[BUG] npx crashes when mixing implicit/explicit modules in -p

[nikolaik]

Is there an existing issue for this?

• I have searched the existing issues

Current Behavior

Run the following npx command in a directory that has an existing node_modules with one of the modules already installed. When mixing implict and specific like below, npx crashes when it tries to tread undefined as a string.

$ npx -p [email protected] -p @babel/core gitmoji -l
npm ERR! Cannot read property 'replace' of undefined

Here is the stack trace from the debug log:

32 verbose stack TypeError: Cannot read property 'replace' of undefined
32 verbose stack     at .nvm/versions/node/v14.16.0/lib/node_modules/npm/node_modules/libnpmexec/lib/index.js:163:47
32 verbose stack     at Array.map (<anonymous>)
32 verbose stack     at exec (.nvm/versions/node/v14.16.0/lib/node_modules/npm/node_modules/libnpmexec/lib/index.js:163:31)

Not sure if it crashes because of the missing version specifier @babel/core when it already has a fixed version in package.json or something else.

Expected Behavior

Expect it to prompt for installation (the first time it is run):

$ npx -p [email protected] -p @babel/core@7 gitmoji -l
Need to install the following packages:
  @babel/core@7
  [email protected]
Ok to proceed? (y) 

Steps To Reproduce

# create a new dir with an empty package.json
mkdir fresh-dir && cd fresh-dir && npm init -y
npm i @babel/core
npx -p [email protected] -p @babel/core gitmoji -l

Environment

• OS: Ubuntu 21.04
• Node: 14.16.0
• npm: 7.21.0

[nlf]

#4643 fixes this issue /cc @ruyadorno

[ruyadorno]

moved the bit that fixes this issue to #4777