6 files changed, 112 insertions, 89 deletions

diff --git a/editors/code/package.json b/editors/code/package.json
index eb5748515..37e083220 100644
--- a/editors/code/package.json
+++ b/editors/code/package.json
@@ -73,10 +73,18 @@
                         "type": "string"
                     },
                     "args": {
-                        "type": "array"
+                        "type": "array",
+                        "items": {
+                            "type": "string"
+                        }
                     },
                     "env": {
-                        "type": "object"
+                        "type": "object",
+                        "patternProperties": {
+                            ".+": {
+                                "type": "string"
+                            }
+                        }
                     }
                 }
             }
@@ -325,6 +333,11 @@
                     "default": true,
                     "description": "Whether to show inlay type hints"
                 },
+                "rust-analyzer.inlayHints.chainingHints": {
+                    "type": "boolean",
+                    "default": true,
+                    "description": "Whether to show inlay type hints for method chains"
+                },
                 "rust-analyzer.inlayHints.parameterHints": {
                     "type": "boolean",
                     "default": true,
diff --git a/editors/code/src/client.ts b/editors/code/src/client.ts
index 08d821dd0..98f2f232f 100644
--- a/editors/code/src/client.ts
+++ b/editors/code/src/client.ts
@@ -32,6 +32,7 @@ export async function createClient(config: Config, serverPath: string): Promise<
 
             inlayHintsType: config.inlayHints.typeHints,
             inlayHintsParameter: config.inlayHints.parameterHints,
+            inlayHintsChaining: config.inlayHints.chainingHints,
             inlayHintsMaxLength: config.inlayHints.maxLength,
 
             cargoWatchEnable: cargoWatchOpts.enable,
@@ -99,8 +100,10 @@ export async function createClient(config: Config, serverPath: string): Promise<
     // Note that while the CallHierarchyFeature is stable the LSP protocol is not.
     res.registerFeature(new CallHierarchyFeature(res));
 
-    if (config.highlightingSemanticTokens) {
-        res.registerFeature(new SemanticTokensFeature(res));
+    if (config.package.enableProposedApi) {
+        if (config.highlightingSemanticTokens) {
+            res.registerFeature(new SemanticTokensFeature(res));
+        }
     }
 
     return res;
diff --git a/editors/code/src/config.ts b/editors/code/src/config.ts
index be5296fcf..637aea27d 100644
--- a/editors/code/src/config.ts
+++ b/editors/code/src/config.ts
@@ -1,29 +1,10 @@
 import * as vscode from 'vscode';
 import { log } from "./util";
 
-export interface InlayHintOptions {
-    typeHints: boolean;
-    parameterHints: boolean;
-    maxLength: number | null;
-}
-
-export interface CargoWatchOptions {
-    enable: boolean;
-    arguments: string[];
-    command: string;
-    allTargets: boolean;
-}
-
-export interface CargoFeatures {
-    noDefaultFeatures: boolean;
-    allFeatures: boolean;
-    features: string[];
-    loadOutDirsFromCheck: boolean;
-}
-
 export type UpdatesChannel = "stable" | "nightly";
 
 export const NIGHTLY_TAG = "nightly";
+
 export class Config {
     readonly extensionId = "matklad.rust-analyzer";
 
@@ -38,37 +19,30 @@ export class Config {
     ]
         .map(opt => `${this.rootSection}.${opt}`);
 
-    readonly packageJsonVersion: string = vscode
-        .extensions
-        .getExtension(this.extensionId)!
-        .packageJSON
-        .version;
-
-    readonly releaseTag: string | undefined = vscode
-        .extensions
-        .getExtension(this.extensionId)!
-        .packageJSON
-        .releaseTag ?? undefined;
+    readonly package: {
+        version: string;
+        releaseTag: string | undefined;
+        enableProposedApi: boolean | undefined;
+    } = vscode.extensions.getExtension(this.extensionId)!.packageJSON;
 
-    private cfg!: vscode.WorkspaceConfiguration;
+    readonly globalStoragePath: string;
 
-    constructor(private readonly ctx: vscode.ExtensionContext) {
-        vscode.workspace.onDidChangeConfiguration(this.onConfigChange, this, ctx.subscriptions);
-        this.refreshConfig();
+    constructor(ctx: vscode.ExtensionContext) {
+        this.globalStoragePath = ctx.globalStoragePath;
+        vscode.workspace.onDidChangeConfiguration(this.onDidChangeConfiguration, this, ctx.subscriptions);
+        this.refreshLogging();
     }
 
-    private refreshConfig() {
-        this.cfg = vscode.workspace.getConfiguration(this.rootSection);
-        const enableLogging = this.cfg.get("trace.extension") as boolean;
-        log.setEnabled(enableLogging);
+    private refreshLogging() {
+        log.setEnabled(this.traceExtension);
         log.debug(
-            "Extension version:", this.packageJsonVersion,
+            "Extension version:", this.package.version,
             "using configuration:", this.cfg
         );
     }
 
-    private async onConfigChange(event: vscode.ConfigurationChangeEvent) {
-        this.refreshConfig();
+    private async onDidChangeConfiguration(event: vscode.ConfigurationChangeEvent) {
+        this.refreshLogging();
 
         const requiresReloadOpt = this.requiresReloadOpts.find(
             opt => event.affectsConfiguration(opt)
@@ -86,49 +60,54 @@ export class Config {
         }
     }
 
-    get globalStoragePath(): string { return this.ctx.globalStoragePath; }
-
     // We don't do runtime config validation here for simplicity. More on stackoverflow:
     // https://stackoverflow.com/questions/60135780/what-is-the-best-way-to-type-check-the-configuration-for-vscode-extension
 
-    get serverPath() { return this.cfg.get("serverPath") as null | string; }
-    get channel() { return this.cfg.get<"stable" | "nightly">("updates.channel")!; }
-    get askBeforeDownload() { return this.cfg.get("updates.askBeforeDownload") as boolean; }
-    get highlightingSemanticTokens() { return this.cfg.get("highlighting.semanticTokens") as boolean; }
-    get highlightingOn() { return this.cfg.get("highlightingOn") as boolean; }
-    get rainbowHighlightingOn() { return this.cfg.get("rainbowHighlightingOn") as boolean; }
-    get lruCapacity() { return this.cfg.get("lruCapacity") as null | number; }
-    get inlayHints(): InlayHintOptions {
+    private get cfg(): vscode.WorkspaceConfiguration {
+        return vscode.workspace.getConfiguration(this.rootSection);
+    }
+
+    get serverPath() { return this.cfg.get<null | string>("serverPath")!; }
+    get channel() { return this.cfg.get<UpdatesChannel>("updates.channel")!; }
+    get askBeforeDownload() { return this.cfg.get<boolean>("updates.askBeforeDownload")!; }
+    get highlightingSemanticTokens() { return this.cfg.get<boolean>("highlighting.semanticTokens")!; }
+    get highlightingOn() { return this.cfg.get<boolean>("highlightingOn")!; }
+    get rainbowHighlightingOn() { return this.cfg.get<boolean>("rainbowHighlightingOn")!; }
+    get lruCapacity() { return this.cfg.get<null | number>("lruCapacity")!; }
+    get excludeGlobs() { return this.cfg.get<string[]>("excludeGlobs")!; }
+    get useClientWatching() { return this.cfg.get<boolean>("useClientWatching")!; }
+    get featureFlags() { return this.cfg.get<Record<string, boolean>>("featureFlags")!; }
+    get rustfmtArgs() { return this.cfg.get<string[]>("rustfmtArgs")!; }
+    get loadOutDirsFromCheck() { return this.cfg.get<boolean>("loadOutDirsFromCheck")!; }
+    get traceExtension() { return this.cfg.get<boolean>("trace.extension")!; }
+
+    // for internal use
+    get withSysroot() { return this.cfg.get<boolean>("withSysroot", true)!; }
+
+    get inlayHints() {
         return {
-            typeHints: this.cfg.get("inlayHints.typeHints") as boolean,
-            parameterHints: this.cfg.get("inlayHints.parameterHints") as boolean,
-            maxLength: this.cfg.get("inlayHints.maxLength") as null | number,
+            typeHints: this.cfg.get<boolean>("inlayHints.typeHints")!,
+            parameterHints: this.cfg.get<boolean>("inlayHints.parameterHints")!,
+            chainingHints: this.cfg.get<boolean>("inlayHints.chainingHints")!,
+            maxLength: this.cfg.get<null | number>("inlayHints.maxLength")!,
         };
     }
-    get excludeGlobs() { return this.cfg.get("excludeGlobs") as string[]; }
-    get useClientWatching() { return this.cfg.get("useClientWatching") as boolean; }
-    get featureFlags() { return this.cfg.get("featureFlags") as Record<string, boolean>; }
-    get rustfmtArgs() { return this.cfg.get("rustfmtArgs") as string[]; }
-    get loadOutDirsFromCheck() { return this.cfg.get("loadOutDirsFromCheck") as boolean; }
 
-    get cargoWatchOptions(): CargoWatchOptions {
+    get cargoWatchOptions() {
         return {
-            enable: this.cfg.get("cargo-watch.enable") as boolean,
-            arguments: this.cfg.get("cargo-watch.arguments") as string[],
-            allTargets: this.cfg.get("cargo-watch.allTargets") as boolean,
-            command: this.cfg.get("cargo-watch.command") as string,
+            enable: this.cfg.get<boolean>("cargo-watch.enable")!,
+            arguments: this.cfg.get<string[]>("cargo-watch.arguments")!,
+            allTargets: this.cfg.get<boolean>("cargo-watch.allTargets")!,
+            command: this.cfg.get<string>("cargo-watch.command")!,
         };
     }
 
-    get cargoFeatures(): CargoFeatures {
+    get cargoFeatures() {
         return {
-            noDefaultFeatures: this.cfg.get("cargoFeatures.noDefaultFeatures") as boolean,
-            allFeatures: this.cfg.get("cargoFeatures.allFeatures") as boolean,
-            features: this.cfg.get("cargoFeatures.features") as string[],
-            loadOutDirsFromCheck: this.cfg.get("cargoFeatures.loadOutDirsFromCheck") as boolean,
+            noDefaultFeatures: this.cfg.get<boolean>("cargoFeatures.noDefaultFeatures")!,
+            allFeatures: this.cfg.get<boolean>("cargoFeatures.allFeatures")!,
+            features: this.cfg.get<string[]>("cargoFeatures.features")!,
+            loadOutDirsFromCheck: this.cfg.get<boolean>("cargoFeatures.loadOutDirsFromCheck")!,
         };
     }
-
-    // for internal use
-    get withSysroot() { return this.cfg.get("withSysroot", true) as boolean; }
 }
diff --git a/editors/code/src/inlay_hints.ts b/editors/code/src/inlay_hints.ts
index 17d0dfa33..542d1f367 100644
--- a/editors/code/src/inlay_hints.ts
+++ b/editors/code/src/inlay_hints.ts
@@ -10,7 +10,11 @@ export function activateInlayHints(ctx: Ctx) {
     const maybeUpdater = {
         updater: null as null | HintsUpdater,
         onConfigChange() {
-            if (!ctx.config.inlayHints.typeHints && !ctx.config.inlayHints.parameterHints) {
+            if (
+                !ctx.config.inlayHints.typeHints &&
+                !ctx.config.inlayHints.parameterHints &&
+                !ctx.config.inlayHints.chainingHints
+            ) {
                 return this.dispose();
             }
             if (!this.updater) this.updater = new HintsUpdater(ctx);
@@ -63,6 +67,22 @@ const paramHints = {
     }
 };
 
+const chainingHints = {
+    decorationType: vscode.window.createTextEditorDecorationType({
+        after: {
+            color: new vscode.ThemeColor('rust_analyzer.inlayHint'),
+            fontStyle: "normal",
+        }
+    }),
+
+    toDecoration(hint: ra.InlayHint.ChainingHint, conv: lc.Protocol2CodeConverter): vscode.DecorationOptions {
+        return {
+            range: conv.asRange(hint.range),
+            renderOptions: { after: { contentText: ` ${hint.label}` } }
+        };
+    }
+};
+
 class HintsUpdater implements Disposable {
     private sourceFiles = new Map<string, RustSourceFile>(); // map Uri -> RustSourceFile
     private readonly disposables: Disposable[] = [];
@@ -95,7 +115,7 @@ class HintsUpdater implements Disposable {
 
     dispose() {
         this.sourceFiles.forEach(file => file.inlaysRequest?.cancel());
-        this.ctx.visibleRustEditors.forEach(editor => this.renderDecorations(editor, { param: [], type: [] }));
+        this.ctx.visibleRustEditors.forEach(editor => this.renderDecorations(editor, { param: [], type: [], chaining: [] }));
         this.disposables.forEach(d => d.dispose());
     }
 
@@ -154,10 +174,11 @@ class HintsUpdater implements Disposable {
     private renderDecorations(editor: RustEditor, decorations: InlaysDecorations) {
         editor.setDecorations(typeHints.decorationType, decorations.type);
         editor.setDecorations(paramHints.decorationType, decorations.param);
+        editor.setDecorations(chainingHints.decorationType, decorations.chaining);
     }
 
     private hintsToDecorations(hints: ra.InlayHint[]): InlaysDecorations {
-        const decorations: InlaysDecorations = { type: [], param: [] };
+        const decorations: InlaysDecorations = { type: [], param: [], chaining: [] };
         const conv = this.ctx.client.protocol2CodeConverter;
 
         for (const hint of hints) {
@@ -170,6 +191,10 @@ class HintsUpdater implements Disposable {
                     decorations.param.push(paramHints.toDecoration(hint, conv));
                     continue;
                 }
+                case ra.InlayHint.Kind.ChainingHint: {
+                    decorations.chaining.push(chainingHints.toDecoration(hint, conv));
+                    continue;
+                }
             }
         }
         return decorations;
@@ -196,6 +221,7 @@ class HintsUpdater implements Disposable {
 interface InlaysDecorations {
     type: vscode.DecorationOptions[];
     param: vscode.DecorationOptions[];
+    chaining: vscode.DecorationOptions[];
 }
 
 interface RustSourceFile {
diff --git a/editors/code/src/main.ts b/editors/code/src/main.ts
index 5d2da9a76..de27d9535 100644
--- a/editors/code/src/main.ts
+++ b/editors/code/src/main.ts
@@ -110,9 +110,9 @@ async function bootstrap(config: Config, state: PersistentState): Promise<string
 }
 
 async function bootstrapExtension(config: Config, state: PersistentState): Promise<void> {
-    if (config.releaseTag === undefined) return;
+    if (config.package.releaseTag === undefined) return;
     if (config.channel === "stable") {
-        if (config.releaseTag === NIGHTLY_TAG) {
+        if (config.package.releaseTag === NIGHTLY_TAG) {
             vscode.window.showWarningMessage(`You are running a nightly version of rust-analyzer extension.
 To switch to stable, uninstall the extension and re-install it from the marketplace`);
         }
@@ -185,10 +185,10 @@ async function getServer(config: Config, state: PersistentState): Promise<string
         }
         return explicitPath;
     };
-    if (config.releaseTag === undefined) return "rust-analyzer";
+    if (config.package.releaseTag === undefined) return "rust-analyzer";
 
     let binaryName: string | undefined = undefined;
-    if (process.arch === "x64" || process.arch === "x32") {
+    if (process.arch === "x64" || process.arch === "ia32") {
         if (process.platform === "linux") binaryName = "rust-analyzer-linux";
         if (process.platform === "darwin") binaryName = "rust-analyzer-mac";
         if (process.platform === "win32") binaryName = "rust-analyzer-windows.exe";
@@ -211,21 +211,21 @@ async function getServer(config: Config, state: PersistentState): Promise<string
         await state.updateServerVersion(undefined);
     }
 
-    if (state.serverVersion === config.packageJsonVersion) return dest;
+    if (state.serverVersion === config.package.version) return dest;
 
     if (config.askBeforeDownload) {
         const userResponse = await vscode.window.showInformationMessage(
-            `Language server version ${config.packageJsonVersion} for rust-analyzer is not installed.`,
+            `Language server version ${config.package.version} for rust-analyzer is not installed.`,
             "Download now"
         );
         if (userResponse !== "Download now") return dest;
     }
 
-    const release = await fetchRelease(config.releaseTag);
+    const release = await fetchRelease(config.package.releaseTag);
     const artifact = release.assets.find(artifact => artifact.name === binaryName);
     assert(!!artifact, `Bad release: ${JSON.stringify(release)}`);
 
     await download(artifact.browser_download_url, dest, "Downloading rust-analyzer server", { mode: 0o755 });
-    await state.updateServerVersion(config.packageJsonVersion);
+    await state.updateServerVersion(config.package.version);
     return dest;
 }
diff --git a/editors/code/src/rust-analyzer-api.ts b/editors/code/src/rust-analyzer-api.ts
index 9846f7343..400ac3714 100644
--- a/editors/code/src/rust-analyzer-api.ts
+++ b/editors/code/src/rust-analyzer-api.ts
@@ -86,12 +86,13 @@ export interface Runnable {
 }
 export const runnables = request<RunnablesParams, Vec<Runnable>>("runnables");
 
-export type InlayHint = InlayHint.TypeHint | InlayHint.ParamHint;
+export type InlayHint = InlayHint.TypeHint | InlayHint.ParamHint | InlayHint.ChainingHint;
 
 export namespace InlayHint {
     export const enum Kind {
         TypeHint = "TypeHint",
         ParamHint = "ParameterHint",
+        ChainingHint = "ChainingHint",
     }
     interface Common {
         range: lc.Range;
@@ -99,6 +100,7 @@ export namespace InlayHint {
     }
     export type TypeHint = Common & { kind: Kind.TypeHint };
     export type ParamHint = Common & { kind: Kind.ParamHint };
+    export type ChainingHint = Common & { kind: Kind.ChainingHint };
 }
 export interface InlayHintsParams {
     textDocument: lc.TextDocumentIdentifier;