Source Control Sample
This sample implements a minimal source control provider. It shows how the source control experience in VS Code could be used to for example interact with code in JSFiddle.
VS Code API
Following VS Code APIs are demonstrated by this extension:
workspace.workspaceFolders
scm.createSourceControl
SourceControl
SourceControlResourceGroup
TextDocumentContentProvider
Running the Sample
Activate the extension by invoking the Open JSFiddle
command, specify the JSFiddle code, if no workspace folder is open, select a workspace folder. This invokes following 4 lines, which does the following:
- creates the custom source control provider associated with the workspace folder
- creates the source control resource group to later show the local changes to the files in the repository
- registers the
quickDiffProvider
, which implements the mapping between the documents in the remote repository and documents in the local folder.
this.jsFiddleScm = vscode.scm.createSourceControl('jsfiddle', 'JSFiddle #' + fiddle.slug, workspaceFolder.uri);
this.changedResources = this.jsFiddleScm.createResourceGroup('workingTree', 'Changes');
this.fiddleRepository = new FiddleRepository(workspaceFolder, fiddle.slug);
this.jsFiddleScm.quickDiffProvider = this.fiddleRepository;
See fiddleSourceControl.ts
for full code listing.
The three commands (command, roll-back and refresh) in the title of the source control view pane are configured this way:
"contributes": {
"commands": [
...
],
"menus": {
"scm/title": [
{
"command": "extension.source-control.commit",
"group": "navigation",
"when": "scmProvider == jsfiddle"
},
{
"command": "extension.source-control.discard",
"group": "navigation",
"when": "scmProvider == jsfiddle"
},
{
"command": "extension.source-control.refresh",
"group": "navigation",
"when": "scmProvider == jsfiddle"
},
{
"command": "extension.source-control.browse",
"when": "scmProvider == jsfiddle"
}
]
}
},
Note that the extension.source-control.browse
command is intentionally missing the "group": "navigation"
placement specification, which makes it show up under the [dot dot dot] button.
It is also worth noting that the sample extension needs to overcome reloading that VS Code triggers when a new workspace folder is added. This could be done either by writing a memo into the context.globalState
, or a configuration file into the workspace folder and reading it upon the next extension activation. The selected solution is to use .jsfiddle
configuration file as described below.
Status bar controls
The custom source control can add its own controls to the status bar. This typically needs to be refreshed every time a new version/branch is checked-out.
this.jsFiddleScm.statusBarCommands = [
{
"command": "extension.source-control.checkout",
"title": `↕ ${this.fiddle.slug} #${this.fiddle.version} / ${this.latestFiddleVersion}`,
"tooltip": "Checkout another version of this fiddle.",
}
];
The command extension.source-control.checkout
displays quick pick of the JSFiddle versions to check-out.
Populating changed files view
The extension listens to changes to files in the workspace folder and compares the new document text to the version originally checked out from the repository. When it differs, it creates vscode.SourceControlResourceState
for every changed document assigns such list to this.changedResources.resourceStates
, where the this.changedResources
was created earlier.
{
resourceUri: doc.uri,
command: {
title: "Show changes",
command: "vscode.diff",
arguments: [repositoryUri, doc.uri, `Checked-out version ↔ Local changes`],
tooltip: "Diff your changes"
}
}
where repositoryUri
is determined by
this.fiddleRepository.provideOriginalResource(doc.uri, null)
Quick diff
Both the regular diff (invoking the built-in vscode.diff
when user clicks on the changed resource in the source control view) and the Quick Diff (available in the left margin of the text editor) are rendered automatically by VS Code as long as the extension provides it with the content of the original document checked out from the repository. This is done by implementing a TextDocumentContentProvider
.
Source Control extension activation
A source control extensions gets activated either when a remote repository gets cloned
upon user request, or when a previously cloned workspace folder is open.
"activationEvents": [
"workspaceContains:.jsfiddle"
],
This extension implements the cloning using the extension.source-control.open
command.
This sample extension stores the source control configuration in the .jsfiddle
JSON file in the workspace folder root.
This is done by storing the .jsfiddle
configuration file into the WorkspaceFolder
just inserting the workspace folder via the vscode.workspace.updateWorkspaceFolders(...)
call, which seems to make the extension re-activate. Upon the re-activation, the initializeFromConfigurationFile()
function scans all WorkspaceFolder
s for the .jsfiddle
configuration files and re-creates the SourceControl
instances.
Multiple workspace folder support
Source control extension should support multiple workspace folders bound to different remote repositories.
Testing the sample
This sample can be tested on any JSFiddle with (e.g. u8B29/1
) or without (e.g. u8B29
) the version number specified. However, if you want to test committing code back to the repository, try typing in demo
instead of a real fiddle name, which lets you mock the repository without reading/writing from/to actual JSFiddle.