redwoodjs
diff --git a/‎tasks/nmHoisting/README.md
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+60
diff --git a/‎tasks/nmHoisting/nmHoisting.mjs
+89 b/‎tasks/nmHoisting/nmHoisting.mjs
+89
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+# Nested `node_modules`
+
+When packages request different versions of the same dependency, Yarn tries to
+make both packages happy by installing two copies of that dependency. With a
+little bit of hand-waving here, for the `node-modules` linker, since dependencies
+have to exist at a single place on disk, Yarn has to decide which one gets
+hoisted to the top level (i.e. `node_modules/dependency`) and which one has to
+be nested
+(`node_modules/package-requesting-different-version/node_modules/dependency`).
+As far as I can tell, it does this in a more or less sensible way by hoisting
+the version that's requested the most.
+
+But when our own `@redwoodjs` packages become nested, it's usually a (painful)
+problem for us and for our users. This script identifies which of CRWA's
+dependencies have a lot of nested dependencies:
+
+```bash
+yarn node ./tasks/nmHoisting/nmHoisting.mjs
+```
+
+Here's a snippet of the nested dependencies for the `@redwoodjs` packages as of
+version `v6.5.1`:
+
+```json5
+{
+  "hoistedNodeModules": {
+    // ...
+    "@redwoodjs/internal": {
+      "source-map": "0.7.4"
+    },
+    "@redwoodjs/cli": {
+      "decamelize": "5.0.1"
+    },
+    "@redwoodjs/testing": {
+      "@types/node": "18.18.9"
+    },
+    "@redwoodjs/api": {
+      "@whatwg-node/fetch": "0.9.14"
+    },
+    "@redwoodjs/telemetry": {
+      "@whatwg-node/fetch": "0.9.14"
+    },
+    "@redwoodjs/prerender": {
+      "@whatwg-node/fetch": "0.9.14"
+    },
+    "@redwoodjs/structure": {
+      "lru-cache": "7.18.3"
+    },
+    "@redwoodjs/graphql-server": {
+      "@graphql-tools/utils": "10.0.11",
+      "@graphql-tools/utils/cjs": "null",
+      "@graphql-tools/schema": "10.0.2",
+      "@graphql-tools/schema/cjs": "null"
+    },
+    // ...
+  }
+}
+```
+
+You can also see a visualization by opening [nmHoistingVisualize.html](./nmHoistingVisualize.html):
@@ -0,0 +1,89 @@
+#!/usr/bin/env node
+/* eslint-env node */
+// @ts-check
+
+import { cd, fs, os, path, within, $ } from 'zx'
+
+async function main() {
+  const TMP_DIR = os.tmpdir()
+  const TIMESTAMP = (await $`date +%Y%m%d_%H%M%S`).stdout.trim()
+  let CRWA_DIR = path.join(`crwa_${TIMESTAMP}`)
+
+  const projectProvided = !!process.argv[2]
+
+  if (projectProvided) {
+    CRWA_DIR = process.argv[2]
+  }
+
+  let data = {
+    version: '',
+    node_modules: [],
+  }
+
+  await within(async () => {
+    cd(TMP_DIR)
+
+    if (!projectProvided) {
+      await $`yarn create redwood-app ${CRWA_DIR} -y`
+    }
+
+    cd(CRWA_DIR)
+
+    data.version = (
+      await $`jq -r '.devDependencies."@redwoodjs/core"' < package.json`
+    ).stdout.trim()
+
+    let stdout = (
+      await $`find ./node_modules -mindepth 2 -maxdepth 3 -type d -name node_modules`
+    ).stdout
+      .trim()
+      .split('\n')
+
+    data.node_modules = await batchLines(stdout)
+  })
+
+  const dataS = `\
+
+rawData.push(\`${JSON.stringify(data, null, 2)}\`)
+`
+
+  await fs.appendFile(new URL(`nmHoistingData.js`, import.meta.url), dataS)
+}
+
+main()
+
+// ------------------------
+// Helpers
+// ------------------------
+
+function batchLines(lines) {
+  return lines.reduce(async (objP, line) => {
+    const obj = await objP
+
+    let depLines = (await $`find ${line} -name 'package.json'`).stdout
+      .trim()
+      .split('\n')
+
+    const name = line.match(
+      /^\.\/node_modules\/(?<package>.+)\/node_modules$/
+    )[1]
+    obj[name] = await batchDepLines(depLines)
+
+    return obj
+  }, Promise.resolve({}))
+}
+
+function batchDepLines(depLines) {
+  return depLines.reduce(async (objP, depLine) => {
+    const obj = await objP
+
+    const version = (await $`cat ${depLine} | jq -r .version`).stdout.trim()
+
+    const name = depLine.match(
+      /[^\.]+\/node_modules\/(?<package>.+)\/package.json$/
+    )[1]
+    obj[name] = version
+
+    return obj
+  }, Promise.resolve({}))
+}