1 files changed, 180 insertions, 0 deletions
diff --git a/tools/lint/eslint/eslint-plugin-spidermonkey-js/lib/environments/self-hosted.js b/tools/lint/eslint/eslint-plugin-spidermonkey-js/lib/environments/self-hosted.js
new file mode 100644
index 0000000000..37ae42bfa3
--- /dev/null
+++ b/tools/lint/eslint/eslint-plugin-spidermonkey-js/lib/environments/self-hosted.js
@@ -0,0 +1,180 @@
+/**
+ * @fileoverview Add environment defaults to SpiderMonkey's self-hosted JS.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+
+"use strict";
+
+const path = require("path");
+const fs = require("fs");
+
+let gRootDir = null;
+
+// Copied from `tools/lint/eslint/eslint-plugin-mozilla/lib/helpers.js`.
+function getRootDir() {
+  if (!gRootDir) {
+    function searchUpForIgnore(dirName, filename) {
+      let parsed = path.parse(dirName);
+      while (parsed.root !== dirName) {
+        if (fs.existsSync(path.join(dirName, filename))) {
+          return dirName;
+        }
+        // Move up a level
+        dirName = parsed.dir;
+        parsed = path.parse(dirName);
+      }
+      return null;
+    }
+
+    let possibleRoot = searchUpForIgnore(
+      path.dirname(module.filename),
+      ".eslintignore"
+    );
+    if (!possibleRoot) {
+      possibleRoot = searchUpForIgnore(path.resolve(), ".eslintignore");
+    }
+    if (!possibleRoot) {
+      possibleRoot = searchUpForIgnore(path.resolve(), "package.json");
+    }
+    if (!possibleRoot) {
+      // We've couldn't find a root from the module or CWD, so lets just go
+      // for the CWD. We really don't want to throw if possible, as that
+      // tends to give confusing results when used with ESLint.
+      possibleRoot = process.cwd();
+    }
+
+    gRootDir = possibleRoot;
+  }
+
+  return gRootDir;
+}
+
+function tryReadFile(filePath) {
+  let absPath = path.join(getRootDir(), filePath);
+  if (!fs.existsSync(absPath)) {
+    // Safely handle the case when the file wasn't found, because throwing
+    // errors can lead to confusing result when used with ESLint.
+    return "";
+  }
+  return fs.readFileSync(absPath, "utf-8");
+}
+
+// Search for top-level declarations, #defines, and #includes.
+function addGlobalsFrom(dirName, fileName, globals) {
+  let filePath = path.join(dirName, fileName);
+
+  // Definitions are separated by line.
+  let lines = tryReadFile(filePath).split("\n");
+
+  // We don't have to fully parse the source code, because it's formatted
+  // through "prettier", which means we know the exact code structure.
+  //
+  // |class| is disallowed in self-hosted code, so we don't have to handle it.
+  for (let line of lines) {
+    if (
+      line.startsWith("function") ||
+      line.startsWith("function*") ||
+      line.startsWith("async function") ||
+      line.startsWith("async function*")
+    ) {
+      let m = line.match(/^(?:async )?function(?:\*)?\s+([\w\$]+)\s*\(/);
+      if (m) {
+        globals[m[1]] = "readonly";
+      }
+    } else if (
+      line.startsWith("var") ||
+      line.startsWith("let") ||
+      line.startsWith("const")
+    ) {
+      let m = line.match(/^(?:var|let|const)\s+([\w\$]+)\s*[;=]/);
+      if (m) {
+        globals[m[1]] = "readonly";
+      }
+    } else if (line.startsWith("#define")) {
+      let m = line.match(/^#define (\w+)/);
+      if (m) {
+        globals[m[1]] = "readonly";
+      }
+    } else if (line.startsWith("#include")) {
+      let m = line.match(/^#include \"([\w\.]+)\"$/);
+      if (m) {
+        // Also process definitions from includes.
+        addGlobalsFrom(dirName, m[1], globals);
+      }
+    }
+  }
+}
+
+function selfHostingDefines(dirName = "js/src/builtin/") {
+  let absDir = path.join(getRootDir(), dirName);
+  if (!fs.existsSync(absDir)) {
+    // See |tryReadFile| for why we avoid to throw any errors.
+    return {};
+  }
+
+  // Search sub-directories and js-files within |dirName|.
+  let dirs = [];
+  let jsFiles = [];
+  for (let name of fs.readdirSync(absDir)) {
+    let stat = fs.statSync(path.join(absDir, name));
+    if (stat.isDirectory()) {
+      dirs.push(name);
+    } else if (stat.isFile() && name.endsWith(".js")) {
+      jsFiles.push(name);
+    }
+  }
+
+  let globals = Object.create(null);
+
+  // Process each js-file.
+  for (let jsFile of jsFiles) {
+    addGlobalsFrom(dirName, jsFile, globals);
+  }
+
+  // Recursively traverse all sub-directories.
+  for (let dir of dirs) {
+    globals = { ...globals, ...selfHostingDefines(path.join(dirName, dir)) };
+  }
+
+  return globals;
+}
+
+function selfHostingFunctions() {
+  // Definitions can be spread across multiple lines and may have extra
+  // whitespace, so we simply remove all whitespace and match over the complete
+  // file.
+  let content = tryReadFile("js/src/vm/SelfHosting.cpp").replace(/\s+/g, "");
+
+  let globals = Object.create(null);
+  for (let m of content.matchAll(/(?:JS_FN|JS_INLINABLE_FN)\("(\w+)"/g)) {
+    globals[m[1]] = "readonly";
+  }
+  return globals;
+}
+
+function errorNumbers() {
+  // Definitions are separated by line.
+  let lines = tryReadFile("js/public/friend/ErrorNumbers.msg").split("\n");
+
+  let globals = Object.create(null);
+  for (let line of lines) {
+    let m = line.match(/^MSG_DEF\((\w+),/);
+    if (m) {
+      globals[m[1]] = "readonly";
+    }
+  }
+  return globals;
+}
+
+const globals = {
+  ...selfHostingDefines(),
+  ...selfHostingFunctions(),
+  ...errorNumbers(),
+};
+
+module.exports = {
+  globals,
+};