Fix React var and AGENTS.md patching 2.1.62 (#563)

Author: bl-ue

CHANGELOG.md

@@ -7,6 +7,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## Unreleased
 
+- Fix React var and AGENTS.md patching 2.1.62 (#563) - @bl-ue
+
 ## [v4.0.9](https://github.com/Piebald-AI/tweakcc/releases/tag/v4.0.9) - 2026-02-25
 
 - Add Nix support (#548) - @signadou

README.md

@@ -161,7 +161,7 @@ $ pnpm dlx tweakcc
 
 tweakcc works by patching Claude Code's minified `cli.js` file, reading customizations from `~/.tweakcc/config.json`. For npm-based installations `cli.js` is modified directly, but for native installations it's extracted from the binary using [node-lief](https://github.com/Piebald-AI/node-lief), patched, and then the binary is repacked. When you update your Claude Code installation, your customizations will be overwritten, but they're remembered in your configuration file, so they can be reapplied by just running `npx tweakcc --apply`.
 
-tweakcc is verified to work with Claude Code **2.1.55.** In newer or earlier versions various patches might not work. However, if we have the [system prompts for your version](https://github.com/Piebald-AI/tweakcc/tree/main/data/prompts) then system prompt patching is guaranteed to work with that version, even if it's significantly different from the verified CC version—the version number stated above is only relevant for the non-system-prompt patches. We get the latest system prompts within minutes of each new CC release, so unless you're using a CC version older than 2.0.14, your version is supported.
+tweakcc is verified to work with Claude Code **2.1.62.** In newer or earlier versions various patches might not work. However, if we have the [system prompts for your version](https://github.com/Piebald-AI/tweakcc/tree/main/data/prompts) then system prompt patching is guaranteed to work with that version, even if it's significantly different from the verified CC version—the version number stated above is only relevant for the non-system-prompt patches. We get the latest system prompts within minutes of each new CC release, so unless you're using a CC version older than 2.0.14, your version is supported.
 
 You can also create custom patches using tweakcc without having to fork it or open a PR. [`tweakcc adhoc-patch`](#cli-commands) supports using custom scripts that work with native and npm-based installs and that automatically detect your Claude Code installation.
 

src/patches/agentsMd.ts

@@ -7,82 +7,30 @@ import { showDiff } from './index';
  * filenames (e.g., AGENTS.md).
  *
  * This finds the function that reads CLAUDE.md files and modifies it to:
- * 1. First try the original CLAUDE.md path
- * 2. If not found, try each alternative name in order
+ * 1. Add a `didReroute` parameter to the function
+ * 2. Right before the `return {` statement, check if the path ends with
+ *    CLAUDE.md and try alternative names (unless didReroute is true)
+ * 3. Recursive calls pass didReroute=true to avoid infinite loops
  *
- * CC 1.0.24:
+ * CC 2.1.62 (approx. by Claude):
  * ```diff
- *  function gE2(A, B) {
- *    try {
- *      if (f1().existsSync(A)) {
- *        if (!f1().statSync(A).isFile()) return null;
- *        let I = f1().readFileSync(A, { encoding: "utf-8" });
- *        return { path: A, type: B, content: I };
- * +    } else if (A.endsWith("/CLAUDE.md") || A.endsWith("\\CLAUDE.md")) {
- * +      for (let alt of ["AGENTS.md", "GEMINI.md", "QWEN.md"]) {
- * +        let altPath = A.slice(0, -9) + alt;
- * +        if (f1().existsSync(altPath) && f1().statSync(altPath).isFile())
- * +          return gE2(altPath, B);
- * +      }
- * +    }
- *    } catch (Q) {
- *      if (Q instanceof Error && Q.message.includes("EACCES"))
- *        N1("tengu_claude_md_permission_error", {
- *          is_access_error: 1,
- *          has_home_dir: A.includes(z4()) ? 1 : 0,
- *        });
- *    }
- *    return null;
- *  }
- * ```
- *
- * CC 2.0.0:
- * ```
- *  function q8B(A, B) {
- *    try {
- *      if (C1().existsSync(A)) {
- *        if (!C1().statSync(A).isFile()) return null;
- *        let Z = C1().readFileSync(A, { encoding: "utf-8" });
- *        return { path: A, type: B, content: Z };
- * +    } else if (A.endsWith("/CLAUDE.md") || A.endsWith("\\CLAUDE.md")) {
- * +      for (let alt of ["AGENTS.md", "GEMINI.md", "QWEN.md"]) {
- * +        let altPath = A.slice(0, -9) + alt;
- * +        if (C1().existsSync(altPath) && C1().statSync(altPath).isFile())
- * +          return q8B(altPath, B);
- * +      }
- *      }
- *    } catch (Q) {
- *      if (Q instanceof Error && Q.message.includes("EACCES"))
- *        B1("tengu_claude_md_permission_error", {
- *          is_access_error: 1,
- *          has_home_dir: A.includes(p2()) ? 1 : 0,
- *        });
- *    }
- *    return null;
- *  }
- * ```
- *
- * CC 2.1.29:
- * ```
- *  function _t7(A, q) {
+ * -function _t7(A, q) {
+ * +function _t7(A, q, didReroute) {
  *    try {
  *      let K = x1();
- * -    if (!K.existsSync(A) || !K.statSync(A).isFile()) return null;
- * +    if (!K.existsSync(A) || !K.statSync(A).isFile()) {
- * +      if (A.endsWith("/CLAUDE.md") || A.endsWith("\\CLAUDE.md")) {
- * +        for (let alt of ["AGENTS.md", "GEMINI.md", "QWEN.md"]) {
- * +          let altPath = A.slice(0, -9) + alt;
- * +          if (K.existsSync(altPath) && K.statSync(altPath).isFile())
- * +            return _t7(altPath, q);
- * +        }
- * +      }
- * +      return null;
- * +    }
+ *      if (!K.existsSync(A) || !K.statSync(A).isFile()) return null;
  *      let Y = UL9(A).toLowerCase();
  *      if (Y && !dL9.has(Y))
  *        return (I(`Skipping non-text file in @include: ${A}`), null);
  *      let z = K.readFileSync(A, { encoding: "utf-8" }),
  *        { content: w, paths: H } = cL9(z);
+ * +    if (!didReroute && (A.endsWith("/CLAUDE.md") || A.endsWith("\\CLAUDE.md"))) {
+ * +      for (let alt of ["AGENTS.md", "GEMINI.md", "QWEN.md"]) {
+ * +        let altPath = A.slice(0, -9) + alt;
+ * +        if (K.existsSync(altPath) && K.statSync(altPath).isFile())
+ * +          return _t7(altPath, q, true);
+ * +      }
+ * +    }
  *      return { path: A, type: q, content: w, globs: H };
  *    } catch (K) {
  *      if (K instanceof Error && K.message.includes("EACCES"))
@@ -99,85 +47,57 @@ export const writeAgentsMd = (
   file: string,
   altNames: string[]
 ): string | null => {
-  // Step 1: Find the function that handles CLAUDE.md file reading
-  // Pattern: function xyz(a, b) { ...... return { ... path: ..., content: ... } }
   const funcPattern =
-    /function ([$\w]+)\(([$\w]+),([$\w]+)\)(?:.|\n){0,500}Skipping non-text file in @include(?:.|\n){0,500}\{path:[$\w]+,.{0,20}?content:[$\w]+/;
+    /(function ([$\w]+)\(([$\w]+),([^)]+?))\)(?:.|\n){0,500}Skipping non-text file in @include(?:.|\n){0,500}return\{path:[$\w]+,.{0,20}?content:[$\w]+/;
 
   const funcMatch = file.match(funcPattern);
-
   if (!funcMatch || funcMatch.index === undefined) {
     console.error('patch: agentsMd: failed to find CLAUDE.md reading function');
     return null;
   }
-
-  const functionName = funcMatch[1];
-  const firstParam = funcMatch[2];
-  const secondParam = funcMatch[3];
+  const upToFuncParamsClosingParen = funcMatch[1];
+  const functionName = funcMatch[2];
+  const firstParam = funcMatch[3];
+  const restParams = funcMatch[4];
   const funcStart = funcMatch.index;
 
-  // Step 2: Find the fs expression used in the function
-  // Search within the matched region for fsVar.readFileSync etc. or fsVar().readFileSync etc.
   const fsPattern = /([$\w]+(?:\(\))?)\.(?:readFileSync|existsSync|statSync)/;
   const fsMatch = funcMatch[0].match(fsPattern);
-
   if (!fsMatch) {
     console.error('patch: agentsMd: failed to find fs expression in function');
     return null;
   }
-
   const fsExpr = fsMatch[1];
 
-  // Prepare the alternative names as JSON
   const altNamesJson = JSON.stringify(altNames);
 
-  // Build the injection code
-  const buildInjection = () =>
-    `if(${firstParam}.endsWith("/CLAUDE.md")||${firstParam}.endsWith("\\\\CLAUDE.md")){for(let alt of ${altNamesJson}){let altPath=${firstParam}.slice(0,-9)+alt;if(${fsExpr}.existsSync(altPath)&&${fsExpr}.statSync(altPath).isFile())return ${functionName}(altPath,${secondParam});}}return null;`;
-
-  // Step 3: Try the primary pattern (CC 2.1.29)
-  // Pattern: if(!fs.existsSync(path)||!fs.statSync(path).isFile())return null;
-  const primaryPattern =
-    /(if\(![$\w]+\.existsSync\([$\w]+\)\|\|![$\w]+\.statSync\([$\w]+\)\.isFile\(\)\))return null;/;
-  const primaryMatch = file.slice(funcStart).match(primaryPattern);
-
-  if (primaryMatch && primaryMatch.index !== undefined) {
-    const injection = buildInjection();
-    const replacement = primaryMatch[1] + '{' + injection + '}';
+  const sigIndex = funcStart + upToFuncParamsClosingParen.length;
+  let newFile = file.slice(0, sigIndex) + ',didReroute' + file.slice(sigIndex);
 
-    const startIndex = funcStart + primaryMatch.index;
-    const endIndex = startIndex + primaryMatch[0].length;
+  showDiff(file, newFile, ',didReroute', sigIndex, sigIndex);
 
-    const newFile =
-      file.slice(0, startIndex) + replacement + file.slice(endIndex);
+  // Step 2: Inject rerouting code right before the `return {`
+  const returnPattern = /return\{path:[$\w]+,.{0,20}?content:[$\w]+/;
+  const returnMatch = newFile.slice(funcStart).match(returnPattern);
 
-    showDiff(file, newFile, replacement, startIndex, endIndex);
-
-    return newFile;
+  if (!returnMatch || returnMatch.index === undefined) {
+    console.error(
+      'patch: agentsMd: failed to find return statement for injection'
+    );
+    return null;
   }
 
-  // Step 4: Try the fallback pattern (uses }catch or }}catch)
-  // Pattern: }catch or }}catch
-  const fallbackPattern = /(\})(}catch)/;
-  const fallbackMatch = file.slice(funcStart).match(fallbackPattern);
-
-  if (fallbackMatch && fallbackMatch.index !== undefined) {
-    const injection = `else if(${firstParam}.endsWith("/CLAUDE.md")||${firstParam}.endsWith("\\\\CLAUDE.md")){for(let alt of ${altNamesJson}){let altPath=${firstParam}.slice(0,-9)+alt;if(${fsExpr}.existsSync(altPath)&&${fsExpr}.statSync(altPath).isFile())return ${functionName}(altPath,${secondParam});}}`;
-    const replacement = fallbackMatch[1] + injection + fallbackMatch[2];
+  const injection = `if(!didReroute&&(${firstParam}.endsWith("/CLAUDE.md")||${firstParam}.endsWith("\\\\CLAUDE.md"))){for(let alt of ${altNamesJson}){let altPath=${firstParam}.slice(0,-9)+alt;if(${fsExpr}.existsSync(altPath)&&${fsExpr}.statSync(altPath).isFile())return ${functionName}(altPath,${restParams},true);}}`;
 
-    const startIndex = funcStart + fallbackMatch.index;
-    const endIndex = startIndex + fallbackMatch[0].length;
+  const returnStart = funcStart + returnMatch.index;
+  const replacement = injection + returnMatch[0];
 
-    const newFile =
-      file.slice(0, startIndex) + replacement + file.slice(endIndex);
+  newFile =
+    newFile.slice(0, returnStart) +
+    replacement +
+    newFile.slice(returnStart + returnMatch[0].length);
 
-    showDiff(file, newFile, replacement, startIndex, endIndex);
-
-    return newFile;
-  }
+  showDiff(file, newFile, replacement, returnStart, returnStart);
 
-  console.error(
-    'patch: agentsMd: failed to find insertion point in function body'
-  );
-  return null;
+  return newFile;
 };

src/patches/helpers.ts

@@ -41,11 +41,19 @@ export const getModuleLoaderFunction = (
   }
 
   // NPM bundles: var T=(H,$,A)=>{ at the start
-  const firstChunk = fileContents.slice(0, 1000);
-  const pattern = /(?:var |,)([$\w]+)=\([$\w]+,[$\w]+,[$\w]+\)=>\{/;
-  const match = firstChunk.match(pattern);
-  if (match) {
-    return match[1];
+  // In newer versions there are more than one, and the one with the shortest name
+  // is the most common one and therefore the correct one.
+  const firstChunk = fileContents.slice(0, 10000);
+  const pattern = /(?:var |,)([$\w]+)=\([$\w]+,[$\w]+,[$\w]+\)=>\{/g;
+  const matches = Array.from(firstChunk.matchAll(pattern));
+  if (matches.length > 0) {
+    let shortest = matches[0][1];
+    for (const m of matches) {
+      if (m[1].length < shortest.length) {
+        shortest = m[1];
+      }
+    }
+    return shortest;
   }
 
   console.log(