feat: core grammar, discovery and renderer; Postgres dialect; conformance suite

2026-11-02 01:11:38 +01:00
commit 4b276f21e3
54 changed files with 4103 additions and 0 deletions
@@ -0,0 +1,28 @@
+import { badRequest } from '../errors.js';
+import type { Column, Relation, Resource } from '../resources.js';
+import type { Segment } from './names.js';
+
+export interface Resolved { relations: Relation[]; resource: Resource; last: Segment }
+
+/**
+ * Walks the leading segments as relations and returns the resource the last
+ * segment is read on. A quoted segment is a column, so it cannot be a hop.
+ */
+export function walk(resource: Resource, segs: Segment[], depth: number): Resolved {
+    const relations: Relation[] = [];
+    let current = resource;
+    for (const seg of segs.slice(0, -1)) {
+        const rel = seg.quoted ? undefined : current.relations.get(seg.name);
+        if (!rel) throw badRequest('unknown_relation', seg.name);
+        relations.push(rel);
+        current = rel.target;
+    }
+    if (relations.length > depth) throw badRequest('too_deep', segs.map((s) => s.name).join('.'));
+    return { relations, resource: current, last: segs[segs.length - 1] };
+}
+
+export function column(resource: Resource, name: string): Column {
+    const c = resource.columns.get(name);
+    if (!c) throw badRequest('unknown_column', name);
+    return c;
+}