Semantic-Org/Semantic-UI · warning

{name} must contain "{ruleValue}"

Error message

{name} must contain "{ruleValue}"

What it means

Default prompt keyed under `contain` in settings.prompt (form.js:1266). IMPORTANT quirk: the rule FUNCTION is named `contains` (form.js:1458) — there is no `settings.rules.contain`. Because `module.get.ruleName` (form.js:395) returns the rule type verbatim, using `{type:'contain[...]'}` yields ruleName `contain`, `settings.rules['contain']` is undefined, and `module.error(error.noRule)` fires (form.js:1024-1026). The intended usage is `{type:'contains[...]'}`, but then the prompt lookup `settings.prompt['contains']` is undefined and falls back to `unspecifiedRule`. So this `contain` message is effectively unreachable unless you set an explicit `rule.prompt`.

Source

Thrown at src/definitions/behaviors/form.js:1266

  text: {
    unspecifiedRule  : 'Please enter a valid value',
    unspecifiedField : 'This field'
  },

  prompt: {
    empty                : '{name} must have a value',
    checked              : '{name} must be checked',
    email                : '{name} must be a valid e-mail',
    url                  : '{name} must be a valid url',
    regExp               : '{name} is not formatted correctly',
    integer              : '{name} must be an integer',
    decimal              : '{name} must be a decimal number',
    number               : '{name} must be set to a number',
    is                   : '{name} must be "{ruleValue}"',
    isExactly            : '{name} must be exactly "{ruleValue}"',
    not                  : '{name} cannot be set to "{ruleValue}"',
    notExactly           : '{name} cannot be set to exactly "{ruleValue}"',
    contain              : '{name} must contain "{ruleValue}"',
    containExactly       : '{name} must contain exactly "{ruleValue}"',
    doesntContain        : '{name} cannot contain  "{ruleValue}"',
    doesntContainExactly : '{name} cannot contain exactly "{ruleValue}"',
    minLength            : '{name} must be at least {ruleValue} characters',
    length               : '{name} must be at least {ruleValue} characters',
    exactLength          : '{name} must be exactly {ruleValue} characters',
    maxLength            : '{name} cannot be longer than {ruleValue} characters',
    match                : '{name} must match {ruleValue} field',
    different            : '{name} must have a different value than {ruleValue} field',
    creditCard           : '{name} must be a valid credit card number',
    minCount             : '{name} must have at least {ruleValue} choices',
    exactCount           : '{name} must have exactly {ruleValue} choices',
    maxCount             : '{name} must have {ruleValue} or less choices'
  },

  selector : {
    checkbox   : 'input[type="checkbox"], input[type="radio"]',
    clear      : '.clear',

View on GitHub (pinned to 597843ab84)

Solutions

1. Use the correct rule type `contains[...]` AND supply an explicit `prompt`, since the default `contain` key is never matched.
2. Add the missing alias globally: `$.fn.form.settings.rules.contain = $.fn.form.settings.rules.contains; $.fn.form.settings.prompt.contains = $.fn.form.settings.prompt.contain;`.
3. If you only need the message, set `rules:[{type:'contains[abc]', prompt:'Must contain "abc"'}]`.

Example fix

// before - prompt key 'contain' never resolves
rules: [{ type: 'contains[abc]' }]  // shows 'Please enter a valid value'

// after - explicit prompt makes the message correct
rules: [{ type: 'contains[abc]', prompt: 'Value must contain "abc"' }]

const needle = 'abc';
if (($field.val() || '').toLowerCase().indexOf(needle.toLowerCase()) === -1) { /* warn */ }

const usesContainsRule = (rule) => /^contains(\[.*\])?$/.test(rule.type || '');

When it happens

Trigger: Intended: `{type:'contains[abc]'}` with input lacking `abc` (case-insensitive substring). Actual: either a `noRule` console error (if you wrote `contain`), or the generic 'Please enter a valid value' fallback (because the prompt key does not match the function name).

Common situations: Developers following docs that mention `contain` and finding the message never appears, or seeing `noRule` errors in the console.

Related errors

• {name} must contain exactly "{ruleValue}"
• {name} cannot contain "{ruleValue}"
• {name} cannot contain exactly "{ruleValue}"
• {name} must be a valid url
• {name} is not formatted correctly

AI-assisted analysis of Semantic-Org/Semantic-UI@597843ab84 (2026-08-13). Data as JSON: /api/errors/f7c29f95fbcb9d16. Report an issue: GitHub.