Use a YamlDecoder builder to implement optional encoding_trap parameter.

src/yaml.rs

@@ -210,22 +210,42 @@ impl YamlLoader {
         parser.load(&mut loader, true)?;
         Ok(loader.docs)
     }
+}
 
-    pub fn load_from_bytes(mut source: impl std::io::Read) -> Result<Vec<Yaml>, LoadError> {
-        let mut buffer = Vec::new();
-        source.read_to_end(&mut buffer)?;
-
-        // Decodes the input buffer using either UTF-8, UTF-16LE or UTF-16BE depending on the BOM codepoint.
-        // If the buffer doesn't start with a BOM codepoint, it will use a fallback encoding obtained by
-        // detect_utf16_endianness.
-        let (res, _) = encoding::types::decode(
-            &buffer,
-            encoding::DecoderTrap::Strict,
-            detect_utf16_endianness(&buffer),
-        );
-        let s = res.map_err(LoadError::Decode)?;
-        YamlLoader::load_from_str(&s).map_err(LoadError::Scan)
+pub struct YamlDecoder<T: std::io::Read> {
+  source: T,
+  trap: encoding::types::DecoderTrap,
+}
+
+
+impl<T: std::io::Read> YamlDecoder<T> {
+  pub fn read(source: T) -> YamlDecoder<T> {
+    YamlDecoder{
+      source: source,
+      trap: encoding::DecoderTrap::Strict,
     }
+  }
+
+  pub fn encoding_trap(mut self, trap: encoding::types::DecoderTrap) -> YamlDecoder<T> {
+    self.trap = trap;
+    self
+  }
+
+  pub fn decode(mut self) -> Result<Vec<Yaml>, LoadError> {
+    let mut buffer = Vec::new();
+    self.source.read_to_end(&mut buffer)?;
+
+    // Decodes the input buffer using either UTF-8, UTF-16LE or UTF-16BE depending on the BOM codepoint.
+    // If the buffer doesn't start with a BOM codepoint, it will use a fallback encoding obtained by
+    // detect_utf16_endianness.
+    let (res, _) = encoding::types::decode(
+        &buffer,
+        self.trap,
+        detect_utf16_endianness(&buffer),
+    );
+    let s = res.map_err(LoadError::Decode)?;
+    YamlLoader::load_from_str(&s).map_err(LoadError::Scan)
+  }
 }
 
 /// The encoding crate knows how to tell apart UTF-8 from UTF-16LE and utf-16BE, when the
@@ -793,7 +813,7 @@ a: 1
 b: 2.2
 c: [1, 2]
 ";
-        let out = YamlLoader::load_from_bytes(s as &[u8]).unwrap();
+        let out = YamlDecoder::read(s as &[u8]).decode().unwrap();
         let doc = &out[0];
         assert_eq!(doc["a"].as_i64().unwrap(), 1i64);
         assert_eq!(doc["b"].as_f64().unwrap(), 2.2f64);
@@ -808,7 +828,7 @@ c: [1, 2]
 \x00b\x00:\x00 \x002\x00.\x002\x00
 \x00c\x00:\x00 \x00[\x001\x00,\x00 \x002\x00]\x00
 \x00";
-        let out = YamlLoader::load_from_bytes(s as &[u8]).unwrap();
+        let out = YamlDecoder::read(s as &[u8]).decode().unwrap();
         let doc = &out[0];
         println!("GOT: {:?}", doc);
         assert_eq!(doc["a"].as_i64().unwrap(), 1i64);
@@ -824,7 +844,7 @@ c: [1, 2]
 \x00b\x00:\x00 \x002\x00.\x002\x00
 \x00c\x00:\x00 \x00[\x001\x00,\x00 \x002\x00]\x00
 ";
-        let out = YamlLoader::load_from_bytes(s as &[u8]).unwrap();
+        let out = YamlDecoder::read(s as &[u8]).decode().unwrap();
         let doc = &out[0];
         println!("GOT: {:?}", doc);
         assert_eq!(doc["a"].as_i64().unwrap(), 1i64);
@@ -840,7 +860,23 @@ c: [1, 2]
 \x00b\x00:\x00 \x002\x00.\x002\x00
 \x00c\x00:\x00 \x00[\x001\x00,\x00 \x002\x00]\x00
 \x00";
-        let out = YamlLoader::load_from_bytes(s as &[u8]).unwrap();
+        let out = YamlDecoder::read(s as &[u8]).decode().unwrap();
+        let doc = &out[0];
+        println!("GOT: {:?}", doc);
+        assert_eq!(doc["a"].as_i64().unwrap(), 1i64);
+        assert_eq!(doc["b"].as_f64().unwrap(), 2.2f64);
+        assert_eq!(doc["c"][1].as_i64().unwrap(), 2i64);
+        assert!(doc["d"][0].is_badvalue());
+    }
+
+    #[test]
+    fn test_read_trap() {
+        let s = b"---
+a\xa9: 1
+b: 2.2
+c: [1, 2]
+";
+        let out = YamlDecoder::read(s as &[u8]).encoding_trap(encoding::DecoderTrap::Ignore).decode().unwrap();
         let doc = &out[0];
         println!("GOT: {:?}", doc);
         assert_eq!(doc["a"].as_i64().unwrap(), 1i64);