fix: cjs-shaped type declaration

Fixes an issue where the compiler complained the default export
was not constructable

Author: wkillerud

metric.d.ts

@@ -1,80 +1,84 @@
-/**
- * A hint of what type of metric this is. Each numeric value represents a different type of metric:
- *
- *  - `0`: `unknown`
- *  - `1`: `gauge`
- *  - `2`: `counter`
- *  - `3`: `state_set`
- *  - `4`: `info`
- *  - `5`: `cumulative histogram`
- *  - `6`: `gauge histogram`
- *  - `7`: `summary`
- */
-export type MetricType = 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7;
-
-export type MetricLabel = {
-  /**
-   * The name must match the regular expression `[a-zA-Z0-9_]`.
-   */
-  name: string;
-  value: string | number | boolean | null;
-}
-
-export type MetricOptions = {
-  /**
-   * The name must match the regular expression `[a-zA-Z_:][a-zA-Z0-9_:]*`.
-   *
-   * By convention, colons are reserved for monitoring system use, and names
-   * beginning with underscores are reserved for monitoring-system internal use.
-   */
-  name: string;
-  description: string;
-  /**
-   * @default Date.now() / 1000
-   */
-  timestamp?: number | null;
-  /**
-   * @deprecated Use `timestamp` instead.
-   */
-  time?: number | null;
-  source?: string | null;
-  labels?: Array<MetricLabel>;
-  value?: number | null;
-  /**
-   * @default 0 (`unknown`)
-   */
-  type?: MetricType;
-  /**
-   * Arbitrary metadata to attach to this metric. This field is not validated.
-   * @default {}
-   */
-  meta?: unknown;
-}
-
-export default class Metric {
-    constructor(args: MetricOptions);
+declare class Metric {
+    constructor(args: Metric.MetricOptions);
 
     name: Readonly<string>;
     description: Readonly<string>;
     value: Readonly<number | null>;
-    type: Readonly<MetricType>;
+    type: Readonly<Metric.MetricType>;
     source: string | null;
     timestamp: Readonly<number | null>;
     /**
      * @deprecated Use `timestamp` instead.
      */
     time: Readonly<number | null>;
-    labels: Readonly<Array<MetricLabel>>;
+    labels: Readonly<Array<Metric.MetricLabel>>;
     meta: Readonly<unknown>;
 
     toJSON(): {
-      name: string;
-      description: string;
-      timestamp: number | null;
-      type: MetricType;
-      value: number | null;
-      labels: Array<MetricLabel>;
-      time: number | null;
-      meta: unknown;
+        name: string;
+        description: string;
+        timestamp: number | null;
+        type: Metric.MetricType;
+        value: number | null;
+        labels: Array<Metric.MetricLabel>;
+        time: number | null;
+        meta: unknown;
+    };
+}
+
+declare namespace Metric {
+    /**
+     * A hint of what type of metric this is. Each numeric value represents a different type of metric:
+     *
+     *  - `0`: `unknown`
+     *  - `1`: `gauge`
+     *  - `2`: `counter`
+     *  - `3`: `state_set`
+     *  - `4`: `info`
+     *  - `5`: `cumulative histogram`
+     *  - `6`: `gauge histogram`
+     *  - `7`: `summary`
+     */
+    export type MetricType = 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7;
+
+    export type MetricLabel = {
+        /**
+         * The name must match the regular expression `[a-zA-Z0-9_]`.
+         */
+        name: string;
+        value: string | number | boolean | null;
+    };
+
+    export type MetricOptions = {
+        /**
+         * The name must match the regular expression `[a-zA-Z_:][a-zA-Z0-9_:]*`.
+         *
+         * By convention, colons are reserved for monitoring system use, and names
+         * beginning with underscores are reserved for monitoring-system internal use.
+         */
+        name: string;
+        description: string;
+        /**
+         * @default Date.now() / 1000
+         */
+        timestamp?: number | null;
+        /**
+         * @deprecated Use `timestamp` instead.
+         */
+        time?: number | null;
+        source?: string | null;
+        labels?: Array<MetricLabel>;
+        value?: number | null;
+        /**
+         * @default 0 (`unknown`)
+         */
+        type?: MetricType;
+        /**
+         * Arbitrary metadata to attach to this  This field is not validated.
+         * @default {}
+         */
+        meta?: unknown;
     };
 }
+
+export = Metric;