[BUG] npm install <dep>@versionOrTag does not honor save prefix

[aliatsis]

Current Behavior:

On the heels of #1849, npm v7.0.0-rc.0 does not include my configured ^ save prefix in devDependencies version when running an npm i <dep>@versionOrTag.

Expected Behavior:

npm i <dep>@versionOrTag should include my configured ^ save prefix on the updated version in package.json devDependencies

Steps To Reproduce:

1. Install npm v7.0.0-rc.0
2. npm i <dep>@prev-version where prev-version is the exact number version of a previous version
   3). observe no save prefix in package.json devDependencies for <dep>
   4). npm i <dep>@latest
   5). observe no save prefix in package.json devDependencies for <dep>

Environment:

Node: v10.15.3
NPM: v7.0.0-rc.0

[darcyclarke]

@aliatsis can you try testing if this is still a problem after installing the latest version? (ie. 7.0.15)

[aliatsis]

@darcyclarke I can still reproduce with 7.0.15

[wraithgar]

I was not able to reproduce this in npm v7.4.1

I tried with both an .npmrc file in the project folder, and my ~/.npmrc file. I tried with both setting save-prefix=~ and save-prefix=^ and also with no save-prefix (which fell back to the default which is save-prefix=^

In each case I started with a package.json with no dependencies. Then ran

$ npm install [email protected] -D
$ npm install lodash@latest

I also tried

$ npm install [email protected] -D
$ npm install lodash@latest

To test updating without crossing a semver major boundary

In each case, the expected prefix was present in my package.json file