From 342b0c1bbcfdcda300c66d9a9987b950594d45f9 Mon Sep 17 00:00:00 2001
From: Jonas Jenwald <jonas.jenwald@gmail.com>
Date: Tue, 27 Apr 2021 13:04:07 +0200
Subject: [PATCH] Move the `RunLengthStream` from `src/core/stream.js` and into
 its own file

---
 src/core/parser.js            |  2 +-
 src/core/run_length_stream.js | 67 +++++++++++++++++++++++++++++++++++
 src/core/stream.js            | 49 -------------------------
 3 files changed, 68 insertions(+), 50 deletions(-)
 create mode 100644 src/core/run_length_stream.js

diff --git a/src/core/parser.js b/src/core/parser.js
index 5c79654b0..a925aa947 100644
--- a/src/core/parser.js
+++ b/src/core/parser.js
@@ -19,7 +19,6 @@ import {
   FlateStream,
   NullStream,
   PredictorStream,
-  RunLengthStream,
 } from "./stream.js";
 import {
   assert,
@@ -47,6 +46,7 @@ import { Jbig2Stream } from "./jbig2_stream.js";
 import { JpegStream } from "./jpeg_stream.js";
 import { JpxStream } from "./jpx_stream.js";
 import { LZWStream } from "./lzw_stream.js";
+import { RunLengthStream } from "./run_length_stream.js";
 
 const MAX_LENGTH_TO_CACHE = 1000;
 const MAX_ADLER32_LENGTH = 5552;
diff --git a/src/core/run_length_stream.js b/src/core/run_length_stream.js
new file mode 100644
index 000000000..22eb8d769
--- /dev/null
+++ b/src/core/run_length_stream.js
@@ -0,0 +1,67 @@
+/* Copyright 2012 Mozilla Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+/* eslint-disable no-var */
+
+import { DecodeStream } from "./stream.js";
+
+var RunLengthStream = (function RunLengthStreamClosure() {
+  // eslint-disable-next-line no-shadow
+  function RunLengthStream(str, maybeLength) {
+    this.str = str;
+    this.dict = str.dict;
+
+    DecodeStream.call(this, maybeLength);
+  }
+
+  RunLengthStream.prototype = Object.create(DecodeStream.prototype);
+
+  RunLengthStream.prototype.readBlock = function RunLengthStream_readBlock() {
+    // The repeatHeader has following format. The first byte defines type of run
+    // and amount of bytes to repeat/copy: n = 0 through 127 - copy next n bytes
+    // (in addition to the second byte from the header), n = 129 through 255 -
+    // duplicate the second byte from the header (257 - n) times, n = 128 - end.
+    var repeatHeader = this.str.getBytes(2);
+    if (!repeatHeader || repeatHeader.length < 2 || repeatHeader[0] === 128) {
+      this.eof = true;
+      return;
+    }
+
+    var buffer;
+    var bufferLength = this.bufferLength;
+    var n = repeatHeader[0];
+    if (n < 128) {
+      // copy n bytes
+      buffer = this.ensureBuffer(bufferLength + n + 1);
+      buffer[bufferLength++] = repeatHeader[1];
+      if (n > 0) {
+        var source = this.str.getBytes(n);
+        buffer.set(source, bufferLength);
+        bufferLength += n;
+      }
+    } else {
+      n = 257 - n;
+      var b = repeatHeader[1];
+      buffer = this.ensureBuffer(bufferLength + n + 1);
+      for (var i = 0; i < n; i++) {
+        buffer[bufferLength++] = b;
+      }
+    }
+    this.bufferLength = bufferLength;
+  };
+
+  return RunLengthStream;
+})();
+
+export { RunLengthStream };
diff --git a/src/core/stream.js b/src/core/stream.js
index 258f0205e..54321d23a 100644
--- a/src/core/stream.js
+++ b/src/core/stream.js
@@ -1148,54 +1148,6 @@ var AsciiHexStream = (function AsciiHexStreamClosure() {
   return AsciiHexStream;
 })();
 
-var RunLengthStream = (function RunLengthStreamClosure() {
-  // eslint-disable-next-line no-shadow
-  function RunLengthStream(str, maybeLength) {
-    this.str = str;
-    this.dict = str.dict;
-
-    DecodeStream.call(this, maybeLength);
-  }
-
-  RunLengthStream.prototype = Object.create(DecodeStream.prototype);
-
-  RunLengthStream.prototype.readBlock = function RunLengthStream_readBlock() {
-    // The repeatHeader has following format. The first byte defines type of run
-    // and amount of bytes to repeat/copy: n = 0 through 127 - copy next n bytes
-    // (in addition to the second byte from the header), n = 129 through 255 -
-    // duplicate the second byte from the header (257 - n) times, n = 128 - end.
-    var repeatHeader = this.str.getBytes(2);
-    if (!repeatHeader || repeatHeader.length < 2 || repeatHeader[0] === 128) {
-      this.eof = true;
-      return;
-    }
-
-    var buffer;
-    var bufferLength = this.bufferLength;
-    var n = repeatHeader[0];
-    if (n < 128) {
-      // copy n bytes
-      buffer = this.ensureBuffer(bufferLength + n + 1);
-      buffer[bufferLength++] = repeatHeader[1];
-      if (n > 0) {
-        var source = this.str.getBytes(n);
-        buffer.set(source, bufferLength);
-        bufferLength += n;
-      }
-    } else {
-      n = 257 - n;
-      var b = repeatHeader[1];
-      buffer = this.ensureBuffer(bufferLength + n + 1);
-      for (var i = 0; i < n; i++) {
-        buffer[bufferLength++] = b;
-      }
-    }
-    this.bufferLength = bufferLength;
-  };
-
-  return RunLengthStream;
-})();
-
 var NullStream = (function NullStreamClosure() {
   // eslint-disable-next-line no-shadow
   function NullStream() {
@@ -1215,7 +1167,6 @@ export {
   FlateStream,
   NullStream,
   PredictorStream,
-  RunLengthStream,
   Stream,
   StreamsSequenceStream,
   StringStream,