ember-cli: Error on production build [Cannot read property '_walk' of null]

Hi all,

When building my project in production mode I’m getting Cannot read property '_walk' of null. This happens to a few of our projects and started happening a few days back.

Anyone else with this issue? Any ideas how to solve it?

Thanks

ENV Summary:

  TIME: Fri Sep 28 2018 10:27:46 GMT-0400 (Eastern Daylight Time)
  TITLE: ember
  ARGV:
  - /Users/z002fawe/.nvm/versions/node/v10.9.0/bin/node
  - /Users/z002fawe/.nvm/versions/node/v10.9.0/bin/ember
  - build
  - --environment=production
  EXEC_PATH: /Users/z002fawe/.nvm/versions/node/v10.9.0/bin/node
  TMPDIR: /var/folders/5g/tl5x1p1d15bbrv8fg4r1xmcw0000gn/T
  SHELL: /bin/bash
  PATH:
  - /usr/local/bin
  - /usr/bin
  - /bin
  - /usr/sbin
  - /sbin
  - /Applications/Wireshark.app/Contents/MacOS
  - /Applications/Postgres.app/Contents/Versions/10/bin/
  - /anaconda3/bin
  - /Users/z002fawe/.nvm/versions/node/v10.9.0/bin
  PLATFORM: darwin x64
  FREEMEM: 1813299200
  TOTALMEM: 17179869184
  UPTIME: 90110
  LOADAVG: 3.5947265625,2.98388671875,2.85546875
  CPUS:
  - Intel(R) Core(TM) i7-4770HQ CPU @ 2.20GHz - 2200
  - Intel(R) Core(TM) i7-4770HQ CPU @ 2.20GHz - 2200
  - Intel(R) Core(TM) i7-4770HQ CPU @ 2.20GHz - 2200
  - Intel(R) Core(TM) i7-4770HQ CPU @ 2.20GHz - 2200
  - Intel(R) Core(TM) i7-4770HQ CPU @ 2.20GHz - 2200
  - Intel(R) Core(TM) i7-4770HQ CPU @ 2.20GHz - 2200
  - Intel(R) Core(TM) i7-4770HQ CPU @ 2.20GHz - 2200
  - Intel(R) Core(TM) i7-4770HQ CPU @ 2.20GHz - 2200
  ENDIANNESS: LE
  VERSIONS:
  - ares: 1.14.0
  - cldr: 33.1
  - http_parser: 2.8.0
  - icu: 62.1
  - modules: 64
  - napi: 3
  - nghttp2: 1.32.0
  - node: 10.9.0
  - openssl: 1.1.0i
  - tz: 2018e
  - unicode: 11.0
  - uv: 1.22.0
  - v8: 6.8.275.24-node.14
  - zlib: 1.2.11

ERROR Summary:

  - broccoliBuilderErrorStack: TypeError: Cannot read property '_walk' of null
    at AST_Dot.eval (eval at <anonymous> (/Users/z002fawe/Projects/product-advisor/test/pa-aurora-frontend/node_modules/terser/tools/node.js:21:1), <anonymous>:1145:29)
    at TreeWalker._visit (eval at <anonymous> (/Users/z002fawe/Projects/product-advisor/test/pa-aurora-frontend/node_modules/terser/tools/node.js:21:1), <anonymous>:1546:21)
    at AST_Dot._walk (eval at <anonymous> (/Users/z002fawe/Projects/product-advisor/test/pa-aurora-frontend/node_modules/terser/tools/node.js:21:1), <anonymous>:1144:24)
    at AST_VarDef.eval (eval at <anonymous> (/Users/z002fawe/Projects/product-advisor/test/pa-aurora-frontend/node_modules/terser/tools/node.js:21:1), <anonymous>:1091:40)
    at TreeWalker._visit (eval at <anonymous> (/Users/z002fawe/Projects/product-advisor/test/pa-aurora-frontend/node_modules/terser/tools/node.js:21:1), <anonymous>:1546:21)
    at AST_VarDef._walk (eval at <anonymous> (/Users/z002fawe/Projects/product-advisor/test/pa-aurora-frontend/node_modules/terser/tools/node.js:21:1), <anonymous>:1089:24)
    at AST_Var.eval (eval at <anonymous> (/Users/z002fawe/Projects/product-advisor/test/pa-aurora-frontend/node_modules/terser/tools/node.js:21:1), <anonymous>:999:32)
    at TreeWalker._visit (eval at <anonymous> (/Users/z002fawe/Projects/product-advisor/test/pa-aurora-frontend/node_modules/terser/tools/node.js:21:1), <anonymous>:1546:21)
    at AST_Var._walk (eval at <anonymous> (/Users/z002fawe/Projects/product-advisor/test/pa-aurora-frontend/node_modules/terser/tools/node.js:21:1), <anonymous>:996:24)
    at walk_body (eval at <anonymous> (/Users/z002fawe/Projects/product-advisor/test/pa-aurora-frontend/node_modules/terser/tools/node.js:21:1), <anonymous>:510:17)
  - codeFrame: Cannot read property '_walk' of null
  - errorMessage: Build Canceled: Broccoli Builder ran into an error with `UglifyWriter` plugin. 💥
Cannot read property '_walk' of null
  - errorType: Build Error
  - location:
    - column: [undefined]
    - file: [undefined]
    - line: [undefined]
    - treeDir: [undefined]
  - message: Build Canceled: Broccoli Builder ran into an error with `UglifyWriter` plugin. 💥
Cannot read property '_walk' of null
  - name: Error
  - nodeAnnotation: UglifyWriter
  - nodeName: UglifyWriter
  - originalErrorMessage: Cannot read property '_walk' of null
  - stack: TypeError: Cannot read property '_walk' of null
    at AST_Dot.eval (eval at <anonymous> (/Users/z002fawe/Projects/product-advisor/test/pa-aurora-frontend/node_modules/terser/tools/node.js:21:1), <anonymous>:1145:29)
    at TreeWalker._visit (eval at <anonymous> (/Users/z002fawe/Projects/product-advisor/test/pa-aurora-frontend/node_modules/terser/tools/node.js:21:1), <anonymous>:1546:21)
    at AST_Dot._walk (eval at <anonymous> (/Users/z002fawe/Projects/product-advisor/test/pa-aurora-frontend/node_modules/terser/tools/node.js:21:1), <anonymous>:1144:24)
    at AST_VarDef.eval (eval at <anonymous> (/Users/z002fawe/Projects/product-advisor/test/pa-aurora-frontend/node_modules/terser/tools/node.js:21:1), <anonymous>:1091:40)
    at TreeWalker._visit (eval at <anonymous> (/Users/z002fawe/Projects/product-advisor/test/pa-aurora-frontend/node_modules/terser/tools/node.js:21:1), <anonymous>:1546:21)
    at AST_VarDef._walk (eval at <anonymous> (/Users/z002fawe/Projects/product-advisor/test/pa-aurora-frontend/node_modules/terser/tools/node.js:21:1), <anonymous>:1089:24)
    at AST_Var.eval (eval at <anonymous> (/Users/z002fawe/Projects/product-advisor/test/pa-aurora-frontend/node_modules/terser/tools/node.js:21:1), <anonymous>:999:32)
    at TreeWalker._visit (eval at <anonymous> (/Users/z002fawe/Projects/product-advisor/test/pa-aurora-frontend/node_modules/terser/tools/node.js:21:1), <anonymous>:1546:21)
    at AST_Var._walk (eval at <anonymous> (/Users/z002fawe/Projects/product-advisor/test/pa-aurora-frontend/node_modules/terser/tools/node.js:21:1), <anonymous>:996:24)
    at walk_body (eval at <anonymous> (/Users/z002fawe/Projects/product-advisor/test/pa-aurora-frontend/node_modules/terser/tools/node.js:21:1), <anonymous>:510:17)

=================================================================================

Output from ember version --verbose && npm --version && yarn --version:

ember-cli: 3.4.1
http_parser: 2.8.0
node: 10.9.0
v8: 6.8.275.24-node.14
uv: 1.22.0
zlib: 1.2.11
ares: 1.14.0
modules: 64
nghttp2: 1.32.0
napi: 3
openssl: 1.1.0i
icu: 62.1
unicode: 11.0
cldr: 33.1
tz: 2018e
os: darwin x64
6.4.1
1.6.0

About this issue

Original URL
State: closed
Created 6 years ago
Reactions: 6
Comments: 18 (7 by maintainers)

Commits related to this issue

fixing production build issue this https://github.com/ember-cli/ember-cli/issues/8075 — committed to aklkv/ember-website by aklkv 6 years ago
fixing production build issue this https://github.com/ember-cli/ember-cli/issues/8075 — committed to aklkv/ember-website by aklkv 6 years ago
fixing production build issue this https://github.com/ember-cli/ember-cli/issues/8075 — committed to aklkv/ember-website by aklkv 6 years ago
Fix (docs) Workaround for https://github.com/ember-cli/ember-cli/issues/8075 — committed to sauce-consultants/ember-ux-sauce by th3hamburgler 6 years ago
build(deploy): fix `TypeError: Cannot read property '_walk' of null` https://github.com/ember-cli/ember-cli/issues/8075#issuecomment-426046159 https://github.com/terser-js/terser/issues/120 — committed to alexdiliberto/ember-transformicons by alexdiliberto 5 years ago

Most upvoted comments

I’m working on the same problem in a completely different stack.

UPDATE: Hey @bajcmartinez and @guneetsinghbhatia I was able to get my build working by adding configuration for uglify-js! The relevant config change was as follows:

uglify({
  compress: {
    collapse_vars: false    <--- ADDED 
  }
})

Note that reduce_vars: false also got the build running again, but the artifact size was larger so I opted to stick with collapse for now. Also, this change was inspired by: https://github.com/mishoo/UglifyJS2/issues/1609

KyleCartmell on Sep 28, 2018

@rwjblue This is the snippet I used

# ember-cli-build.js
 module.exports = function (defaults) {
   const appConfig = {
...
      'ember-cli-uglify': {
        uglify: {
          compress: {
            collapse_vars: false
          }
        }
      },

@rwwagner90 check package-lock.json. In my case, I wasn’t using tether directly either, but I looked into that file and noticed it was required by ember-tooltips (i.e. ember-tooltips <- ember-tether <-tether

serchavalos on Oct 7, 2018