feat: mockly-hono — file-based mock API server (Hono)

File path = route. JSON/JSON5, dynamic .ts handlers + faker, templating,
stateful CRUD (pagination/sort/persist), __variants, sequence, chaos,
rate-limit, auth, validation, per-route + global proxy/record, splat routes,
X-Scenario overlays, SSE. Visual docs (Scalar) at /__docs from a live
OpenAPI 3 spec. OpenAPI import script. Zero-build via tsx.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/template.ts

@@ -0,0 +1,58 @@
+import type { MockContext } from './respond.ts'
+
+/**
+ * Replace `{{ path }}` placeholders inside a JSON value.
+ *   {{params.id}}  {{query.q}}  {{headers.x-foo}}
+ *   {{faker.person.fullName}}  {{faker.number.int}}  (zero-arg faker methods)
+ * If a string is exactly one placeholder, the resolved (typed) value is used —
+ * so {{faker.number.int}} yields a number, not "123".
+ */
+const RE = /\{\{\s*([\w.$-]+)\s*\}\}/g
+
+function resolve(path: string, ctx: MockContext): unknown {
+  const parts = path.split('.')
+  let cur: any =
+    parts[0] === 'faker'
+      ? ctx.faker
+      : parts[0] === 'params'
+        ? ctx.params
+        : parts[0] === 'query'
+          ? ctx.query
+          : parts[0] === 'headers'
+            ? ctx.headers
+            : undefined
+  if (cur === undefined) return undefined
+  for (let i = 1; i < parts.length; i++) {
+    cur = cur?.[parts[i]]
+    if (cur === undefined) return undefined
+  }
+  return typeof cur === 'function' ? cur.call(parts[0] === 'faker' ? undefined : cur) : cur
+}
+
+export function hasTemplate(v: unknown): boolean {
+  if (typeof v === 'string') return RE.test(v)
+  if (Array.isArray(v)) return v.some(hasTemplate)
+  if (v && typeof v === 'object') return Object.values(v).some(hasTemplate)
+  return false
+}
+
+export function applyTemplate(value: unknown, ctx: MockContext): unknown {
+  if (typeof value === 'string') {
+    const whole = value.match(/^\{\{\s*([\w.$-]+)\s*\}\}$/)
+    if (whole) {
+      const r = resolve(whole[1], ctx)
+      return r === undefined ? value : r
+    }
+    return value.replace(RE, (m, p) => {
+      const r = resolve(p, ctx)
+      return r === undefined ? m : String(r)
+    })
+  }
+  if (Array.isArray(value)) return value.map((v) => applyTemplate(v, ctx))
+  if (value && typeof value === 'object') {
+    const out: Record<string, unknown> = {}
+    for (const [k, v] of Object.entries(value)) out[k] = applyTemplate(v, ctx)
+    return out
+  }
+  return value
+}