From 69fe21a7ec45df526461c4bf308332344112169a Mon Sep 17 00:00:00 2001
From: Lovell Fuller <github@lovell.info>
Date: Fri, 16 Aug 2019 21:21:12 +0100
Subject: [PATCH] Ensure invalid resize width/height as options throw #1817

---
 docs/changelog.md   |  3 +++
 lib/resize.js       | 16 ++++++++++++----
 test/unit/resize.js | 12 ++++++++++++
 3 files changed, 27 insertions(+), 4 deletions(-)

diff --git a/docs/changelog.md b/docs/changelog.md
index 09d9306c..8373df11 100644
--- a/docs/changelog.md
+++ b/docs/changelog.md
@@ -9,6 +9,9 @@ Requires libvips v8.8.1.
 * Ensure `sharp.format.vips` is present and correct (filesystem only).
   [#1813](https://github.com/lovell/sharp/issues/1813)
 
+* Ensure invalid `width` and `height` provided as options to `resize` throw.
+  [#1817](https://github.com/lovell/sharp/issues/1817)
+
 * Allow use of 'heic' and 'heif' identifiers with `toFormat`.
   [#1834](https://github.com/lovell/sharp/pull/1834)
   [@jaubourg](https://github.com/jaubourg)
diff --git a/lib/resize.js b/lib/resize.js
index 215dec29..1cc3fea9 100644
--- a/lib/resize.js
+++ b/lib/resize.js
@@ -210,12 +210,20 @@ function resize (width, height, options) {
   }
   if (is.object(options)) {
     // Width
-    if (is.integer(options.width) && options.width > 0) {
-      this.options.width = options.width;
+    if (is.defined(options.width)) {
+      if (is.integer(options.width) && options.width > 0) {
+        this.options.width = options.width;
+      } else {
+        throw is.invalidParameterError('width', 'positive integer', options.width);
+      }
     }
     // Height
-    if (is.integer(options.height) && options.height > 0) {
-      this.options.height = options.height;
+    if (is.defined(options.height)) {
+      if (is.integer(options.height) && options.height > 0) {
+        this.options.height = options.height;
+      } else {
+        throw is.invalidParameterError('height', 'positive integer', options.height);
+      }
     }
     // Fit
     if (is.defined(options.fit)) {
diff --git a/test/unit/resize.js b/test/unit/resize.js
index ee6ed639..f9146e7c 100644
--- a/test/unit/resize.js
+++ b/test/unit/resize.js
@@ -87,6 +87,18 @@ describe('Resize dimensions', function () {
     }, /Expected positive integer for height but received 1.5 of type number/);
   });
 
+  it('Invalid width - via options', () => {
+    assert.throws(() => {
+      sharp().resize({ width: 1.5, height: 240 });
+    }, /Expected positive integer for width but received 1.5 of type number/);
+  });
+
+  it('Invalid height - via options', () => {
+    assert.throws(() => {
+      sharp().resize({ width: 320, height: 1.5 });
+    }, /Expected positive integer for height but received 1.5 of type number/);
+  });
+
   it('Invalid width - too large', function (done) {
     sharp(fixtures.inputJpg)
       .resize(0x4000, 1)