From 54e6924f742dfc46f1413c3cbdfeb1440c1ad8d9 Mon Sep 17 00:00:00 2001
From: Filipe Silva <filipematossilva@gmail.com>
Date: Tue, 2 Apr 2019 16:45:10 +0100
Subject: [PATCH] fix(@schematics/update): guard against null value for semver
 check

---
 packages/schematics/update/BUILD           | 1 +
 packages/schematics/update/update/index.ts | 8 +++++++-
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/packages/schematics/update/BUILD b/packages/schematics/update/BUILD
index 32deb0ba84..146f202f90 100644
--- a/packages/schematics/update/BUILD
+++ b/packages/schematics/update/BUILD
@@ -28,6 +28,7 @@ ts_library(
         "//packages/angular_devkit/schematics",
         "//packages/angular_devkit/schematics:tasks",
         "@npm//rxjs",
+        "@npm//semver",
         
         "@npm//@types/node",
         "@npm//@types/semver",
diff --git a/packages/schematics/update/update/index.ts b/packages/schematics/update/update/index.ts
index 48bc641fcf..7ac57a6e7f 100644
--- a/packages/schematics/update/update/index.ts
+++ b/packages/schematics/update/update/index.ts
@@ -528,7 +528,7 @@ function _buildPackageInfo(
 
   // Find out the currently installed version. Either from the package.json or the node_modules/
   // TODO: figure out a way to read package-lock.json and/or yarn.lock.
-  let installedVersion: string | undefined;
+  let installedVersion: string | undefined | null;
   const packageContent = tree.read(`/node_modules/${name}/package.json`);
   if (packageContent) {
     const content = JSON.parse(packageContent.toString()) as JsonSchemaForNpmPackageJsonFiles;
@@ -542,6 +542,12 @@ function _buildPackageInfo(
     );
   }
 
+  if (!installedVersion) {
+    throw new SchematicsException(
+      `An unexpected error happened; could not determine version for package ${name}.`,
+    );
+  }
+
   const installedPackageJson = npmPackageJson.versions[installedVersion] || packageContent;
   if (!installedPackageJson) {
     throw new SchematicsException(