location: (1:38)-(1:50))
        │                       ├── children: (1 item)
        │                       │   └── @ LiteralNode (location: (1:38)-(1:50))
        │                       │       └── content: "hello"
        │                       │   
        │                       ├── close_quote: """ (location: (1:50)-(1:50))
        │                       └── quoted: true
        │               
        ├── tag_name: "div" (location: (1:8)-(1:11))
        ├── body: (1 item)
        │   └── @ HTMLTextNode (location: (1:65)-(3:0))
        │       └── content: "\n  Hello\n"
        │       
        ├── close_tag: 
        │   └── @ ERBEndNode (location: (3:0)-(3:9))
        │       ├── tag_opening: "<%" (location: (3:0)-(3:2))
        │       ├── content: " end " (location: (3:2)-(3:7))
        │       └── tag_closing: "%>" (location: (3:7)-(3:9))
        │       
        ├── is_void: false
        └── element_source: "ActionView::Helpers::TagHelper#tag"

The location reporting for the HTML attribute nodes can still be improved and is going be necessary if we want to improve stimulus-lint for example, so we can accurately show which part of Ruby is relevant.

Resolves #1122

[pkg-pr-new]

npx https://pkg.pr.new/@herb-tools/formatter@1347

npx https://pkg.pr.new/@herb-tools/language-server@1347

npx https://pkg.pr.new/@herb-tools/linter@1347

commit: 4e94e0d

[github-actions]

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