From 8626fa4c099e79ca9d8fec7e1297ddd51e79dfba Mon Sep 17 00:00:00 2001
From: Roy Gal <roy.gal@pentera.io>
Date: Mon, 3 Aug 2026 12:05:44 +0300
Subject: [PATCH] fix: add "type": "module" + rename CJS bundle to .cjs (fixes
 #233)
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Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

@dagrejs/graphlib points exports.import at dist/graphlib.esm.js (ESM syntax)
but has no "type": "module", so runtimes that don't auto-detect ESM (tsx,
Node without --experimental-detect-module) treat that .js file as CommonJS.
Named imports then resolve to undefined and `new Graph()` throws TypeError.

Add "type": "module" so the ESM bundle is interpreted as ESM, and rename the
CJS bundle from dist/graphlib.cjs.js to dist/graphlib.cjs — the .cjs extension
is pinned to CommonJS regardless of package type, so `require()` keeps working.
A naive "Option A" (type: module without the .cjs rename) would break
require() with ERR_REQUIRE_ESM, since the CJS bundle is a .js file using
module.exports.

The IIFE browser bundles (dist/graphlib.js, dist/graphlib.min.js) stay .js:
they are loaded via <script>, are not in the Node exports map, and are
unaffected by "type": "module".

Adds test/dist-exports.test.ts, which exercises the BUILT dist via real
runtimes (tsx for ESM, node for CJS) by importing it at an absolute path —
test/bundle-test.ts imports source via ts-jest and cannot catch a dist-format
bug. The ESM case fails on the current code (only `default` is exported) and
passes after this change; the CJS case stays green throughout.

Closes #233.

Co-Authored-By: Claude <noreply@anthropic.com>
---
 Makefile                                      |  2 +-
 build.ts                                      |  2 +-
 dist/{graphlib.cjs.js => graphlib.cjs}        |  2 +-
 .../{graphlib.cjs.js.map => graphlib.cjs.map} |  0
 package.json                                  |  5 +-
 test/dist-exports.test.ts                     | 92 +++++++++++++++++++
 6 files changed, 98 insertions(+), 5 deletions(-)
 rename dist/{graphlib.cjs.js => graphlib.cjs} (99%)
 rename dist/{graphlib.cjs.js.map => graphlib.cjs.map} (100%)
 create mode 100644 test/dist-exports.test.ts

diff --git a/Makefile b/Makefile
index 3a35a4de..19f1f4ab 100644
--- a/Makefile
+++ b/Makefile
@@ -6,7 +6,7 @@ DIST_DIR = dist
 
 SRC_FILES = index.ts lib/version.ts $(shell find lib -type f -name '*.ts')
 TEST_FILES = $(shell find test -type f -name '*.ts')
-BUILD_FILES = $(addprefix $(DIST_DIR)/, $(MOD).cjs.js $(MOD).esm.js $(MOD).min.js $(MOD).js)
+BUILD_FILES = $(addprefix $(DIST_DIR)/, $(MOD).cjs $(MOD).esm.js $(MOD).min.js $(MOD).js)
 
 .PHONY: all bench clean test dist lint build release node_modules
 
diff --git a/build.ts b/build.ts
index 09bc131c..3ce23d1e 100644
--- a/build.ts
+++ b/build.ts
@@ -19,7 +19,7 @@ async function build(): Promise<void> {
     // 1. CommonJS (CJS) - For Node.js `require()`
     await esbuild({
         ...sharedConfig,
-        outfile: 'dist/graphlib.cjs.js',
+        outfile: 'dist/graphlib.cjs',
         format: 'cjs',
         platform: 'node',
     });
diff --git a/dist/graphlib.cjs.js b/dist/graphlib.cjs
similarity index 99%
rename from dist/graphlib.cjs.js
rename to dist/graphlib.cjs
index c7495cbb..884a9e00 100644
--- a/dist/graphlib.cjs.js
+++ b/dist/graphlib.cjs
@@ -1,2 +1,2 @@
 "use strict";var F=Object.defineProperty;var H=Object.getOwnPropertyDescriptor;var U=Object.getOwnPropertyNames;var Y=Object.prototype.hasOwnProperty;var x=(s,e)=>{for(var t in e)F(s,t,{get:e[t],enumerable:!0})},z=(s,e,t,r)=>{if(e&&typeof e=="object"||typeof e=="function")for(let i of U(e))!Y.call(s,i)&&i!==t&&F(s,i,{get:()=>e[i],enumerable:!(r=H(e,i))||r.enumerable});return s};var K=s=>z(F({},"__esModule",{value:!0}),s);var oe={};x(oe,{Graph:()=>l,alg:()=>v,json:()=>y,version:()=>I});module.exports=K(oe);var l=class{constructor(e){this._isDirected=!0;this._isMultigraph=!1;this._isCompound=!1;this._nodes={};this._in={};this._preds={};this._out={};this._sucs={};this._edgeObjs={};this._edgeLabels={};this._nodeCount=0;this._edgeCount=0;this._defaultNodeLabelFn=()=>{};this._defaultEdgeLabelFn=()=>{};e&&(this._isDirected="directed"in e?e.directed:!0,this._isMultigraph="multigraph"in e?e.multigraph:!1,this._isCompound="compound"in e?e.compound:!1),this._isCompound&&(this._parent={},this._children={},this._children["\0"]={})}isDirected(){return this._isDirected}isMultigraph(){return this._isMultigraph}isCompound(){return this._isCompound}setGraph(e){return this._label=e,this}graph(){return this._label}setDefaultNodeLabel(e){return typeof e!="function"?this._defaultNodeLabelFn=()=>e:this._defaultNodeLabelFn=e,this}nodeCount(){return this._nodeCount}nodes(){return Object.keys(this._nodes)}sources(){return this.nodes().filter(e=>Object.keys(this._in[e]).length===0)}sinks(){return this.nodes().filter(e=>Object.keys(this._out[e]).length===0)}setNodes(e,t){return e.forEach(r=>{t!==void 0?this.setNode(r,t):this.setNode(r)}),this}setNode(e,t){return e in this._nodes?(arguments.length>1&&(this._nodes[e]=t),this):(this._nodes[e]=arguments.length>1?t:this._defaultNodeLabelFn(e),this._isCompound&&(this._parent[e]="\0",this._children[e]={},this._children["\0"][e]=!0),this._in[e]={},this._preds[e]={},this._out[e]={},this._sucs[e]={},++this._nodeCount,this)}node(e){return this._nodes[e]}hasNode(e){return e in this._nodes}removeNode(e){if(e in this._nodes){let t=r=>this.removeEdge(this._edgeObjs[r]);delete this._nodes[e],this._isCompound&&(this._removeFromParentsChildList(e),delete this._parent[e],this.children(e).forEach(r=>{this.setParent(r)}),delete this._children[e]),Object.keys(this._in[e]).forEach(t),delete this._in[e],delete this._preds[e],Object.keys(this._out[e]).forEach(t),delete this._out[e],delete this._sucs[e],--this._nodeCount}return this}setParent(e,t){if(!this._isCompound)throw new Error("Cannot set parent in a non-compound graph");if(t===void 0)t="\0";else{t+="";for(let r=t;r!==void 0;r=this.parent(r))if(r===e)throw new Error("Setting "+t+" as parent of "+e+" would create a cycle");this.setNode(t)}return this.setNode(e),this._removeFromParentsChildList(e),this._parent[e]=t,this._children[t][e]=!0,this}parent(e){if(this._isCompound){let t=this._parent[e];if(t!=="\0")return t}}children(e="\0"){if(this._isCompound){let t=this._children[e];if(t)return Object.keys(t)}else{if(e==="\0")return this.nodes();if(this.hasNode(e))return[]}return[]}predecessors(e){let t=this._preds[e];if(t)return Object.keys(t)}successors(e){let t=this._sucs[e];if(t)return Object.keys(t)}neighbors(e){let t=this.predecessors(e);if(t){let r=new Set(t),i=this.successors(e);if(i)for(let n of i)r.add(n);return Array.from(r.values())}}isLeaf(e){var r;let t;return this.isDirected()?t=this.successors(e):t=this.neighbors(e),((r=t==null?void 0:t.length)!=null?r:0)===0}filterNodes(e){let t=new 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"+n+"
"+(r===void 0?"\0":r)}function Q(s,e,t,r){let i=""+e,n=""+t;if(!s&&i>n){let d=i;i=n,n=d}let o={v:i,w:n};return r&&(o.name=r),o}function R(s,e){return _(s,e.v,e.w,e.name)}var I="4.0.4-pre";var y={};x(y,{read:()=>X,write:()=>$});function $(s){let e={options:{directed:s.isDirected(),multigraph:s.isMultigraph(),compound:s.isCompound()},nodes:q(s),edges:B(s)},t=s.graph();return t!==void 0&&(e.value=structuredClone(t)),e}function q(s){return s.nodes().map(e=>{let t=s.node(e),r=s.parent(e),i={v:e};return t!==void 0&&(i.value=t),r!==void 0&&(i.parent=r),i})}function B(s){return s.edges().map(e=>{let t=s.edge(e),r={v:e.v,w:e.w};return e.name!==void 0&&(r.name=e.name),t!==void 0&&(r.value=t),r})}function X(s){let e=new l(s.options);return s.value!==void 0&&e.setGraph(s.value),s.nodes.forEach(t=>{e.setNode(t.v,t.value),t.parent&&e.setParent(t.v,t.parent)}),s.edges.forEach(t=>{e.setEdge({v:t.v,w:t.w,name:t.name},t.value)}),e}var v={};x(v,{CycleException:()=>p,bellmanFord:()=>L,components:()=>D,dijkstra:()=>E,dijkstraAll:()=>O,findCycles:()=>j,floydWarshall:()=>C,isAcyclic:()=>T,postorder:()=>S,preorder:()=>M,prim:()=>V,shortestPaths:()=>J,tarjan:()=>w,topsort:()=>N});var Z=()=>1;function L(s,e,t,r){return ee(s,String(e),t||Z,r||function(i){var n;return(n=s.outEdges(i))!=null?n:[]})}function ee(s,e,t,r){let i={},n,o=0,d=s.nodes(),h=function(u){let g=i[u.v],f=i[u.w];if(!g||!f)return;let m=t(u);g.distance+m<f.distance&&(i[u.w]={distance:g.distance+m,predecessor:u.v},n=!0)},c=function(){d.forEach(function(u){r(u).forEach(function(g){let f=g.v===u?g.v:g.w,m=f===g.v?g.w:g.v;h({v:f,w:m})})})};d.forEach(function(u){let g=u===e?0:Number.POSITIVE_INFINITY;i[u]={distance:g,predecessor:""}});let a=d.length;for(let u=1;u<a&&(n=!1,o++,c(),!!n);u++);if(o===a-1&&(n=!1,c(),n))throw new Error("The graph contains a negative weight cycle");return i}function D(s){let e={},t=[],r;function i(n){var o,d;n in e||(e[n]=!0,r.push(n),(o=s.successors(n))==null||o.forEach(i),(d=s.predecessors(n))==null||d.forEach(i))}return s.nodes().forEach(function(n){r=[],i(n),r.length&&t.push(r)}),t}var b=class{constructor(){this._arr=[];this._keyIndices={}}size(){return this._arr.length}keys(){return this._arr.map(e=>e.key)}has(e){return e in this._keyIndices}priority(e){let t=this._keyIndices[e];if(t!==void 0)return this._arr[t].priority}min(){if(this.size()===0)throw new Error("Queue underflow");return this._arr[0].key}add(e,t){let r=this._keyIndices,i=String(e);if(!(i in r)){let n=this._arr,o=n.length;return r[i]=o,n.push({key:i,priority:t}),this._decrease(o),!0}return!1}removeMin(){if(this.size()===0)throw new Error("Queue underflow");this._swap(0,this._arr.length-1);let e=this._arr.pop();return delete this._keyIndices[e.key],this._heapify(0),e.key}decrease(e,t){let r=this._keyIndices[e];if(r===void 0)throw new Error(`Key not found: ${e}`);let i=this._arr[r].priority;if(t>i)throw new Error(`New priority is greater than current priority. 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Bad edge: "+c+" Weight: "+g);f<u.distance&&(u.distance=f,u.predecessor=o,n.decrease(a,f))};for(s.nodes().forEach(function(c){let a=c===e?0:Number.POSITIVE_INFINITY;i[c]={distance:a,predecessor:""},n.add(c,a)});n.size()>0;){o=n.removeMin();let c=i[o];if(!c||c.distance===Number.POSITIVE_INFINITY)break;d=c,r(o).forEach(h)}return i}function O(s,e,t){return s.nodes().reduce(function(r,i){return r[i]=E(s,i,e,t),r},{})}function w(s){let e=0,t=[],r={},i=[];function n(o){var h;let d=r[o]={onStack:!0,lowlink:e,index:e++};if(t.push(o),(h=s.successors(o))==null||h.forEach(function(c){if(c in r){let a=r[c];a!=null&&a.onStack&&(d.lowlink=Math.min(d.lowlink,a.index))}else{n(c);let a=r[c];a&&(d.lowlink=Math.min(d.lowlink,a.lowlink))}}),d.lowlink===d.index){let c=[],a;do{a=t.pop();let u=r[a];u&&(u.onStack=!1),c.push(a)}while(o!==a);i.push(c)}}return s.nodes().forEach(function(o){o in r||n(o)}),i}function j(s){return w(s).filter(function(e){var r;let t=e[0];return t?e.length>1||e.length===1&&((r=s.outEdges(t,t))!=null?r:[]).length>0:!1})}var ne=()=>1;function C(s,e,t){return ie(s,e||ne,t||function(r){var i;return(i=s.outEdges(r))!=null?i:[]})}function ie(s,e,t){let r={},i=s.nodes();return i.forEach(function(n){let o={};r[n]=o,o[n]={distance:0,predecessor:""},i.forEach(function(d){n!==d&&(o[d]={distance:Number.POSITIVE_INFINITY,predecessor:""})}),t(n).forEach(function(d){let h=d.v===n?d.w:d.v,c=e(d);o[h]={distance:c,predecessor:n}})}),i.forEach(function(n){let o=r[n];o&&i.forEach(function(d){let h=r[d];h&&i.forEach(function(c){let a=h[n],u=o[c],g=h[c];if(a&&u&&g){let f=a.distance+u.distance;f<g.distance&&(g.distance=f,g.predecessor=u.predecessor)}})})}),r}var p=class extends Error{constructor(e){super(e),this.name="CycleException"}};function N(s){let e={},t={},r=[];function i(n){var o;if(n in t)throw new p;n in e||(t[n]=!0,e[n]=!0,(o=s.predecessors(n))==null||o.forEach(i),delete t[n],r.push(n))}if(s.sinks().forEach(i),Object.keys(e).length!==s.nodeCount())throw new p;return r}function T(s){try{N(s)}catch(e){if(e instanceof p)return!1;throw e}return!0}function A(s,e,t,r,i){Array.isArray(e)||(e=[e]);let n=(d=>{var h;return(h=s.isDirected()?s.successors(d):s.neighbors(d))!=null?h:[]}),o={};return e.forEach(function(d){if(!s.hasNode(d))throw new Error("Graph does not have node: "+d);i=W(s,d,t==="post",o,n,r,i)}),i}function W(s,e,t,r,i,n,o){return e in r||(r[e]=!0,t||(o=n(o,e)),i(e).forEach(function(d){o=W(s,d,t,r,i,n,o)}),t&&(o=n(o,e))),o}function G(s,e,t){return A(s,e,t,function(r,i){return r.push(i),r},[])}function S(s,e){return G(s,e,"post")}function M(s,e){return G(s,e,"pre")}function V(s,e){var c;let t=new l,r={},i=new b,n;function o(a){let u=a.v===n?a.w:a.v,g=i.priority(u);if(g!==void 0){let f=e(a);f<g&&(r[u]=n,i.decrease(u,f))}}if(s.nodeCount()===0)return t;s.nodes().forEach(function(a){i.add(a,Number.POSITIVE_INFINITY),t.setNode(a)});let d=s.nodes()[0];d!==void 0&&i.decrease(d,0);let h=!1;for(;i.size()>0;){if(n=i.removeMin(),n in r)t.setEdge(n,r[n]);else{if(h)throw new Error("Input graph is not connected: "+s);h=!0}(c=s.nodeEdges(n))==null||c.forEach(o)}return t}function J(s,e,t,r){return se(s,e,t,r!=null?r:(i=>{var n;return(n=s.outEdges(i))!=null?n:[]}))}function se(s,e,t,r){if(t===void 0)return E(s,e,t,r);let i=!1,n=s.nodes();for(let o=0;o<n.length;o++){let d=n[o];if(d===void 0)continue;let h=r(d);for(let c=0;c<h.length;c++){let a=h[c];if(!a)continue;let u=a.v===d?a.v:a.w,g=u===a.v?a.w:a.v;t({v:u,w:g})<0&&(i=!0)}if(i)return L(s,e,t,r)}return E(s,e,t,r)}0&&(module.exports={Graph,alg,json,version});
-//# sourceMappingURL=graphlib.cjs.js.map
+//# sourceMappingURL=graphlib.cjs.map
diff --git a/dist/graphlib.cjs.js.map b/dist/graphlib.cjs.map
similarity index 100%
rename from dist/graphlib.cjs.js.map
rename to dist/graphlib.cjs.map
diff --git a/package.json b/package.json
index e6b63f8e..fe059def 100644
--- a/package.json
+++ b/package.json
@@ -7,7 +7,8 @@
     "David Newell"
   ],
   "license": "MIT",
-  "main": "dist/graphlib.cjs.js",
+  "type": "module",
+  "main": "dist/graphlib.cjs",
   "module": "dist/graphlib.esm.js",
   "scripts": {
     "build": "npm run build:types && tsx build.ts",
@@ -28,7 +29,7 @@
     ".": {
       "types": "./dist/types/index.d.ts",
       "import": "./dist/graphlib.esm.js",
-      "require": "./dist/graphlib.cjs.js"
+      "require": "./dist/graphlib.cjs"
     },
     "./package.json": "./package.json"
   },
diff --git a/test/dist-exports.test.ts b/test/dist-exports.test.ts
new file mode 100644
index 00000000..2ba2405d
--- /dev/null
+++ b/test/dist-exports.test.ts
@@ -0,0 +1,92 @@
+// Regression test for the published dist package format (dagrejs/graphlib #233).
+//
+// test/bundle-test.ts imports ../index (source) via ts-jest, so it cannot catch a
+// dist-format bug. This test exercises the BUILT dist bundles through real
+// runtimes (tsx for ESM, node for CJS) by importing them at an absolute path.
+//
+// Importing by absolute path is what makes this faithful: Node/tsx reads the
+// "type" field from the dist file's nearest package.json to decide whether a
+// ".js" file is ESM or CJS. Without "type": "module" the ESM bundle
+// (dist/graphlib.esm.js, ESM syntax) is treated as CJS, so named imports are
+// undefined and `new Graph()` throws. Adding "type": "module" fixes the ESM
+// path; renaming the CJS bundle to .cjs keeps `require()` working under it.
+
+import {execFileSync} from 'child_process';
+import {existsSync, mkdtempSync, rmSync, writeFileSync} from 'fs';
+import {tmpdir} from 'os';
+import {join, resolve} from 'path';
+
+const repoRoot = process.cwd();
+const esmPath = resolve(repoRoot, 'dist', 'graphlib.esm.js');
+const cjsPath = resolve(repoRoot, 'dist', 'graphlib.cjs');
+
+// ESM smoke check run under tsx — mirrors the #233 repro. Under a correct
+// package.json the named exports resolve; under the buggy format only `default`
+// is present, so `Graph` is undefined and `new Graph()` throws.
+const esmCheck = `import {Graph, alg, json, version} from ${JSON.stringify(esmPath)};
+
+const problems = [];
+if (typeof Graph !== 'function') problems.push('Graph is ' + typeof Graph + ', expected function');
+if (typeof alg !== 'object') problems.push('alg is ' + typeof alg + ', expected object');
+if (typeof json !== 'object') problems.push('json is ' + typeof json + ', expected object');
+if (typeof version !== 'string') problems.push('version is ' + typeof version + ', expected string');
+try {
+    const g = new Graph();
+    g.setNode('a');
+    if (!g.hasNode('a')) problems.push('Graph operation failed');
+} catch (e) {
+    problems.push('new Graph() threw: ' + e.message);
+}
+if (problems.length) { console.error('ESM FAIL: ' + problems.join('; ')); process.exit(1); }
+console.log('ESM OK');
+`;
+
+// CJS smoke check run under node — guards the CJS regression that a naive
+// "type": "module" (without renaming the CJS bundle to .cjs) would introduce:
+// `require()` of a .js file under "type": "module" throws ERR_REQUIRE_ESM.
+const cjsCheck = `const {Graph} = require(${JSON.stringify(cjsPath)});
+const g = new Graph();
+g.setNode('a');
+if (!g.hasNode('a')) { console.error('CJS FAIL: Graph operation failed'); process.exit(1); }
+console.log('CJS OK');
+`;
+
+describe('dist exports', () => {
+    let tmpDir: string;
+
+    beforeAll(() => {
+        if (!existsSync(esmPath) || !existsSync(cjsPath)) {
+            execFileSync('npm', ['run', 'build'], {
+                cwd: repoRoot,
+                stdio: 'pipe',
+                shell: process.platform === 'win32',
+            });
+        }
+        tmpDir = mkdtempSync(join(tmpdir(), 'graphlib-dist-exports-'));
+        writeFileSync(join(tmpDir, 'esm-check.mts'), esmCheck);
+        writeFileSync(join(tmpDir, 'cjs-check.cjs'), cjsCheck);
+    }, 60000);
+
+    afterAll(() => {
+        if (tmpDir) {
+            rmSync(tmpDir, {recursive: true, force: true});
+        }
+    });
+
+    it('ESM bundle exposes named exports under tsx', () => {
+        const out = execFileSync('npx', ['tsx', join(tmpDir, 'esm-check.mts')], {
+            cwd: repoRoot,
+            encoding: 'utf8',
+            shell: process.platform === 'win32',
+        });
+        expect(out).toContain('ESM OK');
+    }, 30000);
+
+    it('CJS bundle is requireable under node', () => {
+        const out = execFileSync(process.execPath, [join(tmpDir, 'cjs-check.cjs')], {
+            cwd: repoRoot,
+            encoding: 'utf8',
+        });
+        expect(out).toContain('CJS OK');
+    }, 30000);
+});