pack: add dryRun option to packDirectory (#47)

Add dryRun option to packDirectory. This makes it possible to run postscript after the archive has been written to cwd.

Fixes: https://npm.community/t/592
PR-URL: #47
Credit: @larsgw
Reviewed-By: @zkat

Author: larsgw

Diff for: lib/pack.js

@@ -68,22 +68,13 @@ function pack_ (pkg, dir) {
       : mani.name
     const target = `${name}-${mani.version}.tgz`
     return pinflight(target, () => {
+      const dryRun = npm.config.get('dry-run')
       if (mani._requested.type === 'directory') {
-        return cacache.tmp.withTmp(npm.tmp, {tmpPrefix: 'packing'}, (tmp) => {
-          const tmpTarget = path.join(tmp, path.basename(target))
-          return prepareDirectory(mani._resolved)
-            .then(() => {
-              return packDirectory(mani, mani._resolved, tmpTarget, target, true)
-            })
-            .tap(() => {
-              if (npm.config.get('dry-run')) {
-                log.verbose('pack', '--dry-run mode enabled. Skipping write.')
-              } else {
-                return move(tmpTarget, target, {Promise: BB, fs})
-              }
-            })
-        })
-      } else if (npm.config.get('dry-run')) {
+        return prepareDirectory(mani._resolved)
+          .then(() => {
+            return packDirectory(mani, mani._resolved, target, target, true, dryRun)
+          })
+      } else if (dryRun) {
         log.verbose('pack', '--dry-run mode enabled. Skipping write.')
         return cacache.tmp.withTmp(npm.tmp, {tmpPrefix: 'packing'}, (tmp) => {
           const tmpTarget = path.join(tmp, path.basename(target))
@@ -137,7 +128,7 @@ function prepareDirectory (dir) {
 }
 
 module.exports.packDirectory = packDirectory
-function packDirectory (mani, dir, target, filename, logIt) {
+function packDirectory (mani, dir, target, filename, logIt, dryRun) {
   deprCheck(mani)
   return readJson(path.join(dir, 'package.json')).then((pkg) => {
     return lifecycle(pkg, 'prepack', dir)
@@ -165,7 +156,13 @@ function packDirectory (mani, dir, target, filename, logIt) {
         .then((files) => tar.create(tarOpt, files.map((f) => `./${f}`)))
         .then(() => getContents(pkg, tmpTarget, filename, logIt))
         // thread the content info through
-        .tap(() => move(tmpTarget, target, {Promise: BB, fs}))
+        .tap(() => {
+          if (dryRun) {
+            log.verbose('pack', '--dry-run mode enabled. Skipping write.')
+          } else {
+            return move(tmpTarget, target, {Promise: BB, fs})
+          }
+        })
         .tap(() => lifecycle(pkg, 'postpack', dir))
     })
   })

Diff for: test/tap/pack.js

@@ -165,3 +165,35 @@ test('pack --json', (t) => {
     })
     .then(() => rimraf(testDir))
 })
+
+test('postpack', (t) => {
+  const fixture = new Tacks(new Dir({
+    'package.json': new File({
+      name: 'generic-package',
+      version: '90000.100001.5',
+      scripts: {
+        postpack: 'node -e "var fs = require(\'fs\'); fs.openSync(\'postpack-step\', \'w+\'); if (!fs.existsSync(\'generic-package-90000.100001.5.tgz\')) { throw new Error(\'tar archive does not exist on postpack\') }"'
+      }
+    })
+  }))
+
+  return rimraf(testDir)
+    .then(() => fixture.create(testDir))
+    .then(() => common.npm([
+      'pack',
+      '--loglevel', 'notice',
+      '--cache', cache,
+      '--tmp', tmp,
+      '--prefix', testDir,
+      '--no-global'
+    ], {
+      cwd: testDir
+    }))
+    .spread((code, stdout, stderr) => {
+      t.equal(code, 0, 'npm pack exited ok')
+      return fs.statAsync(
+        path.join(testDir, 'postpack-step')
+      )
+    })
+    .then(() => rimraf(testDir))
+})