Use the package.json data in the installation

So to verify the version of node in use.  Note that this install.sh
can't be deployed until AFTER this node is published.

3 files changed, 83 insertions, 8 deletions

diff --git a/bin/read-package-json.js b/bin/read-package-json.js
new file mode 100644
index 000000000..84944df72
--- /dev/null
+++ b/bin/read-package-json.js
@@ -0,0 +1,18 @@
+var argv = process.argv
+if (argv.length < 3) {
+  console.error("Usage: read-package.json <file> [<fields> ...]")
+  process.exit(1)
+}
+var fs = require("fs")
+  , file = argv[2]
+  , data = JSON.parse(fs.readFileSync(file, "utf8"))
+
+if (argv.length === 3) console.log(data)
+else argv.slice(3).forEach(function (field) {
+  field = field.split(".")
+  var val = data
+  field.forEach(function (f) {
+    val = val[f]
+  })
+  console.log(val)
+})
diff --git a/bin/semver.js b/bin/semver.js
new file mode 100644
index 000000000..5261de134
--- /dev/null
+++ b/bin/semver.js
@@ -0,0 +1,62 @@
+// Standalone semver comparison program.
+// Exits successfully and prints matching version(s) if
+// any supplied version is valid and passes all tests.
+
+var argv = process.argv.slice(2)
+  , versions = []
+  , range = []
+  , gt = []
+  , lt = []
+  , eq = []
+  , semver = require("../lib/utils/semver")
+
+main()
+
+function main () {
+  if (!argv.length) return help()
+  while (argv.length) {
+    switch (argv.shift()) {
+      case "-v": case "--version":
+        versions.push(argv.shift())
+        break
+      case "-r" : case "--range":
+        range.push(argv.shift())
+        break
+      default:
+        return help()
+    }
+  }
+  versions = versions.filter(semver.valid)
+  for (var i = 0, l = range.length; i < l ; i ++) {
+    versions = versions.filter(function (v) {
+      return semver.satisfies(v, range[i])
+    })
+    if (!versions.length) return fail()
+  }
+  return success(versions)
+}
+
+function fail () { process.exit(1) }
+
+function success () {
+  versions.sort(semver.compare).forEach(function (v,i,_) { console.log(v) })
+}
+
+function help () {
+  console.log(["Usage: semver -v <version> [-r <range>]"
+              ,"Test if version(s) satisfy the supplied range(s),"
+              ,"and sort them."
+              ,""
+              ,"Multiple versions or ranges may be supplied."
+              ,""
+              ,"Program exits successfully if all versions satisfy all"
+              ,"ranges and are valid, and prints all satisfying versions."
+              ,"If no versions are valid, or ranges are not satisfied,"
+              ,"then exits failure."
+              ,""
+              ,"Versions are printed in ascending order, so supplying"
+              ,"multiple versions to the utility will just sort them."
+              ].join("\n"))
+}
+
+
diff --git a/scripts/install.sh b/scripts/install.sh
index c9deb7787..8cbd0e4c4 100755
--- a/scripts/install.sh
+++ b/scripts/install.sh
@@ -36,20 +36,15 @@ if [ $? -ne 0 ] || ! [ -x $egrep ]; then
   egrep=egrep
 fi
 
-# TODO: Add cli interfaces to lib/utils/semver.js and lib/utils/read-json.js,
-# and pull the required node version out of the package.json
-# then do something like this:
-# ./bin/semver \
-#   -v `node --version 2>&1` \
-#   -r `./bin/read-json package.json engines.node`
 node_version=`$node --version 2>&1`
 ret=$?
 if [ $ret -eq 0 ]; then
-  echo $node_version | $egrep -v -q '^v?0\.([01]\.|2\.[0-2][^0-9])'
+  req=`$node bin/read-package-json.js package.json engines.node`
+  $node bin/semver.js -v "$node_version" -r "$req"
   ret=$?
 fi
 if [ $ret -ne 0 ]; then
-  echo "You need node v0.2.3 or higher to run this program." >&2
+  echo "You need node $req to run this program." >&2
   echo "node --version reports: $node_version" >&2
   echo "Please upgrade node before continuing."
   exit $ret