Add new interface git.showBuffer to allow using git.show with bin…

…ary file content.

Closes #921

simple-git/readme.md

@@ -209,7 +209,6 @@ For type details of the response for each of the tasks, please see the [TypeScri
 | `.rmKeepLocal([fileA, ...], handlerFn)`              | removes files from source control but leaves them on disk                                                                                                                                                                                                                                                                                                                                                                    |
 | `.tag(args[], handlerFn)`                            | Runs any supported [git tag](https://git-scm.com/docs/git-tag) commands with arguments passed as an array of strings .                                                                                                                                                                                                                                                                                                       |
 | `.tags([options, ] handlerFn)`                       | list all tags, use the optional [options](#how-to-specify-options) object to set any options allows by the [git tag](https://git-scm.com/docs/git-tag) command. Tags will be sorted by semantic version number by default, for git versions 2.7 and above, use the `--sort` option to set a custom sort.                                                                                                                     |
-| `.show([options], handlerFn)`                        | Show various types of objects, for example the file content at a certain commit. `options` is the single value string or array of string commands you want to run                                                                                                                                                                                                                                                            |
 
 ## git apply
 
@@ -376,6 +375,11 @@ For type details of the response for each of the tasks, please see the [TypeScri
 -  `.checkIsRepo('bare')` gets whether the current working directory is within a bare git repo (see either [git clone --bare](https://git-scm.com/docs/git-clone#Documentation/git-clone.txt---bare) or [git init --bare](https://git-scm.com/docs/git-init#Documentation/git-init.txt---bare)).
 -  `.checkIsRepo('root')` gets whether the current working directory is the root directory for a repo (sub-directories will return false).
 
+## git show
+
+- `.show(options)` show various types of objects for example the file content at a certain commit. `options` is the single value string or any [options](#how-to-specify-options) supported by the [git show](https://git-scm.com/docs/git-show) command.
+- `.showBuffer(options)` same as the `.show` api, but returns the Buffer content directly to allow for showing binary file content.
+
 ## git status
 
 -  `.status([options])` gets the status of the current repo, resulting in a [StatusResult](https://github.com/steveukx/git-js/blob/main/simple-git/typings/response.d.ts). Additional arguments

simple-git/src/git.js

@@ -563,19 +563,6 @@ Git.prototype.revparse = function () {
    );
 };
 
-/**
- * Show various types of objects, for example the file at a certain commit
- *
- * @param {string[]} [options]
- * @param {Function} [then]
- */
-Git.prototype.show = function (options, then) {
-   return this._runTask(
-      straightThroughStringTask(['show', ...getTrailingOptions(arguments, 1)]),
-      trailingFunctionArgument(arguments)
-   );
-};
-
 /**
  */
 Git.prototype.clean = function (mode, options, then) {

simple-git/src/lib/simple-git-api.ts

@@ -10,6 +10,7 @@ import { initTask } from './tasks/init';
 import log from './tasks/log';
 import { mergeTask } from './tasks/merge';
 import { pushTask } from './tasks/push';
+import show from './tasks/show';
 import { statusTask } from './tasks/status';
 import { configurationErrorTask, straightThroughStringTask } from './tasks/task';
 import version from './tasks/version';
@@ -138,4 +139,13 @@ export class SimpleGitApi implements SimpleGitBase {
    }
 }
 
-Object.assign(SimpleGitApi.prototype, checkout(), commit(), config(), grep(), log(), version());
+Object.assign(
+   SimpleGitApi.prototype,
+   checkout(),
+   commit(),
+   config(),
+   grep(),
+   log(),
+   show(),
+   version()
+);

simple-git/src/lib/tasks/show.ts

@@ -0,0 +1,28 @@
+import { SimpleGit } from '../../../typings';
+import { SimpleGitApi } from '../simple-git-api';
+import { getTrailingOptions, trailingFunctionArgument } from '../utils';
+import { straightThroughBufferTask, straightThroughStringTask } from './task';
+
+export default function (): Pick<SimpleGit, 'showBuffer' | 'show'> {
+   return {
+      showBuffer(this: SimpleGitApi) {
+         const commands = ['show', ...getTrailingOptions(arguments, 1)];
+         if (!commands.includes('--binary')) {
+            commands.splice(1, 0, '--binary');
+         }
+
+         return this._runTask(
+            straightThroughBufferTask(commands),
+            trailingFunctionArgument(arguments)
+         );
+      },
+
+      show(this: SimpleGitApi) {
+         const commands = ['show', ...getTrailingOptions(arguments, 1)];
+         return this._runTask(
+            straightThroughStringTask(commands),
+            trailingFunctionArgument(arguments)
+         );
+      },
+   };
+}

simple-git/test/unit/show.spec.ts

@@ -11,6 +11,15 @@ describe('show', () => {
       callback = jest.fn();
    });
 
+   it('permits binary responses', async () => {
+      const task = git.showBuffer('HEAD:img.jpg');
+      await closeWithSuccess('some response');
+      const result = await task;
+
+      expect(result).toEqual(expect.any(Buffer));
+      expect(result.toString('utf8')).toEqual('some response');
+   });
+
    it('passes the response through without editing', async () => {
       const { stdOut } = showAbbrevCommitSingleFile();
 

simple-git/typings/simple-git.d.ts

@@ -899,6 +899,8 @@ export interface SimpleGit extends SimpleGitBase {
 
    show(callback?: types.SimpleGitTaskCallback<string>): Response<string>;
 
+   showBuffer(option: string | types.TaskOptions): Response<Buffer>;
+
    /**
     * @deprecated
     *