@glion/lint-profile-field-repetition

Lint rule that flags non-repeatable fields with multiple repetitions.

What it does

Flags fields that contain more than one repetition (delimited by ~) when the HL7v2 profile for the message's version declares repeatable: false for that field. The rule reads profile context attached by @glion/annotate-profile-context. A single repetition is always valid regardless of the repeatable flag; only 2+ repetitions on a non-repeatable field are reported. Segments without a known profile are silently skipped.

Install

npm install @glion/lint-profile-field-repetition

Use

import { hl7v2AnnotateProfileContext } from "@glion/annotate-profile-context";
import { hl7v2Parser } from "@glion/parser";
import hl7v2LintFieldRepetition from "@glion/lint-profile-field-repetition";
import { unified } from "unified";
import { reporter } from "vfile-reporter";

const message = [
  "MSH|^~\\&|SENDER|FAC|RECV|RFAC|20250601120000||ADT^A01^ADT_A01|MSG00001|P|2.5",
  "PID|1||PATID1234^^^HOSP^MR||DOE^JANE||19800101|F",
].join("\r");

const file = await unified()
  .use(hl7v2Parser)
  .use(hl7v2AnnotateProfileContext)
  .use(hl7v2LintFieldRepetition)
  .process(message);

console.error(reporter([file]));

API

unified().use(hl7v2LintFieldRepetition)

A unified lint rule plugin. Takes no options.

Reads file.data.profile. For each field under a segment with a known profile it looks up the field entry by sequence. If the field's profile sets repeatable: false and the AST has more than one repetition, the rule emits one message for that field.

import type { Plugin } from "unified";
import type { Root } from "@glion/ast";

declare const hl7v2LintFieldRepetition: Plugin<[], Root>;
export default hl7v2LintFieldRepetition;

What it checks

This rule flags fields with multiple ~-delimited repetitions when the profile marks the field as non-repeatable. For example, PID-7 (Date of Birth) is not repeatable in v2.5.

Valid

PID-7 carries a single Date of Birth:

MSH|^~\&|SENDER|FAC|RECV|RFAC|20250601120000||ADT^A01^ADT_A01|MSG00001|P|2.5
PID|1||PATID1234^^^HOSP^MR||DOE^JANE||19800101|F

Invalid

PID-7 carries two ~-separated values, which violates the v2.5 profile for the PID-7 field:

MSH|^~\&|SENDER|FAC|RECV|RFAC|20250601120000||ADT^A01^ADT_A01|MSG00001|P|2.5
PID|1||PATID1234^^^HOSP^MR||DOE^JANE||19800101~19800102|F

Reported message:

Field PID-7 (Date/Time of Birth) is not repeatable but has 2 repetitions

When the field name is available in the profile it appears in parentheses after the position. The reported count equals the number of repetitions present in the field.

Part of Glion

@glion/lint-profile-field-repetition is part of Glion, the application framework for HL7v2. See the Glion README for the full package catalog and architecture.