[vscode] parse view contribution "when" clause context

packages/core/src/browser/context-key-service.ts

@@ -22,6 +22,7 @@ export interface ContextKey<T> {
     reset(): void;
     get(): T | undefined;
 }
+
 export namespace ContextKey {
     // tslint:disable-next-line:no-any
     export const None: ContextKey<any> = Object.freeze({
@@ -54,4 +55,11 @@ export class ContextKeyService {
         return true;
     }
 
+    /**
+     * It should be implemented by an extension, e.g. by the monaco extension.
+     */
+    parseKeys(expression: string): Set<string> {
+        return new Set<string>();
+    }
+
 }

packages/monaco/src/browser/monaco-context-key-service.ts

@@ -58,4 +58,8 @@ export class MonacoContextKeyService extends ContextKeyService {
         return expression;
     }
 
+    parseKeys(expression: string): Set<string> {
+        return new Set<string>(monaco.contextkey.ContextKeyExpr.deserialize(expression).keys());
+    }
+
 }

packages/monaco/src/typings/monaco/index.d.ts

@@ -1119,6 +1119,7 @@ declare module monaco.contextKeyService {
 
 declare module monaco.contextkey {
     export class ContextKeyExpr {
+        keys(): string[];
         static deserialize(when: string): ContextKeyExpr;
     }
 }

packages/plugin-ext/src/main/browser/view/plugin-view-registry.ts

@@ -89,6 +89,7 @@ export class PluginViewRegistry implements FrontendApplicationContribution {
     private readonly views = new Map<string, [string, View]>();
     private readonly viewContainers = new Map<string, [string, ViewContainerTitleOptions]>();
     private readonly containerViews = new Map<string, string[]>();
+    private readonly viewClauseContexts = new Map<string, Set<string>>();
 
     private readonly viewDataProviders = new Map<string, ViewDataProvider>();
     private readonly viewDataState = new Map<string, object>();
@@ -138,10 +139,8 @@ export class PluginViewRegistry implements FrontendApplicationContribution {
         });
         this.contextKeyService.onDidChange(e => {
             for (const [, view] of this.views.values()) {
-                if (view.when === undefined) {
-                    continue;
-                }
-                if (e.affects(new Set([view.when]))) {
+                const clauseContext = this.viewClauseContexts.get(view.id);
+                if (clauseContext && e.affects(clauseContext)) {
                     this.updateViewVisibility(view.id);
                 }
             }
@@ -231,6 +230,9 @@ export class PluginViewRegistry implements FrontendApplicationContribution {
         const containerViews = this.containerViews.get(viewContainerId) || [];
         containerViews.push(view.id);
         this.containerViews.set(viewContainerId, containerViews);
+        if (view.when) {
+            this.viewClauseContexts.set(view.id, this.contextKeyService.parseKeys(view.when));
+        }
         this.quickView.registerItem({
             label: view.name,
             open: async () => {