1 files changed, 148 insertions, 0 deletions
diff --git a/editors/code/src/bootstrap.ts b/editors/code/src/bootstrap.ts
new file mode 100644
index 00000000000..374c3b8144c
--- /dev/null
+++ b/editors/code/src/bootstrap.ts
@@ -0,0 +1,148 @@
+import * as vscode from "vscode";
+import * as os from "os";
+import { Config } from "./config";
+import { log, isValidExecutable } from "./util";
+import { PersistentState } from "./persistent_state";
+import { exec } from "child_process";
+
+export async function bootstrap(
+    context: vscode.ExtensionContext,
+    config: Config,
+    state: PersistentState
+): Promise<string> {
+    const path = await getServer(context, config, state);
+    if (!path) {
+        throw new Error(
+            "Rust Analyzer Language Server is not available. " +
+                "Please, ensure its [proper installation](https://rust-analyzer.github.io/manual.html#installation)."
+        );
+    }
+
+    log.info("Using server binary at", path);
+
+    if (!isValidExecutable(path)) {
+        if (config.serverPath) {
+            throw new Error(`Failed to execute ${path} --version. \`config.server.path\` or \`config.serverPath\` has been set explicitly.\
+            Consider removing this config or making a valid server binary available at that path.`);
+        } else {
+            throw new Error(`Failed to execute ${path} --version`);
+        }
+    }
+
+    return path;
+}
+
+async function patchelf(dest: vscode.Uri): Promise<void> {
+    await vscode.window.withProgress(
+        {
+            location: vscode.ProgressLocation.Notification,
+            title: "Patching rust-analyzer for NixOS",
+        },
+        async (progress, _) => {
+            const expression = `
+            {srcStr, pkgs ? import <nixpkgs> {}}:
+                pkgs.stdenv.mkDerivation {
+                    name = "rust-analyzer";
+                    src = /. + srcStr;
+                    phases = [ "installPhase" "fixupPhase" ];
+                    installPhase = "cp $src $out";
+                    fixupPhase = ''
+                    chmod 755 $out
+                    patchelf --set-interpreter "$(cat $NIX_CC/nix-support/dynamic-linker)" $out
+                    '';
+                }
+            `;
+            const origFile = vscode.Uri.file(dest.fsPath + "-orig");
+            await vscode.workspace.fs.rename(dest, origFile, { overwrite: true });
+            try {
+                progress.report({ message: "Patching executable", increment: 20 });
+                await new Promise((resolve, reject) => {
+                    const handle = exec(
+                        `nix-build -E - --argstr srcStr '${origFile.fsPath}' -o '${dest.fsPath}'`,
+                        (err, stdout, stderr) => {
+                            if (err != null) {
+                                reject(Error(stderr));
+                            } else {
+                                resolve(stdout);
+                            }
+                        }
+                    );
+                    handle.stdin?.write(expression);
+                    handle.stdin?.end();
+                });
+            } finally {
+                await vscode.workspace.fs.delete(origFile);
+            }
+        }
+    );
+}
+
+async function getServer(
+    context: vscode.ExtensionContext,
+    config: Config,
+    state: PersistentState
+): Promise<string | undefined> {
+    const explicitPath = serverPath(config);
+    if (explicitPath) {
+        if (explicitPath.startsWith("~/")) {
+            return os.homedir() + explicitPath.slice("~".length);
+        }
+        return explicitPath;
+    }
+    if (config.package.releaseTag === null) return "rust-analyzer";
+
+    const ext = process.platform === "win32" ? ".exe" : "";
+    const bundled = vscode.Uri.joinPath(context.extensionUri, "server", `rust-analyzer${ext}`);
+    const bundledExists = await vscode.workspace.fs.stat(bundled).then(
+        () => true,
+        () => false
+    );
+    if (bundledExists) {
+        let server = bundled;
+        if (await isNixOs()) {
+            await vscode.workspace.fs.createDirectory(config.globalStorageUri).then();
+            const dest = vscode.Uri.joinPath(config.globalStorageUri, `rust-analyzer${ext}`);
+            let exists = await vscode.workspace.fs.stat(dest).then(
+                () => true,
+                () => false
+            );
+            if (exists && config.package.version !== state.serverVersion) {
+                await vscode.workspace.fs.delete(dest);
+                exists = false;
+            }
+            if (!exists) {
+                await vscode.workspace.fs.copy(bundled, dest);
+                await patchelf(dest);
+            }
+            server = dest;
+        }
+        await state.updateServerVersion(config.package.version);
+        return server.fsPath;
+    }
+
+    await state.updateServerVersion(undefined);
+    await vscode.window.showErrorMessage(
+        "Unfortunately we don't ship binaries for your platform yet. " +
+            "You need to manually clone the rust-analyzer repository and " +
+            "run `cargo xtask install --server` to build the language server from sources. " +
+            "If you feel that your platform should be supported, please create an issue " +
+            "about that [here](https://github.com/rust-lang/rust-analyzer/issues) and we " +
+            "will consider it."
+    );
+    return undefined;
+}
+function serverPath(config: Config): string | null {
+    return process.env.__RA_LSP_SERVER_DEBUG ?? config.serverPath;
+}
+
+async function isNixOs(): Promise<boolean> {
+    try {
+        const contents = (
+            await vscode.workspace.fs.readFile(vscode.Uri.file("/etc/os-release"))
+        ).toString();
+        const idString = contents.split("\n").find((a) => a.startsWith("ID=")) || "ID=linux";
+        return idString.indexOf("nixos") !== -1;
+    } catch {
+        return false;
+    }
+}