usebruno/bruno · error · Error

Creating a env variable without specifying a name is not all

Error message

Creating a env variable without specifying a name is not allowed.

What it means

Thrown by bru.setEnvVar(key, value) when the key argument is falsy (undefined, null, empty string, 0, false). The guard at bru.js:199 checks !key and rejects any falsy value before proceeding to validate the key format and set the variable in the environment scope.

Source

Thrown at packages/bruno-js/src/bru.js:200

  getEnvName() {
    return this.envVariables.__name__;
  }

  getProcessEnv(key) {
    return this.processEnvVars[key];
  }

  hasEnvVar(key) {
    return Object.hasOwn(this.envVariables, key);
  }

  getEnvVar(key) {
    return this.interpolate(this.envVariables[key]);
  }

  setEnvVar(key, value) {
    if (!key) {
      throw new Error('Creating a env variable without specifying a name is not allowed.');
    }

    if (variableNameRegex.test(key) === false) {
      throw new Error(
        `Variable name: "${key}" contains invalid characters! Names must only contain alpha-numeric characters, "-", "_", "."`
      );
    }

    // Deep-equal compare so object/array writes that mutate in place
    // (e.g. `const c = bru.getEnvVar('cfg'); c.port = 4000; bru.setEnvVar('cfg', c);`)
    // still flip the dirty flag — strict `!==` returned false for same-reference writes.
    if (!Object.hasOwn(this.envVariables, key) || !isEqual(this.envVariables[key], value)) {
      this.envVariables[key] = value;
      this._envDirty = true;
    }
  }

  deleteEnvVar(key) {

View on GitHub (pinned to 9bdd81c7bd)

Solutions

Provide a non-empty, static string literal as the key: bru.setEnvVar('token', value).
Validate the key is a non-empty string before calling setEnvVar.
Use a fallback if the key source may be empty: bru.setEnvVar(key || 'default', value).

Example fix

// before
const key = res.getBody()?.name; // may be undefined
bru.setEnvVar(key, 'active');

// after
const key = res.getBody()?.name;
if (key) {
  bru.setEnvVar(key, 'active');
}

Defensive patterns

Strategy: validation

Validate before calling

function isValidEnvVarKey(key) {
  return typeof key === 'string' && key.length > 0;
}
// before calling: if (isValidEnvVarKey(key)) bru.setEnvVar(key, value);

Try / catch

try {
  bru.setEnvVar(key, value);
} catch (e) {
  if (e.message.includes('without specifying a name')) {
    console.error('Environment variable key was empty or missing');
  }
}

Prevention

Always pass a non-empty string literal as the key argument.
Guard dynamic keys with a truthiness check.
Use a fallback key when the source may be empty.

When it happens

Trigger: Calling bru.setEnvVar(undefined, 'value'), bru.setEnvVar('', 'value'), bru.setEnvVar(null, 'value'), or passing a variable name computed dynamically that evaluates to empty (e.g., bru.setEnvVar(req.getUrl(), 'value') when the URL is empty).

Common situations: Using a dynamically computed key from request data that may be empty (e.g., extracting a header that is not present). Forgetting to pass the key argument. Using a variable that has not been initialized as the key.

Related errors

AI-assisted analysis of usebruno/bruno@9bdd81c7bd (2026-08-13). Data as JSON: /api/errors/a60d1df8b8ace542. Report an issue: GitHub.