windows: search for a user-installed npm

This changes npm.cmd and the npm script when running in Cygwin to look
for an npm installation in prefix, running it if found. The default npm
is used to get the prefix. This implements the changes described in
https://github.com/joyent/node/issues/8528 .

Fixes joyent/node#8528. Reference: joyent/node#8554.

Fixes: #6412

PR-URL: https://github.com/npm/npm/pull/9089

2 files changed, 34 insertions, 8 deletions

diff --git a/bin/npm b/bin/npm
index d020ccfe7..45e8e4103 100755
--- a/bin/npm
+++ b/bin/npm
@@ -7,8 +7,21 @@ case `uname` in
     *CYGWIN*) basedir=`cygpath -w "$basedir"`;;
 esac
 
-if [ -x "$basedir/node.exe" ]; then
-  "$basedir/node.exe" "$basedir/node_modules/npm/bin/npm-cli.js" "$@"
-else
-  node "$basedir/node_modules/npm/bin/npm-cli.js" "$@"
+NODE_EXE="$basedir/node.exe"
+if ! [ -x "$NODE_EXE" ]; then
+  NODE_EXE=node
 fi
+
+NPM_CLI_JS="$basedir/node_modules/npm/bin/npm-cli.js"
+
+case `uname` in
+  *CYGWIN*)
+    NPM_PREFIX=`"$NODE_EXE" "$NPM_CLI_JS" prefix -g`
+    NPM_PREFIX_NPM_CLI_JS="$NPM_PREFIX/node_modules/npm/bin/npm-cli.js"
+    if [ -f "$NPM_PREFIX_NPM_CLI_JS" ]; then
+      NPM_CLI_JS="$NPM_PREFIX_NPM_CLI_JS"
+    fi
+    ;;
+esac
+
+"$NODE_EXE" "$NPM_CLI_JS" "$@"
diff --git a/bin/npm.cmd b/bin/npm.cmd
index 7720e2052..f111c59d1 100644
--- a/bin/npm.cmd
+++ b/bin/npm.cmd
@@ -1,6 +1,19 @@
 :: Created by npm, please don't edit manually.

-@IF EXIST "%~dp0\node.exe" (

-  "%~dp0\node.exe" "%~dp0\.\node_modules\npm\bin\npm-cli.js" %*

-) ELSE (

-  node "%~dp0\.\node_modules\npm\bin\npm-cli.js" %*

+@ECHO OFF

+

+SETLOCAL

+

+SET "NODE_EXE=%~dp0\node.exe"

+IF NOT EXIST "%NODE_EXE%" (

+  SET "NODE_EXE=node"

 )

+

+SET "NPM_CLI_JS=%~dp0\node_modules\npm\bin\npm-cli.js"

+FOR /F "delims=" %%F IN ('CALL "%NODE_EXE%" "%NPM_CLI_JS%" prefix -g') DO (

+  SET "NPM_PREFIX_NPM_CLI_JS=%%F\node_modules\npm\bin\npm-cli.js"

+)

+IF EXIST "%NPM_PREFIX_NPM_CLI_JS%" (

+  SET "NPM_CLI_JS=%NPM_PREFIX_NPM_CLI_JS%"

+)

+

+"%NODE_EXE%" "%NPM_CLI_JS%" %*