From 9517b0de4a59b9a2334d5a9771a1cf442ba186e8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jimmy=20Wa=CC=88rting?= <jimmy@warting.se>
Date: Thu, 10 Mar 2022 11:47:05 +0100
Subject: [PATCH 1/5] fix: avoid reading files when the size is empty

---
 from.js               | 11 +++++++----
 test/own-misc-test.js |  6 ++++++
 2 files changed, 13 insertions(+), 4 deletions(-)

diff --git a/from.js b/from.js
index 9eaf8bf..a59da3a 100644
--- a/from.js
+++ b/from.js
@@ -82,13 +82,16 @@ class BlobDataItem {
 
   async * stream () {
     const { mtimeMs } = await stat(this.#path)
+    const start = this.#start
+    const end = start + this.size - 1
+
     if (mtimeMs > this.lastModified) {
       throw new DOMException('The requested file could not be read, typically due to permission problems that have occurred after a reference to a file was acquired.', 'NotReadableError')
     }
-    yield * createReadStream(this.#path, {
-      start: this.#start,
-      end: this.#start + this.size - 1
-    })
+
+    if (end > start) {
+      yield * createReadStream(this.#path, { start, end })
+    }
   }
 
   get [Symbol.toStringTag] () {
diff --git a/test/own-misc-test.js b/test/own-misc-test.js
index 999837d..abb6fe2 100644
--- a/test/own-misc-test.js
+++ b/test/own-misc-test.js
@@ -189,6 +189,12 @@ promise_test(async () => {
   assert_equals(await (await fileFrom('./LICENSE')).text(), license.toString())
 }, 'blob part backed up by filesystem slice correctly')
 
+promise_test(async () => {
+  fs.writeFileSync('temp', '')
+  await blobFromSync('./temp').text()
+  fs.unlinkSync('./temp')
+}, 'can read empty files')
+
 test(async () => {
   const blob = blobFromSync('./LICENSE')
   await new Promise(resolve => setTimeout(resolve, 2000))

From 68f88e20fb863742d3f3f8a9d9c90c03c134bb0b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jimmy=20Wa=CC=88rting?= <jimmy@warting.se>
Date: Thu, 10 Mar 2022 12:00:25 +0100
Subject: [PATCH 2/5] also use stat.size for checking if it is modified

---
 from.js | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/from.js b/from.js
index a59da3a..a9cb632 100644
--- a/from.js
+++ b/from.js
@@ -65,6 +65,9 @@ class BlobDataItem {
     this.#start = options.start
     this.size = options.size
     this.lastModified = options.lastModified
+    this.originalSize = options.originalSize === undefined
+      ? options.size
+      : options.originalSize
   }
 
   /**
@@ -75,17 +78,18 @@ class BlobDataItem {
     return new BlobDataItem({
       path: this.#path,
       lastModified: this.lastModified,
+      originalSize: this.originalSize,
       size: end - start,
       start: this.#start + start
     })
   }
 
   async * stream () {
-    const { mtimeMs } = await stat(this.#path)
+    const { mtimeMs, size } = await stat(this.#path)
     const start = this.#start
     const end = start + this.size - 1
 
-    if (mtimeMs > this.lastModified) {
+    if (mtimeMs > this.lastModified || this.originalSize !== size) {
       throw new DOMException('The requested file could not be read, typically due to permission problems that have occurred after a reference to a file was acquired.', 'NotReadableError')
     }
 

From dfe7c96a2cc6a3a6d834949cc5f5d89231e75443 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jimmy=20Wa=CC=88rting?= <jimmy@warting.se>
Date: Thu, 10 Mar 2022 12:04:58 +0100
Subject: [PATCH 3/5] bump minor version number

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index cfedf63..cc91aa3 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
     "name": "fetch-blob",
-    "version": "3.1.4",
+    "version": "3.1.5",
     "description": "Blob & File implementation in Node.js, originally from node-fetch.",
     "main": "index.js",
     "type": "module",

From 568b3096b40ca2b1b489edde2f648caf84d9c527 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jimmy=20Wa=CC=88rting?= <jimmy@warting.se>
Date: Thu, 10 Mar 2022 12:15:53 +0100
Subject: [PATCH 4/5] Don't push empty chunks into the array (creates faster
 reads)

---
 index.js | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/index.js b/index.js
index 2542ac2..8a3809c 100644
--- a/index.js
+++ b/index.js
@@ -83,8 +83,12 @@ const _Blob = class Blob {
         part = encoder.encode(`${element}`)
       }
 
-      this.#size += ArrayBuffer.isView(part) ? part.byteLength : part.size
-      this.#parts.push(part)
+      const size = ArrayBuffer.isView(part) ? part.byteLength : part.size
+      // Avoid pushing empty parts into the array to better GC them
+      if (size) {
+        this.#size += size
+        this.#parts.push(part)
+      }
     }
 
     this.#endings = `${options.endings === undefined ? 'transparent' : options.endings}`

From d4632ad83e399f2b259a2a57b3f01be8bcbe7d1d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jimmy=20Wa=CC=88rting?= <jimmy@warting.se>
Date: Thu, 10 Mar 2022 12:19:27 +0100
Subject: [PATCH 5/5] reverted back to avoid making a if check

---
 from.js | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/from.js b/from.js
index a9cb632..33c4e7b 100644
--- a/from.js
+++ b/from.js
@@ -86,16 +86,15 @@ class BlobDataItem {
 
   async * stream () {
     const { mtimeMs, size } = await stat(this.#path)
-    const start = this.#start
-    const end = start + this.size - 1
 
     if (mtimeMs > this.lastModified || this.originalSize !== size) {
       throw new DOMException('The requested file could not be read, typically due to permission problems that have occurred after a reference to a file was acquired.', 'NotReadableError')
     }
 
-    if (end > start) {
-      yield * createReadStream(this.#path, { start, end })
-    }
+    yield * createReadStream(this.#path, {
+      start: this.#start,
+      end: this.#start + this.size - 1
+    })
   }
 
   get [Symbol.toStringTag] () {