From 9607fb765720cdb7e21be16a3ffa27f9fca0c8be Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ma=C3=ABl=20Nison?= <mael@fb.com>
Date: Tue, 2 Oct 2018 11:32:54 +0100
Subject: [PATCH 1/2] Injects a "process.versions.pnp" variable

---
 CHANGELOG.md                         | 4 ++++
 src/util/generate-pnp-map-api.tpl.js | 2 ++
 2 files changed, 6 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index d82605fdce..39fa89e394 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -16,6 +16,10 @@ Please add one entry in this file for each change in Yarn's behavior. Use the sa
 
   [#6449](https://github.com/yarnpkg/yarn/pull/6449) - [**Maël Nison**](https://twitter.com/arcanis)
 
+- Makes the PnP hook inject a `process.versions.pnp` variable when setup (equals to `VERSIONS.std`)
+
+  [#6464](https://github.com/yarnpkg/yarn/pull/6464) - [**Maël Nison**](https://twitter.com/arcanis)
+
 - Fixes the display name of the faulty package when the NPM registry returns corrupted data
 
   [#6455](https://github.com/yarnpkg/yarn/pull/6455) - [**Grey Baker**](https://github.com/greysteil)
diff --git a/src/util/generate-pnp-map-api.tpl.js b/src/util/generate-pnp-map-api.tpl.js
index 1eeeab5cfa..d8f5152100 100644
--- a/src/util/generate-pnp-map-api.tpl.js
+++ b/src/util/generate-pnp-map-api.tpl.js
@@ -677,6 +677,8 @@ exports.setup = function setup() {
 
     return false;
   };
+
+  process.versions.pnp = String(exports.VERSIONS.std);
 };
 
 exports.setupCompatibilityLayer = () => {

From c59869998c3c2d0ca0d81b59a6e0654218dfd517 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ma=C3=ABl=20Nison?= <mael@fb.com>
Date: Tue, 2 Oct 2018 11:38:32 +0100
Subject: [PATCH 2/2] Adds a test

---
 packages/pkg-tests/pkg-tests-specs/sources/pnp.js | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/packages/pkg-tests/pkg-tests-specs/sources/pnp.js b/packages/pkg-tests/pkg-tests-specs/sources/pnp.js
index 7ef06f1c84..3c70197991 100644
--- a/packages/pkg-tests/pkg-tests-specs/sources/pnp.js
+++ b/packages/pkg-tests/pkg-tests-specs/sources/pnp.js
@@ -523,7 +523,7 @@ module.exports = makeTemporaryEnv => {
     test(
       `it should export the PnP API through the 'pnpapi' name`,
       makeTemporaryEnv(
-        {dependencies: {[`no-deps`]: `1.0.0`}},
+        {},
         {
           plugNPlay: true,
         },
@@ -535,6 +535,19 @@ module.exports = makeTemporaryEnv => {
       ),
     );
 
+    test(
+      `it should expose the PnP version through 'process.versions.pnp'`,
+      makeTemporaryEnv({}, {plugNPlay: true}, async ({path, run, source}) => {
+        await run(`install`);
+
+        const pnpapiVersionsStd = await source(`require('pnpapi').VERSIONS.std`);
+        const processVersionsPnp = await source(`process.versions.pnp`);
+
+        await expect(typeof processVersionsPnp).toEqual(`string`);
+        await expect(processVersionsPnp).toEqual(String(pnpapiVersionsStd));
+      }),
+    );
+
     test(
       `it should not update the installConfig.pnp field of the package.json when installing with an environment override`,
       makeTemporaryEnv(