Diagnostic

A Diagnostic is the single, transport-agnostic representation of any error that stackie encounters while loading, parsing, or validating a block or stack definition. It is produced once — at the failure site — and then rendered by a DiagnosticRenderer appropriate to the surface in use:

• CLI: ariadne-based annotated YAML snippets with red underlines (see render_cli).
• API / MCP: JSON render_json::DiagnosticDto (see render_json).

Key Types

• Diagnostic — the core payload (code, message, YAML buffer, span, hint).
• DiagnosticCode — exhaustive enum identifying the error category.
• Severity — Error or Warning.
• Span — 1-indexed line/column range within the YAML source.
• DiagnosticRenderer — trait implemented by each transport.

Example

use stackie::diagnostic::{Diagnostic, DiagnosticCode, Severity, Span};
use std::sync::Arc;

let diag = Diagnostic {
    code: DiagnosticCode::E001Parse,
    severity: Severity::Error,
    message: "unexpected character at line 3".into(),
    source_file: None,
    yaml: Arc::from("name: postgres\ncommand:\n  run: [\n"),
    span: Some(Span { start_line: 3, start_col: 8, end_line: 3, end_col: 9 }),
    hint: Some("Check the YAML syntax around the opening bracket.".into()),
};