From d044800b1f2de21f1c4452f22f23c3fd620fc08b Mon Sep 17 00:00:00 2001
From: Nathan Fisher <jeang3nie@hitchhiker-linux.org>
Date: Wed, 8 Jan 2025 15:10:39 -0500
Subject: [PATCH] Add ability to ignore whitespace characters during decoding

---
 README.md     |  2 +-
 src/decode.rs | 23 +++++++++++++++++------
 2 files changed, 18 insertions(+), 7 deletions(-)

diff --git a/README.md b/README.md
index e2f93c2..e0ccfbe 100644
--- a/README.md
+++ b/README.md
@@ -42,7 +42,7 @@ use {
 };
 
 fn main() {
-    let mut decoder = Decoder::new("SGVsbG8sIFdvcmxkIQ==".as_bytes(), vec![], None);
+    let mut decoder = Decoder::new("SGVsbG8sIFdvcmxkIQ==".as_bytes(), vec![], None, false);
     let output = decoder.decode().unwrap();
     assert_eq!(&output, b"Hello, World!");
 }
diff --git a/src/decode.rs b/src/decode.rs
index 4a5683a..4274b29 100644
--- a/src/decode.rs
+++ b/src/decode.rs
@@ -8,14 +8,16 @@ pub struct Decoder<R: Read, W: Write> {
     reader: R,
     writer: W,
     alphabet: B64Alphabet,
+    ignore_whitespace: bool,
 }
 
 impl<R: Read, W: Write> Decoder<R, W> {
-    pub fn new(reader: R, writer: W, alphabet: Option<B64Alphabet>) -> Self {
+    pub fn new(reader: R, writer: W, alphabet: Option<B64Alphabet>, ignore_whitespace: bool) -> Self {
         Self {
             reader,
             writer,
             alphabet: alphabet.unwrap_or_default(),
+            ignore_whitespace,
         }
     }
 
@@ -43,7 +45,9 @@ impl<R: Read, W: Write> Decoder<R, W> {
             while n_bytes < 4 {
                 match byte_reader.next() {
                     Some(Ok(b)) => {
-                        if b == b'\n' || b == b'\r' {
+                        if self.ignore_whitespace && b.is_ascii_whitespace() {
+                            continue;
+                        } else if b == b'\n' || b == b'\r' {
                             continue;
                         } else {
                             in_buf[n_bytes] = b;
@@ -98,19 +102,26 @@ mod tests {
 
     #[test]
     fn decode() {
-        let mut decoder = Decoder::new("SGVsbG8sIFdvcmxk".as_bytes(), vec![], None);
+        let mut decoder = Decoder::new("SGVsbG8sIFdvcmxk".as_bytes(), vec![], None, false);
         let mut output = decoder.decode().unwrap();
         assert_eq!(String::from_utf8(output.clone()).unwrap(), "Hello, World");
         output.clear();
-        decoder = Decoder::new("SGVsbG8sIFdvcmxkIQ==".as_bytes(), output, None);
+        decoder = Decoder::new("SGVsbG8sIFdvcmxkIQ==".as_bytes(), output, None, false);
         output = decoder.decode().unwrap();
         assert_eq!(String::from_utf8(output.clone()).unwrap(), "Hello, World!");
         output.clear();
-        decoder = Decoder::new("SGVsbG8sIFdvcmxkIQo=".as_bytes(), output, None);
+        decoder = Decoder::new("SGVsbG8sIFdvcmxkIQo=".as_bytes(), output, None, false);
         output = decoder.decode().unwrap();
         assert_eq!(String::from_utf8(output).unwrap(), "Hello, World!\n");
     }
 
+    #[test]
+    fn ignore_whitespace() {
+        let decoder = Decoder::new(" SG\tVsbG8sIFdvcmxkIQ==".as_bytes(), vec![], None, true);
+        let output = decoder.decode().unwrap();
+        assert_eq!(String::from_utf8(output.clone()).unwrap(), "Hello, World!");
+    }
+
     #[test]
     fn decode_wrapped() {
         let infile = File::open("src/testdata/lorem_b64.txt").unwrap();
@@ -120,7 +131,7 @@ mod tests {
             .unwrap()
             .read_to_end(&mut outfile)
             .unwrap();
-        let decoder = Decoder::new(reader, vec![], None);
+        let decoder = Decoder::new(reader, vec![], None, false);
         assert_eq!(decoder.decode().unwrap(), outfile);
     }
 }