fix: export errors

README.md

@@ -85,6 +85,7 @@ Its API lets you access both computed and raw values, where possible.
   * [`doc.eventLoopUtilizationSupported`](#doceventlooputilizationsupported)
   * [`doc.resourceUsageSupported`](#docresourceusagesupported)
   * [`doc.gcFlagsSupported`](#docgcflagssupported)
+  * [`doc.errors`](#docerrors)
 
 <!-- tocstop -->
 
@@ -393,31 +394,31 @@ It tracks the global activity of the garbage collector.
 
 * [`<GCEntry>`](#class-gcentry) | [`<GCAggregatedEntry>`](#class-gcaggregatedentry)
 
-The activity of the operation of type `major`. It's present only if `GCMEtric` has been created with the option `aggregate` equal to `true`.
+The activity of the operation of type `major`. It's present only if `GCMetric` has been created with the option `aggregate` equal to `true`.
 
 See [`performanceEntry.kind`](https://nodejs.org/dist/latest-v12.x/docs/api/perf_hooks.html#perf_hooks_performanceentry_kind).
 
 #### `gcMetric.minor`
 
 * [`<GCEntry>`](#class-gcentry) | [`<GCAggregatedEntry>`](#class-gcaggregatedentry)
 
-The activity of the operation of type `minor`. It's present only if `GCMEtric` has been created with the option `aggregate` equal to `true`.
+The activity of the operation of type `minor`. It's present only if `GCMetric` has been created with the option `aggregate` equal to `true`.
 
 See [`performanceEntry.kind`](https://nodejs.org/dist/latest-v12.x/docs/api/perf_hooks.html#perf_hooks_performanceentry_kind).
 
 #### `gcMetric.incremental`
 
 * [`<GCEntry>`](#class-gcentry) | [`<GCAggregatedEntry>`](#class-gcaggregatedentry)
 
-The activity of the operation of type `incremental`. It's present only if `GCMEtric` has been created with the option `aggregate` equal to `true`.
+The activity of the operation of type `incremental`. It's present only if `GCMetric` has been created with the option `aggregate` equal to `true`.
 
 See [`performanceEntry.kind`](https://nodejs.org/dist/latest-v12.x/docs/api/perf_hooks.html#perf_hooks_performanceentry_kind).
 
 #### `gcMetric.weakCb`
 
 * [`<GCEntry>`](#class-gcentry) | [`<GCAggregatedEntry>`](#class-gcaggregatedentry)
 
-The activity of the operation of type `weakCb`. It's present only if `GCMEtric` has been created with the option `aggregate` equal to `true`.
+The activity of the operation of type `weakCb`. It's present only if `GCMetric` has been created with the option `aggregate` equal to `true`.
 
 See [`performanceEntry.kind`](https://nodejs.org/dist/latest-v12.x/docs/api/perf_hooks.html#perf_hooks_performanceentry_kind).
 
@@ -427,7 +428,7 @@ It contains garbage collection data, represented with an [hdr histogram](https:/
 
 #### `new GCEntry()`
 
-The initialization doesn't require options. It is created internally by a [`GCMEtric`](#class-gcmetric).
+The initialization doesn't require options. It is created internally by a [`GCMetric`](#class-gcmetric).
 
 #### `gcEntry.totalDuration`
 
@@ -482,7 +483,7 @@ It extends [`GCEntry`](#class-gcentry) and contains garbage collection data plus
 
 #### `new GCAggregatedEntry()`
 
-The initialization doesn't require options. It is created internally by a [`GCMEtric`](#class-gcmetric).
+The initialization doesn't require options. It is created internally by a [`GCMetric`](#class-gcmetric).
 
 #### `gcAggregatedEntry.flags`
 
@@ -538,3 +539,12 @@ It tells if the Node.js version in use supports the [resourceUsage metric](https
 * `<boolean>`
 
 It tells if the Node.js version in use supports [GC flags](https://nodejs.org/dist/latest-v12.x/docs/api/perf_hooks.html#perf_hooks_performanceentry_flags).
+
+### `doc.errors`
+
+In the `errors` object are exported all the custom errors used by the module.
+
+| Error | Error Code | Description |
+|-------|------------|-------------|
+| `InvalidArgumentError` | `DOC_ERR_INVALID_ARG` | An invalid option or argument was used |
+| `NotSupportedError` | `DOC_ERR_NOT_SUPPORTED` | A metric is not supported on the Node.js version used |

index.d.ts

@@ -1,4 +1,5 @@
 import { Sampler, SamplerOptions } from './types/sampler'
+import errors = require('./types/errors')
 
 declare function createSampler(options?: SamplerOptions): Sampler
 export default createSampler
@@ -8,6 +9,7 @@ export const eventLoopUtilizationSupported: Boolean
 export const resourceUsageSupported: Boolean
 export const gcFlagsSupported: Boolean
 export { Sampler, SamplerOptions }
+export { errors }
 export * from './types/cpuMetric'
 export * from './types/eventLoopDelayMetric'
 export * from './types/resourceUsageMetric'

index.js

@@ -2,6 +2,7 @@
 
 const Sampler = require('./lib/sampler')
 const util = require('./lib/util')
+const errors = require('./lib/errors')
 
 function createSampler (options = {}) {
   return new Sampler(options)
@@ -12,6 +13,7 @@ module.exports.doc = createSampler
 module.exports.default = createSampler
 
 module.exports.Sampler = Sampler
+module.exports.errors = errors
 
 Object.defineProperty(module.exports, 'eventLoopUtilizationSupported', {
   value: util.eventLoopUtilizationSupported,

index.test-d.ts

@@ -1,20 +1,27 @@
-import { expectType, expectError } from 'tsd'
+import { expectType, expectError, expectAssignable } from 'tsd'
 import {
-  Sampler,
   createSampler,
+  eventLoopUtilizationSupported,
+  resourceUsageSupported,
+  gcFlagsSupported,
+  Sampler,
+  errors,
   CPUMetric,
   ResourceUsageMetric,
   EventLoopDelayMetric,
   EventLoopUtilizationMetric,
-  GCMetric,
-  eventLoopUtilizationSupported,
-  resourceUsageSupported,
-  gcFlagsSupported
+  GCMetric
 } from '.'
 
 expectType<Boolean>(eventLoopUtilizationSupported)
 expectType<Boolean>(resourceUsageSupported)
 expectType<Boolean>(gcFlagsSupported)
+expectAssignable<errors.NotSupportedError>(new errors.NotSupportedError())
+expectAssignable<'NotSupportedError'>(new errors.NotSupportedError().name)
+expectAssignable<'DOC_ERR_NOT_SUPPORTED'>(new errors.NotSupportedError().code)
+expectAssignable<errors.InvalidArgumentError>(new errors.InvalidArgumentError())
+expectAssignable<'InvalidArgumentError'>(new errors.InvalidArgumentError().name)
+expectAssignable<'DOC_ERR_INVALID_ARG'>(new errors.InvalidArgumentError().code)
 
 let sampler: Sampler
 

test/esm/namedExports.mjs

@@ -1,8 +1,9 @@
 import { strictEqual } from 'assert'
-import { doc, Sampler, eventLoopUtilizationSupported, resourceUsageSupported, gcFlagsSupported } from '../../index.js'
+import { doc, Sampler, errors, eventLoopUtilizationSupported, resourceUsageSupported, gcFlagsSupported } from '../../index.js'
 
 strictEqual(typeof doc, 'function')
 strictEqual(typeof Sampler, 'function')
+strictEqual(typeof errors, 'object')
 strictEqual(typeof eventLoopUtilizationSupported, 'boolean')
 strictEqual(typeof resourceUsageSupported, 'boolean')
 strictEqual(typeof gcFlagsSupported, 'boolean')

types/errors.d.ts

@@ -0,0 +1,15 @@
+declare namespace Errors {
+  /** An argument or option was invalid */
+  export class InvalidArgumentError extends Error {
+    name: 'InvalidArgumentError'
+    code: 'DOC_ERR_INVALID_ARG'
+  }
+
+  /** A metric is not supported */
+  export class NotSupportedError extends Error {
+    name: 'NotSupportedError'
+    code: 'DOC_ERR_NOT_SUPPORTED'
+  }
+}
+
+export = Errors