Fix read subtree bug for sub directories

Author: jahooma

packages/agent-runtime/src/tools/handlers/__tests__/read-subtree.test.ts

@@ -140,6 +140,64 @@ describe('handleReadSubtree', () => {
     expect(String(errEntry.errorMessage)).toContain('Path not found or ignored')
   })
 
+  it('includes variables when reading a subdirectory with proper path mapping', async () => {
+    const fileContext = buildMockFileContext()
+    const logger = createLogger()
+
+    // Test with a deeper nested structure to expose potential path issues
+    fileContext.fileTree = [
+      {
+        name: 'packages',
+        type: 'directory',
+        filePath: 'packages',
+        children: [
+          {
+            name: 'backend',
+            type: 'directory',
+            filePath: 'packages/backend',
+            children: [
+              {
+                name: 'index.ts',
+                type: 'file',
+                filePath: 'packages/backend/index.ts',
+                lastReadTime: 0,
+              },
+            ],
+          },
+        ],
+      },
+    ]
+    fileContext.fileTokenScores = {
+      'packages/backend/index.ts': { myFunction: 5.0, myClass: 3.0 },
+    }
+
+    const toolCall: CodebuffToolCall<'read_subtree'> = {
+      toolName: 'read_subtree',
+      toolCallId: 'tc-subdir',
+      input: { paths: ['packages/backend'], maxTokens: 50000 },
+    }
+
+    const { result } = handleReadSubtree({
+      previousToolCallFinished: Promise.resolve(),
+      toolCall,
+      fileContext,
+      logger,
+    })
+
+    const output = await result
+    expect(output[0].type).toBe('json')
+    const value = output[0].value as any[]
+    const dirEntry = value.find(
+      (v) => v.type === 'directory' && v.path === 'packages/backend',
+    )
+    expect(dirEntry).toBeTruthy()
+    expect(typeof dirEntry.printedTree).toBe('string')
+
+    // The printedTree should include the variable names from fileTokenScores
+    expect(dirEntry.printedTree).toContain('myFunction')
+    expect(dirEntry.printedTree).toContain('myClass')
+  })
+
   it('honors maxTokens by reducing token count under a tiny budget', async () => {
     const fileContext = buildMockFileContext()
     const logger = createLogger()

packages/agent-runtime/src/tools/handlers/tool/read-subtree.ts

@@ -14,7 +14,6 @@ import type {
 
 type ToolName = 'read_subtree'
 
-
 export const handleReadSubtree = ((params: {
   previousToolCallFinished: Promise<void>
   toolCall: CodebuffToolCall<ToolName>
@@ -31,9 +30,44 @@ export const handleReadSubtree = ((params: {
   const allFiles = new Set(getAllFilePaths(fileContext.fileTree))
 
   const buildDirectoryResult = (dirNodes: FileTreeNode[], outPath: string) => {
+    const subTree = deepClone(dirNodes)
+
+    // Remap token scores so keys match the paths built by printFileTreeWithTokens.
+    // When printFileTreeWithTokens walks a subtree starting from dirNodes,
+    // it builds paths starting from the node names, not from an empty root.
+    // So for a node with name 'backend' inside 'packages', the paths will be
+    // 'backend/file.ts', not 'packages/backend/file.ts'.
+    const remappedTokenScores: Record<string, Record<string, number>> = {}
+    const prefix =
+      outPath === '.' || outPath === '/' || outPath === ''
+        ? ''
+        : outPath.replace(/\\/g, '/')
+
+    for (const [filePath, tokens] of Object.entries(
+      fileContext.fileTokenScores,
+    )) {
+      const normalized = filePath.replace(/\\/g, '/')
+      if (!prefix || normalized.startsWith(prefix + '/')) {
+        // Strip the parent path prefix and keep the dirBaseName + remainder
+        const fullPrefix = prefix
+          ? prefix.split('/').slice(0, -1).join('/')
+          : ''
+        const afterParent = fullPrefix
+          ? normalized.startsWith(fullPrefix + '/')
+            ? normalized.slice(fullPrefix.length + 1)
+            : null
+          : normalized
+
+        if (afterParent && !afterParent.startsWith('../')) {
+          remappedTokenScores[afterParent] = tokens
+        }
+      }
+    }
+
     const subctx: ProjectFileContext = {
       ...fileContext,
-      fileTree: deepClone(dirNodes),
+      fileTree: subTree,
+      fileTokenScores: remappedTokenScores,
     }
     const { printedTree, tokenCount, truncationLevel } =
       truncateFileTreeBasedOnTokenBudget({