Add TIFF compression and corresponding tests

src/error.rs

@@ -10,6 +10,8 @@ use crate::tags::{
 };
 use crate::ColorType;
 
+use crate::weezl::LzwError;
+
 /// Tiff error kinds.
 #[derive(Debug)]
 pub enum TiffError {
@@ -31,6 +33,9 @@ pub enum TiffError {
 
     /// The image does not support the requested operation
     UsageError(UsageError),
+
+    /// An error has occurred during data compression
+    CompressionError,
 }
 
 /// The image is not formatted properly.
@@ -228,6 +233,7 @@ impl fmt::Display for TiffError {
             TiffError::LimitsExceeded => write!(fmt, "The Decoder limits are exceeded"),
             TiffError::IntSizeError => write!(fmt, "Platform or format size limits exceeded"),
             TiffError::UsageError(ref e) => write!(fmt, "Usage error: {}", e),
+            TiffError::CompressionError => write!(fmt, "Compression failed"),
         }
     }
 }
@@ -241,6 +247,7 @@ impl Error for TiffError {
             TiffError::LimitsExceeded => "Decoder limits exceeded",
             TiffError::IntSizeError => "Platform or format size limits exceeded",
             TiffError::UsageError(..) => "Invalid usage",
+            TiffError::CompressionError => "Compression failed",
         }
     }
 
@@ -288,5 +295,11 @@ impl From<std::num::TryFromIntError> for TiffError {
     }
 }
 
+impl From<LzwError> for TiffError {
+    fn from(_err: LzwError) -> TiffError {
+        TiffError::CompressionError
+    }
+}
+
 /// Result of an image decoding/encoding process
 pub type TiffResult<T> = Result<T, TiffError>;