Revert "[Fix] `nvm_die_on_prefix`: only grep lines starting with env var name" (#2347)

This reverts commit 21c0c05130.

Fixes #2360. Fixes #2364. Fixes #2366.

nvm.sh

@@ -2352,7 +2352,7 @@ nvm_die_on_prefix() {
   # here, we avoid trying to replicate "which one wins" or testing the value; if any are defined, it errors
   # until none are left.
   local NVM_NPM_CONFIG_PREFIX_ENV
-  NVM_NPM_CONFIG_PREFIX_ENV="$(command env | nvm_grep -i ^NPM_CONFIG_PREFIX | command tail -1 | command awk -F '=' '{print $1}')"
+  NVM_NPM_CONFIG_PREFIX_ENV="$(command env | nvm_grep -i NPM_CONFIG_PREFIX | command tail -1 | command awk -F '=' '{print $1}')"
   if [ -n "${NVM_NPM_CONFIG_PREFIX_ENV-}" ]; then
     local NVM_CONFIG_VALUE
     eval "NVM_CONFIG_VALUE=\"\$${NVM_NPM_CONFIG_PREFIX_ENV}\""

test/fast/Unit tests/nvm_die_on_prefix

@@ -84,9 +84,6 @@ EXIT_CODE="$(export npm_CONFIG_PREFIX=bar ; nvm_die_on_prefix 0 foo "$(nvm_versi
 [ "_$OUTPUT" = "_$EXPECTED_OUTPUT" ] || die "'npm_CONFIG_PREFIX=bar nvm_die_on_prefix 0 foo' did not error with '$EXPECTED_OUTPUT'; got '$OUTPUT'"
 [ "_$EXIT_CODE" = "_4" ] || die "'npm_CONFIG_PREFIX=bar nvm_die_on_prefix 0 foo' did not exit with 4; got '$EXIT_CODE'"
 
-OUTPUT="$(export FOO='NPM_CONFIG_PREFIX' ; nvm_die_on_prefix 0 foo "$(nvm_version_dir new)" 2>&1)"
-[ -z "$OUTPUT" ] || die "'nvm_die_on_prefix' was not a noop; got '$OUTPUT'"
-
 # npmrc tests
 (
   cd "${TEST_DIR}"