fix Start Code Analysis: use correct binary paths for ReScript v12+

CHANGELOG.md

@@ -14,6 +14,7 @@
 
 #### :bug: Bug fix
 
+- Fix binary path resolution for ReScript v12+ projects. The extension now correctly locates binaries via `@rescript/{platform}/bin.js`.
 - Take namespace into account for incremental cleanup. https://github.com/rescript-lang/rescript-vscode/pull/1164
 - Potential race condition in incremental compilation. https://github.com/rescript-lang/rescript-vscode/pull/1167
 - Fix extension crash triggered by incremental compilation. https://github.com/rescript-lang/rescript-vscode/pull/1169

client/src/commands/code_analysis.ts

@@ -14,10 +14,12 @@ import {
   OutputChannel,
   StatusBarItem,
 } from "vscode";
+import * as semver from "semver";
 import {
   findProjectRootOfFileInDir,
   getBinaryPath,
   NormalizedPath,
+  findReScriptVersion,
 } from "../utils";
 
 export let statusBarItem = {
@@ -216,12 +218,20 @@ export const runCodeAnalysisWithReanalyze = (
     currentDocument.uri.fsPath,
   );
 
-  // This little weird lookup is because in the legacy setup reanalyze needs to be
-  // run from the analysis binary, whereas in the new setup it's run from the tools
-  // binary.
-  let binaryPath =
-    getBinaryPath("rescript-tools.exe", projectRootPath) ??
-    getBinaryPath("rescript-editor-analysis.exe");
+  // v12+: reanalyze is run from rescript-tools.exe
+  // Legacy: reanalyze is run from rescript-editor-analysis.exe
+  const rescriptVersion = findReScriptVersion(projectRootPath);
+  const isReScript12OrHigher =
+    rescriptVersion != null &&
+    semver.valid(rescriptVersion) &&
+    semver.gte(rescriptVersion, "12.0.0");
+
+  let binaryPath: string | null;
+  if (isReScript12OrHigher) {
+    binaryPath = getBinaryPath("rescript-tools.exe", projectRootPath);
+  } else {
+    binaryPath = getBinaryPath("rescript-editor-analysis.exe", projectRootPath);
+  }
 
   if (binaryPath === null) {
     window.showErrorMessage("Binary executable not found.");

client/src/utils-legacy.ts

@@ -0,0 +1,59 @@
+/**
+ * Legacy binary finding for ReScript < 12.
+ * This code is kept separate to avoid polluting the main utils with pre-v12 complexity.
+ */
+
+import * as fs from "fs";
+import * as path from "path";
+import { NormalizedPath } from "./utils";
+
+type binaryName = "rescript-editor-analysis.exe" | "rescript-tools.exe";
+
+// Legacy format: no hyphen (e.g., "darwinarm64")
+const platformDir =
+  process.arch === "arm64" ? process.platform + process.arch : process.platform;
+
+const getLegacyBinaryDevPath = (b: binaryName) =>
+  path.join(path.dirname(__dirname), "..", "analysis", b);
+
+export const getLegacyBinaryProdPath = (b: binaryName) =>
+  path.join(
+    path.dirname(__dirname),
+    "..",
+    "server",
+    "analysis_binaries",
+    platformDir,
+    b,
+  );
+
+/**
+ * Finds binaries for ReScript < 12 using old path structure.
+ * Tries project binary first, then falls back to builtin binaries.
+ */
+export const getBinaryPathLegacy = (
+  projectRootPath: NormalizedPath | null,
+  binaryName: binaryName,
+): string | null => {
+  // Try project binary first
+  if (projectRootPath != null) {
+    const binaryFromCompilerPackage = path.join(
+      projectRootPath,
+      "node_modules",
+      "rescript",
+      platformDir,
+      binaryName,
+    );
+    if (fs.existsSync(binaryFromCompilerPackage)) {
+      return binaryFromCompilerPackage;
+    }
+  }
+
+  // Fall back to builtin binaries
+  if (fs.existsSync(getLegacyBinaryDevPath(binaryName))) {
+    return getLegacyBinaryDevPath(binaryName);
+  } else if (fs.existsSync(getLegacyBinaryProdPath(binaryName))) {
+    return getLegacyBinaryProdPath(binaryName);
+  }
+
+  return null;
+};

client/src/utils.ts

@@ -2,6 +2,8 @@ import * as path from "path";
 import * as fs from "fs";
 import * as os from "os";
 import { DocumentUri } from "vscode-languageclient";
+import * as semver from "semver";
+import { getBinaryPathLegacy } from "./utils-legacy";
 
 /*
  * Much of the code in here is duplicated from the server code.
@@ -32,42 +34,110 @@ export function normalizePath(filePath: string | null): NormalizedPath | null {
 
 type binaryName = "rescript-editor-analysis.exe" | "rescript-tools.exe";
 
-const platformDir =
-  process.arch === "arm64" ? process.platform + process.arch : process.platform;
+// v12+ format: with hyphen (e.g., "darwin-arm64")
+const platformTarget = `${process.platform}-${process.arch}`;
 
-const getLegacyBinaryDevPath = (b: binaryName) =>
-  path.join(path.dirname(__dirname), "..", "analysis", b);
+// ============================================================================
+// Version Detection
+// ============================================================================
 
-export const getLegacyBinaryProdPath = (b: binaryName) =>
-  path.join(
-    path.dirname(__dirname),
-    "..",
-    "server",
-    "analysis_binaries",
-    platformDir,
-    b,
+/**
+ * Finds the ReScript version from package.json in the project.
+ */
+export const findReScriptVersion = (
+  projectRootPath: NormalizedPath | null,
+): string | null => {
+  if (projectRootPath == null) {
+    return null;
+  }
+  try {
+    const packageJsonPath = path.join(
+      projectRootPath,
+      "node_modules",
+      "rescript",
+      "package.json",
+    );
+    if (!fs.existsSync(packageJsonPath)) {
+      return null;
+    }
+    const packageJson = JSON.parse(fs.readFileSync(packageJsonPath, "utf-8"));
+    return packageJson.version ?? null;
+  } catch {
+    return null;
+  }
+};
+
+// ============================================================================
+// ReScript 12+ Binary Finding (Clean, self-contained)
+// ============================================================================
+
+/**
+ * Finds binaries for ReScript 12+ using @rescript/${target}/bin.js structure.
+ * This is the single source of truth for binary locations in v12+.
+ * Returns null if binary not found, throws on critical errors.
+ */
+const getBinaryPathReScript12 = (
+  projectRootPath: NormalizedPath,
+  binaryName: binaryName,
+): string | null => {
+  const binJsPath = path.join(
+    projectRootPath,
+    "node_modules",
+    "@rescript",
+    platformTarget,
+    "bin.js",
   );
 
+  if (!fs.existsSync(binJsPath)) {
+    return null;
+  }
+
+  // Read bin.js and extract the binary path
+  // bin.js exports binPaths object with paths to binaries
+  const binDir = path.join(
+    projectRootPath,
+    "node_modules",
+    "@rescript",
+    platformTarget,
+    "bin",
+  );
+
+  let binaryPath: string | null = null;
+  if (binaryName === "rescript-tools.exe") {
+    binaryPath = path.join(binDir, "rescript-tools.exe");
+  } else if (binaryName === "rescript-editor-analysis.exe") {
+    binaryPath = path.join(binDir, "rescript-editor-analysis.exe");
+  }
+
+  if (binaryPath != null && fs.existsSync(binaryPath)) {
+    return binaryPath;
+  }
+  return null;
+};
+
+// ============================================================================
+// Main Binary Finding Function (Routes to v12 or legacy)
+// ============================================================================
+
+/**
+ * Finds a ReScript binary, routing to v12+ or legacy implementation.
+ * Top-level if separates the two code paths completely.
+ */
 export const getBinaryPath = (
   binaryName: "rescript-editor-analysis.exe" | "rescript-tools.exe",
   projectRootPath: NormalizedPath | null = null,
 ): string | null => {
-  const binaryFromCompilerPackage = path.join(
-    projectRootPath ?? "",
-    "node_modules",
-    "rescript",
-    platformDir,
-    binaryName,
-  );
+  const rescriptVersion = findReScriptVersion(projectRootPath);
+  const isReScript12OrHigher =
+    rescriptVersion != null &&
+    semver.valid(rescriptVersion) &&
+    semver.gte(rescriptVersion, "12.0.0");
 
-  if (projectRootPath != null && fs.existsSync(binaryFromCompilerPackage)) {
-    return binaryFromCompilerPackage;
-  } else if (fs.existsSync(getLegacyBinaryDevPath(binaryName))) {
-    return getLegacyBinaryDevPath(binaryName);
-  } else if (fs.existsSync(getLegacyBinaryProdPath(binaryName))) {
-    return getLegacyBinaryProdPath(binaryName);
+  // Top-level separation: v12+ or legacy
+  if (isReScript12OrHigher && projectRootPath != null) {
+    return getBinaryPathReScript12(projectRootPath, binaryName);
   } else {
-    return null;
+    return getBinaryPathLegacy(projectRootPath, binaryName);
   }
 };