@jridgewell/gen-mapping 0.3.13: allMappings

Clean-room public code sample — generation instructions

Write a brand-new, minimal, self-contained code sample in this clean-room directory.
Do not copy, paraphrase, or reference any existing project source. Work only from this spec.

A csx.json manifest scaffold already exists. Do not recreate it from memory. Preserve its case.goal, packages and symbols; fill its empty case.contract with exact assertions and correct its environment, commands and verifierAdapter for the files you generate.

Goal: verify @jridgewell/gen-mapping.allMappings in pkg:npm/%40jridgewell/gen-mapping@0.3.13
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:npm/%40jridgewell/gen-mapping@0.3.13
Demonstrate these symbols/APIs:
  - @jridgewell/gen-mapping.allMappings

Rules:
  - One focused purpose; the smallest project that proves the goal.
  - Include a contract test (test/contract.*) that runs OFFLINE and exits 0 exactly when the goal behavior works.
  - Pin every dependency with a lockfile so resolution is reproducible.
  - No secrets, credentials, or tokens. No real URLs (only example.com or localhost). No absolute paths.
  - No personal names, emails, company names, or project identifiers of any kind.
  - No binaries and no generated output (node_modules, dist, target, venv, .git, .env).
  - Keep it under 200 files and 256KB packed.

{"case":{"caseId":"case:sha256:1b29284ed6186433b32ff70233414e73da1758d0bfd88432f64d6e4a04dedc8c","constraints":{"executionContext":"node"},"contract":["allMappings returns an empty array when given a freshly initialized GenMapping with no mappings","allMappings returns mapping objects with 1-based generated positions and original source positions added via addMapping","allMappings includes the symbol name when a segment is associated with an identifier name","allMappings converts 0-based generated line indices from addSegment to 1-based generated line numbers","allMappings yields undefined source, original, and name fields for sourceless segments","allMappings preserves order across multiple generated lines and multiple segments within the same line","allMappings correctly reconstructs all mapping objects from an imported source map loaded via fromMap","allMappings skips consecutive duplicate mappings when added via maybeAddMapping"],"goal":"verify @jridgewell/gen-mapping.allMappings in pkg:npm/%40jridgewell/gen-mapping@0.3.13","kind":"HOW","packages":["pkg:npm/%40jridgewell/gen-mapping@0.3.13"],"schemaVersion":1,"symbols":["@jridgewell/gen-mapping.allMappings"]},"contractCommand":["node","test/contract.mjs"],"environment":{"arch":"x64","distro":"ubuntu","ecosystem":"npm","executionContext":"node","language":"javascript","libc":"glibc","libcVersion":"2.39","moduleSystem":"esm","os":"linux","osVersionBucket":"24","packageManager":"npm","packageManagerVersion":"10.9.8","runtime":"node","runtimeVersion":"22.23.2","schemaVersion":1},"license":"MIT-0","packages":["pkg:npm/%40jridgewell/gen-mapping@0.3.13"],"schemaVersion":1,"subject":"pkg:npm/%40jridgewell/gen-mapping@0.3.13","symbols":["@jridgewell/gen-mapping.allMappings"],"verifierAdapter":"node-typescript@1"}

{
  "name": "sample-gen-mapping-all-mappings",
  "version": "1.0.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "sample-gen-mapping-all-mappings",
      "version": "1.0.0",
      "license": "MIT-0",
      "dependencies": {
        "@jridgewell/gen-mapping": "0.3.13"
      }
    },
    "node_modules/@jridgewell/gen-mapping": {
      "version": "0.3.13",
      "resolved": "https://registry.npmjs.org/@jridgewell/gen-mapping/-/gen-mapping-0.3.13.tgz",
      "integrity": "sha512-2kkt/7niJ6MgEPxF0bYdQ6etZaA+fQvDcLKckhy1yIQOzaoKjBBjSj63/aLVjYE3qhRt5dvM+uUyfCg6UKCBbA==",
      "license": "MIT",
      "dependencies": {
        "@jridgewell/sourcemap-codec": "^1.5.0",
        "@jridgewell/trace-mapping": "^0.3.24"
      }
    },
    "node_modules/@jridgewell/resolve-uri": {
      "version": "3.1.2",
      "resolved": "https://registry.npmjs.org/@jridgewell/resolve-uri/-/resolve-uri-3.1.2.tgz",
      "integrity": "sha512-bRISgCIjP20/tbWSPWMEi54QVPRZExkuD9lJL+UIxUKtwVJA8wW1Trb1jMs1RFXo1CBTNZ/5hpC9QvmKWdopKw==",
      "license": "MIT",
      "engines": {
        "node": ">=6.0.0"
      }
    },
    "node_modules/@jridgewell/sourcemap-codec": {
      "version": "1.5.5",
      "resolved": "https://registry.npmjs.org/@jridgewell/sourcemap-codec/-/sourcemap-codec-1.5.5.tgz",
      "integrity": "sha512-cYQ9310grqxueWbl+WuIUIaiUaDcj7WOq5fVhEljNVgRfOUhY9fy2zTvfoqWsnebh8Sl70VScFbICvJnLKB0Og==",
      "license": "MIT"
    },
    "node_modules/@jridgewell/trace-mapping": {
      "version": "0.3.31",
      "resolved": "https://registry.npmjs.org/@jridgewell/trace-mapping/-/trace-mapping-0.3.31.tgz",
      "integrity": "sha512-zzNR+SdQSDJzc8joaeP8QQoCQr8NuYx2dIIytl1QeBEZHJ9uW6hebsrYgbz8hJwUQao3TWCMtmfV8Nu1twOLAw==",
      "license": "MIT",
      "dependencies": {
        "@jridgewell/resolve-uri": "^3.1.0",
        "@jridgewell/sourcemap-codec": "^1.4.14"
      }
    }
  }
}

{
  "name": "sample-gen-mapping-all-mappings",
  "version": "1.0.0",
  "type": "module",
  "private": true,
  "license": "MIT-0",
  "scripts": {
    "test": "node test/contract.mjs"
  },
  "dependencies": {
    "@jridgewell/gen-mapping": "0.3.13"
  }
}

{
  "schemaVersion": 1,
  "goal": "verify @jridgewell/gen-mapping.allMappings in pkg:npm/%40jridgewell/gen-mapping@0.3.13",
  "kind": "HOW",
  "packages": [
    "pkg:npm/%40jridgewell/gen-mapping@0.3.13"
  ],
  "symbols": [
    "@jridgewell/gen-mapping.allMappings"
  ]
}

import { allMappings } from '@jridgewell/gen-mapping';

/**
 * Extracts all mapping records from a GenMapping instance.
 * @param {import('@jridgewell/gen-mapping').GenMapping} map
 * @returns {import('@jridgewell/gen-mapping').Mapping[]}
 */
export function extractMappings(map) {
  return allMappings(map);
}

export { allMappings };

import assert from 'node:assert/strict';
import {
  GenMapping,
  addMapping,
  addSegment,
  maybeAddMapping,
  allMappings,
  fromMap,
  toEncodedMap,
} from '@jridgewell/gen-mapping';
import { extractMappings } from '../src/index.mjs';

// 1. allMappings returns an empty array when given a freshly initialized GenMapping with no mappings
{
  const map = new GenMapping();
  const mappings = allMappings(map);
  assert.ok(Array.isArray(mappings));
  assert.equal(mappings.length, 0);

  const helperMappings = extractMappings(map);
  assert.deepEqual(helperMappings, []);
}

// 2. allMappings returns mapping objects with 1-based generated positions and original source positions added via addMapping
{
  const map = new GenMapping();
  addMapping(map, {
    generated: { line: 1, column: 0 },
    source: 'main.js',
    original: { line: 10, column: 2 },
  });
  const mappings = allMappings(map);
  assert.equal(mappings.length, 1);
  assert.deepEqual(mappings[0], {
    generated: { line: 1, column: 0 },
    source: 'main.js',
    original: { line: 10, column: 2 },
    name: undefined,
  });
}

// 3. allMappings includes the symbol name when a segment is associated with an identifier name
{
  const map = new GenMapping();
  addMapping(map, {
    generated: { line: 1, column: 5 },
    source: 'util.js',
    original: { line: 3, column: 8 },
    name: 'calculateTotal',
  });
  const mappings = allMappings(map);
  assert.equal(mappings.length, 1);
  assert.deepEqual(mappings[0], {
    generated: { line: 1, column: 5 },
    source: 'util.js',
    original: { line: 3, column: 8 },
    name: 'calculateTotal',
  });
}

// 4. allMappings converts 0-based generated line indices from addSegment to 1-based generated line numbers
{
  const map = new GenMapping();
  addSegment(map, 0, 4, 'mod.js', 5, 12);
  addSegment(map, 2, 8, 'mod.js', 7, 0);
  const mappings = allMappings(map);
  assert.equal(mappings.length, 2);
  assert.deepEqual(mappings[0], {
    generated: { line: 1, column: 4 },
    source: 'mod.js',
    original: { line: 6, column: 12 },
    name: undefined,
  });
  assert.deepEqual(mappings[1], {
    generated: { line: 3, column: 8 },
    source: 'mod.js',
    original: { line: 8, column: 0 },
    name: undefined,
  });
}

// 5. allMappings yields undefined source, original, and name fields for sourceless segments
{
  const map = new GenMapping();
  addSegment(map, 0, 0);
  addSegment(map, 0, 10, 'app.js', 0, 0);
  const mappings = allMappings(map);
  assert.equal(mappings.length, 2);
  assert.deepEqual(mappings[0], {
    generated: { line: 1, column: 0 },
    source: undefined,
    original: undefined,
    name: undefined,
  });
  assert.deepEqual(mappings[1], {
    generated: { line: 1, column: 10 },
    source: 'app.js',
    original: { line: 1, column: 0 },
    name: undefined,
  });
}

// 6. allMappings preserves order across multiple generated lines and multiple segments within the same line
{
  const map = new GenMapping();
  addMapping(map, { generated: { line: 1, column: 0 }, source: 'a.js', original: { line: 1, column: 0 } });
  addMapping(map, { generated: { line: 1, column: 15 }, source: 'a.js', original: { line: 1, column: 8 }, name: 'foo' });
  addMapping(map, { generated: { line: 2, column: 4 }, source: 'b.js', original: { line: 5, column: 0 } });
  const mappings = allMappings(map);
  assert.equal(mappings.length, 3);
  assert.equal(mappings[0].generated.line, 1);
  assert.equal(mappings[0].generated.column, 0);
  assert.equal(mappings[1].generated.line, 1);
  assert.equal(mappings[1].generated.column, 15);
  assert.equal(mappings[1].name, 'foo');
  assert.equal(mappings[2].generated.line, 2);
  assert.equal(mappings[2].generated.column, 4);
}

// 7. allMappings correctly reconstructs all mapping objects from an imported source map loaded via fromMap
{
  const original = new GenMapping({ file: 'bundle.js' });
  addMapping(original, { generated: { line: 1, column: 0 }, source: 'src.js', original: { line: 1, column: 0 } });
  addMapping(original, { generated: { line: 2, column: 5 }, source: 'src.js', original: { line: 2, column: 10 }, name: 'bar' });
  const encoded = toEncodedMap(original);

  const imported = fromMap(encoded);
  const mappings = allMappings(imported);
  assert.deepEqual(mappings, allMappings(original));
}

// 8. allMappings skips consecutive duplicate mappings when added via maybeAddMapping
{
  const map = new GenMapping();
  maybeAddMapping(map, { generated: { line: 1, column: 0 }, source: 'src.js', original: { line: 1, column: 0 } });
  maybeAddMapping(map, { generated: { line: 1, column: 4 }, source: 'src.js', original: { line: 1, column: 0 } });
  const mappings = allMappings(map);
  assert.equal(mappings.length, 1);
  assert.deepEqual(mappings[0], {
    generated: { line: 1, column: 0 },
    source: 'src.js',
    original: { line: 1, column: 0 },
    name: undefined,
  });
}

console.log('Contract tests passed successfully.');