Grader: file-contains

Taxonomy

Property	Value
Determinism	static
Cost	low
Reference	reference-free
Temporal scope	trajectory-level
Score kind	code

Config

graders:
  - type: file-contains
    config:
      path: "add.test.js"
      value: "expect"

Field	Type	Required	Description
path	string	Yes	File path (or glob) to check
value	string	Yes	Text that must appear in the file
negate	boolean	No	When true, passes when the value is NOT found

Negated variant

Use file-not-contains as a shorthand for negate: true:

graders:
  - type: file-not-contains
    config:
      path: "*.csproj"
      value: "packages.config"

This is equivalent to type: file-contains with negate: true.

Behavior

1. Finds files matching path in the workspace using glob
2. Reads each matching file as UTF-8
3. Checks if the file contains value (case-sensitive)

Glob patterns match regular files, including dotfiles and files inside dot-directories. Directories, symlinks, and other special entries are not matched.

Passes when the value is found in at least one readable matching file. In negated mode, it passes only when every matching file is readable and none contains the value, or when no files match. Fails otherwise. If unreadable matching files prevent a conclusive result, both normal and negated modes fail.

Unreadable files

If a matching file can’t be read (for example, because access is denied or it was removed after matching), it is skipped and noted in the evidence string. If a later readable file matches, the evidence includes the earlier skipped files. If no readable file contains the value but any candidate was unreadable, the result is indeterminate: both normal and negated modes fail because presence or absence cannot be proven. In that case, the evidence lists the unreadable files and states what could not be proven. Binary files are NOT skipped — readFile("utf-8") returns mojibake for binary content, which simply won’t match most substrings.

Evidence examples

✔ 'expect' found in add.test.js
✘ 'expect' NOT found in add.test.js
✘ No files matching 'add.test.js' found
✔ 'expect' found in add.test.js (skipped 1 unreadable file: obj/Debug/app.dll)
✘ Indeterminate: 'expect' not found in any readable file matching '*.txt'; 1 unreadable file: skip.txt. Cannot prove absence.