Add CodeAction support to show PSSA rule documentation

This corresponds to PSES PR:
PowerShell/PowerShellEditorServices#789

Currently this points to the PSSA development branch.  Maybe that should
point to the master branch.  Could be a setting I suppose but that seems
like overkill.

Author: rkeithhill

src/features/CodeActions.ts

@@ -6,13 +6,15 @@ import vscode = require("vscode");
 import { LanguageClient } from "vscode-languageclient";
 import Window = vscode.window;
 import { IFeature } from "../feature";
+import { ILogger } from "../logging";
 
 export class CodeActionsFeature implements IFeature {
-    private command: vscode.Disposable;
+    private applyEditsCommand: vscode.Disposable;
+    private showDocumentationCommand: vscode.Disposable;
     private languageClient: LanguageClient;
 
-    constructor() {
-        this.command = vscode.commands.registerCommand("PowerShell.ApplyCodeActionEdits", (edit: any) => {
+    constructor(private log: ILogger) {
+        this.applyEditsCommand = vscode.commands.registerCommand("PowerShell.ApplyCodeActionEdits", (edit: any) => {
             Window.activeTextEditor.edit((editBuilder) => {
                 editBuilder.replace(
                     new vscode.Range(
@@ -23,13 +25,34 @@ export class CodeActionsFeature implements IFeature {
                     edit.Text);
             });
         });
+
+        this.showDocumentationCommand =
+            vscode.commands.registerCommand("PowerShell.ShowCodeActionDocumentation", (ruleName: any) => {
+                this.showRuleDocumentation(ruleName);
+            });
     }
 
     public dispose() {
-        this.command.dispose();
+        this.applyEditsCommand.dispose();
+        this.showDocumentationCommand.dispose();
     }
 
     public setLanguageClient(languageclient: LanguageClient) {
         this.languageClient = languageclient;
     }
+
+    public showRuleDocumentation(ruleId: string) {
+        const pssaDocBaseURL = "https://github.com/PowerShell/PSScriptAnalyzer/blob/development/RuleDocumentation";
+
+        if (!ruleId) {
+            this.log.writeWarning("Cannot show documentation for code action, no ruleName was supplied.");
+            return;
+        }
+
+        if (ruleId.startsWith("PS")) {
+            ruleId = ruleId.substr(2);
+        }
+
+        vscode.commands.executeCommand("vscode.open", vscode.Uri.parse(pssaDocBaseURL + `/${ruleId}.md`));
+    }
 }

src/main.ts

@@ -128,7 +128,7 @@ export function activate(context: vscode.ExtensionContext): void {
         new PesterTestsFeature(sessionManager),
         new ExtensionCommandsFeature(logger),
         new SelectPSSARulesFeature(logger),
-        new CodeActionsFeature(),
+        new CodeActionsFeature(logger),
         new NewFileOrProjectFeature(),
         new DocumentFormatterFeature(logger, documentSelector),
         new RemoteFilesFeature(),