Add ability to customize what are extractable files

changelog.md

@@ -8,6 +8,9 @@
 
 ### Minor
 
+- Added the ability to customize what are extractable files, fixing [#10](https://github.com/jaydenseric/extract-files/issues/10) via [#11](https://github.com/jaydenseric/extract-files/pull/11):
+  - Added a new third parameter to the `extractFiles` function, for specifying a custom extractable file matcher.
+  - Export a new `isExtractableFile` function that is used as the default extractable file matcher for the `extractFiles` function. This can be used in a custom extractable file matcher implementation to match the default extractable files, along with additional custom files.
 - Setup [GitHub Sponsors funding](https://github.com/sponsors/jaydenseric):
   - Added `.github/funding.yml` to display a sponsor button in GitHub.
   - Added a `package.json` `funding` field to enable npm CLI funding features.

readme.md

@@ -28,7 +28,9 @@ See the [`extractFiles`](#function-extractfiles) documentation to get started.
 
 - [class ReactNativeFile](#class-reactnativefile)
 - [function extractFiles](#function-extractfiles)
+- [function isExtractableFile](#function-isextractablefile)
 - [type ExtractableFile](#type-extractablefile)
+- [type ExtractableFileMatcher](#type-extractablefilematcher)
 - [type ExtractFilesResult](#type-extractfilesresult)
 - [type ObjectPath](#type-objectpath)
 - [type ReactNativeFileSubstitute](#type-reactnativefilesubstitute)
@@ -65,6 +67,7 @@ Clones a value, recursively extracting [`File`](https://developer.mozilla.org/do
 | :-- | :-- | :-- |
 | `value` | \* | Value (typically an object tree) to extract files from. |
 | `path` | [ObjectPath](#type-objectpath)? = `''` | Prefix for object paths for extracted files. |
+| `isExtractableFile` | [ExtractableFileMatcher](#type-extractablefilematcher)? = [isExtractableFile](#function-isextractablefile) | The function used to identify extractable files. |
 
 **Returns:** [ExtractFilesResult](#type-extractfilesresult) — Result.
 
@@ -107,6 +110,28 @@ _Extract files from an object._
 
 ---
 
+### function isExtractableFile
+
+Checks if a value is an [extractable file](#type-extractablefile).
+
+**Type:** [ExtractableFileMatcher](#type-extractablefilematcher)
+
+| Parameter | Type | Description     |
+| :-------- | :--- | :-------------- |
+| `value`   | \*   | Value to check. |
+
+**Returns:** boolean — Is the value an [extractable file](#type-extractablefile).
+
+#### Examples
+
+_How to import._
+
+> ```js
+> import { isExtractableFile } from 'extract-files'
+> ```
+
+---
+
 ### type ExtractableFile
 
 An extractable file.
@@ -115,6 +140,36 @@ An extractable file.
 
 ---
 
+### type ExtractableFileMatcher
+
+A function that checks if a value is an extractable file.
+
+**Type:** Function
+
+| Parameter | Type | Description     |
+| :-------- | :--- | :-------------- |
+| `value`   | \*   | Value to check. |
+
+**Returns:** boolean — Is the value an extractable file.
+
+#### See
+
+- [`isExtractableFile`](#function-isextractablefile) is the default extractable file matcher.
+
+#### Examples
+
+_How to check for the default exactable files, as well as a custom type of file._
+
+> ```js
+> import { isExtractableFile } from 'extract-files'
+>
+> const isExtractableFileEnhanced = value =>
+>   isExtractableFile(value) ||
+>   (typeof CustomFile !== 'undefined' && value instanceof CustomFile)
+> ```
+
+---
+
 ### type ExtractFilesResult
 
 What [`extractFiles`](#function-extractfiles) returns.

src/extractFiles.mjs

@@ -1,4 +1,4 @@
-import { ReactNativeFile } from './ReactNativeFile.mjs'
+import { isExtractableFile as defaultIsExtractableFile } from './isExtractableFile.mjs'
 
 /**
  * Clones a value, recursively extracting
@@ -13,6 +13,7 @@ import { ReactNativeFile } from './ReactNativeFile.mjs'
  * @name extractFiles
  * @param {*} value Value (typically an object tree) to extract files from.
  * @param {ObjectPath} [path=''] Prefix for object paths for extracted files.
+ * @param {ExtractableFileMatcher} [isExtractableFile=isExtractableFile] The function used to identify extractable files.
  * @returns {ExtractFilesResult} Result.
  * @example <caption>Extract files from an object.</caption>
  * For the following:
@@ -48,7 +49,11 @@ import { ReactNativeFile } from './ReactNativeFile.mjs'
  * | `file1` | `['prefix.a', 'prefix.b.0']` |
  * | `file2` | `['prefix.b.1']`             |
  */
-export function extractFiles(value, path = '') {
+export function extractFiles(
+  value,
+  path = '',
+  isExtractableFile = defaultIsExtractableFile
+) {
   let clone
   const files = new Map()
 
@@ -66,11 +71,7 @@ export function extractFiles(value, path = '') {
     else files.set(file, paths)
   }
 
-  if (
-    (typeof File !== 'undefined' && value instanceof File) ||
-    (typeof Blob !== 'undefined' && value instanceof Blob) ||
-    value instanceof ReactNativeFile
-  ) {
+  if (isExtractableFile(value)) {
     clone = null
     addFile([path], value)
   } else {
@@ -83,14 +84,18 @@ export function extractFiles(value, path = '') {
       })
     else if (Array.isArray(value))
       clone = value.map((child, i) => {
-        const result = extractFiles(child, `${prefix}${i}`)
+        const result = extractFiles(child, `${prefix}${i}`, isExtractableFile)
         result.files.forEach(addFile)
         return result.clone
       })
     else if (value && value.constructor === Object) {
       clone = {}
       for (const i in value) {
-        const result = extractFiles(value[i], `${prefix}${i}`)
+        const result = extractFiles(
+          value[i],
+          `${prefix}${i}`,
+          isExtractableFile
+        )
         result.files.forEach(addFile)
         clone[i] = result.clone
       }

src/index.mjs

@@ -1,5 +1,6 @@
 export { extractFiles } from './extractFiles.mjs'
 export { ReactNativeFile } from './ReactNativeFile.mjs'
+export { isExtractableFile } from './isExtractableFile.mjs'
 
 /**
  * An extractable file.
@@ -8,6 +9,24 @@ export { ReactNativeFile } from './ReactNativeFile.mjs'
  * @type {File|Blob|ReactNativeFile}
  */
 
+/**
+ * A function that checks if a value is an extractable file.
+ * @kind typedef
+ * @name ExtractableFileMatcher
+ * @type {Function}
+ * @param {*} value Value to check.
+ * @returns {boolean} Is the value an extractable file.
+ * @see [`isExtractableFile`]{@link isExtractableFile} is the default extractable file matcher.
+ * @example <caption>How to check for the default exactable files, as well as a custom type of file.</caption>
+ * ```js
+ * import { isExtractableFile } from 'extract-files'
+ *
+ * const isExtractableFileEnhanced = value =>
+ *   isExtractableFile(value) ||
+ *   (typeof CustomFile !== 'undefined' && value instanceof CustomFile)
+ * ```
+ */
+
 /**
  * What [`extractFiles`]{@link extractFiles} returns.
  * @kind typedef

src/isExtractableFile.mjs

@@ -0,0 +1,18 @@
+import { ReactNativeFile } from './ReactNativeFile.mjs'
+
+/**
+ * Checks if a value is an [extractable file]{@link ExtractableFile}.
+ * @kind function
+ * @name isExtractableFile
+ * @type {ExtractableFileMatcher}
+ * @param {*} value Value to check.
+ * @returns {boolean} Is the value an [extractable file]{@link ExtractableFile}.
+ * @example <caption>How to import.</caption>
+ * ```js
+ * import { isExtractableFile } from 'extract-files'
+ * ```
+ */
+export const isExtractableFile = value =>
+  (typeof File !== 'undefined' && value instanceof File) ||
+  (typeof Blob !== 'undefined' && value instanceof Blob) ||
+  value instanceof ReactNativeFile