1 files changed, 112 insertions, 0 deletions

diff --git a/editors/code/src/ctx.ts b/editors/code/src/ctx.ts
new file mode 100644
index 000000000..a2a4e42a9
--- /dev/null
+++ b/editors/code/src/ctx.ts
@@ -0,0 +1,112 @@
+import * as vscode from 'vscode';
+import * as lc from 'vscode-languageclient';
+import { Config } from './config';
+import { createClient } from './client';
+
+export class Ctx {
+    readonly config: Config;
+    // Because we have "reload server" action, various listeners **will** face a
+    // situation where the client is not ready yet, and should be prepared to
+    // deal with it.
+    //
+    // Ideally, this should be replaced with async getter though.
+    client: lc.LanguageClient | null = null;
+    private extCtx: vscode.ExtensionContext;
+    private onDidRestartHooks: Array<(client: lc.LanguageClient) => void> = [];
+
+    constructor(extCtx: vscode.ExtensionContext) {
+        this.config = new Config(extCtx);
+        this.extCtx = extCtx;
+    }
+
+    async restartServer() {
+        let old = this.client;
+        if (old) {
+            await old.stop();
+        }
+        this.client = null;
+        const client = createClient(this.config);
+        this.pushCleanup(client.start());
+        await client.onReady();
+
+        this.client = client;
+        for (const hook of this.onDidRestartHooks) {
+            hook(client);
+        }
+    }
+
+    get activeRustEditor(): vscode.TextEditor | undefined {
+        const editor = vscode.window.activeTextEditor;
+        return editor && editor.document.languageId === 'rust'
+            ? editor
+            : undefined;
+    }
+
+    registerCommand(name: string, factory: (ctx: Ctx) => Cmd) {
+        const fullName = `rust-analyzer.${name}`;
+        const cmd = factory(this);
+        const d = vscode.commands.registerCommand(fullName, cmd);
+        this.pushCleanup(d);
+    }
+
+    overrideCommand(name: string, factory: (ctx: Ctx) => Cmd) {
+        const defaultCmd = `default:${name}`;
+        const override = factory(this);
+        const original = (...args: any[]) =>
+            vscode.commands.executeCommand(defaultCmd, ...args);
+        try {
+            const d = vscode.commands.registerCommand(
+                name,
+                async (...args: any[]) => {
+                    if (!(await override(...args))) {
+                        return await original(...args);
+                    }
+                },
+            );
+            this.pushCleanup(d);
+        } catch (_) {
+            vscode.window.showWarningMessage(
+                'Enhanced typing feature is disabled because of incompatibility with VIM extension, consider turning off rust-analyzer.enableEnhancedTyping: https://github.com/rust-analyzer/rust-analyzer/blob/master/docs/user/README.md#settings',
+            );
+        }
+    }
+
+    get subscriptions(): { dispose(): any }[] {
+        return this.extCtx.subscriptions;
+    }
+
+    pushCleanup(d: { dispose(): any }) {
+        this.extCtx.subscriptions.push(d);
+    }
+
+    onDidRestart(hook: (client: lc.LanguageClient) => void) {
+        this.onDidRestartHooks.push(hook);
+    }
+}
+
+export type Cmd = (...args: any[]) => any;
+
+export async function sendRequestWithRetry<R>(
+    client: lc.LanguageClient,
+    method: string,
+    param: any,
+    token?: vscode.CancellationToken,
+): Promise<R> {
+    for (const delay of [2, 4, 6, 8, 10, null]) {
+        try {
+            return await (token ? client.sendRequest(method, param, token) : client.sendRequest(method, param));
+        } catch (e) {
+            if (
+                e.code === lc.ErrorCodes.ContentModified &&
+                delay !== null
+            ) {
+                await sleep(10 * (1 << delay));
+                continue;
+            }
+            throw e;
+        }
+    }
+    throw 'unreachable';
+}
+
+const sleep = (ms: number) => new Promise(resolve => setTimeout(resolve, ms));