Lint: Use is_empty().

  - https://rust-lang.github.io/rust-clippy/master/index.html#len_zero

  - https://rust-lang.github.io/rust-clippy/master/index.html#comparison_to_empty

39 files changed, 96 insertions, 96 deletions

diff --git a/autocrypt/src/lib.rs b/autocrypt/src/lib.rs
index 5c2386cc..b3bebd65 100644
--- a/autocrypt/src/lib.rs
+++ b/autocrypt/src/lib.rs
@@ -239,7 +239,7 @@ impl AutocryptHeaders {
             // Return any error.
             let mut line = line?;
 
-            if line == "" {
+            if line.is_empty() {
                 // End of headers.
                 break;
             }
@@ -252,7 +252,7 @@ impl AutocryptHeaders {
             //
             // See https://tools.ietf.org/html/rfc5322#section-2.2.3
             while let Some(Ok(nl)) = next_line {
-                if nl.len() > 0 && (&nl[0..1] == " " || &nl[0..1] == "\t") {
+                if !nl.is_empty() && (&nl[0..1] == " " || &nl[0..1] == "\t") {
                     line.push_str(&nl[..]);
                     next_line = lines.next();
                 } else {
@@ -315,7 +315,7 @@ impl AutocryptHeaders {
                 }
             }
 
-            let critical = key.len() >= 1 && &key[0..1] == "_";
+            let critical = !key.is_empty() && &key[0..1] == "_";
             header.attributes.push(Attribute {
                 critical,
                 key: if critical {
@@ -571,7 +571,7 @@ impl AutocryptSetupMessage {
                     if k == "Passphrase-Format" { Some(v) } else { None }
                 })
                 .collect::<Vec<&String>>();
-            let format = if format.len() > 0 {
+            let format = if !format.is_empty() {
                 // If there are multiple headers, then just silently take
                 // the first one.
                 Some(format[0].clone())
@@ -584,7 +584,7 @@ impl AutocryptSetupMessage {
                     if k == "Passphrase-Begin" { Some(v) } else { None }
                 })
                 .collect::<Vec<&String>>();
-            let begin = if begin.len() > 0 {
+            let begin = if !begin.is_empty() {
                 // If there are multiple headers, then just silently take
                 // the first one.
                 Some(begin[0].clone())
@@ -754,7 +754,7 @@ impl<'a> AutocryptSetupMessageParser<'a> {
                         })
                         .collect::<Vec<&String>>();
 
-                    if prefer_encrypt.len() > 0 {
+                    if !prefer_encrypt.is_empty() {
                         // If there are multiple headers, then just
                         // silently take the first one.
                         Some(prefer_encrypt[0].clone())
diff --git a/buffered-reader/src/decompress_deflate.rs b/buffered-reader/src/decompress_deflate.rs
index d713413a..1bb0bc4f 100644
--- a/buffered-reader/src/decompress_deflate.rs
+++ b/buffered-reader/src/decompress_deflate.rs
@@ -294,7 +294,7 @@ mod test {
 
         for i in 0..input_raw.len() {
             let data = reader.data(DEFAULT_BUF_SIZE + 1).unwrap().to_vec();
-            assert!(data.len() > 0);
+            assert!(!data.is_empty());
             assert_eq!(data, reader.buffer());
             // And, we may as well check to make sure we read the
             // right data.
diff --git a/buffered-reader/src/dup.rs b/buffered-reader/src/dup.rs
index df4a6e2f..c63ab9c8 100644
--- a/buffered-reader/src/dup.rs
+++ b/buffered-reader/src/dup.rs
@@ -194,7 +194,7 @@ mod test {
 
         for i in 0..input.len() {
             let data = reader.data(DEFAULT_BUF_SIZE + 1).unwrap().to_vec();
-            assert!(data.len() > 0);
+            assert!(!data.is_empty());
             assert_eq!(data, reader.buffer());
             // And, we may as well check to make sure we read the
             // right data.
diff --git a/buffered-reader/src/generic.rs b/buffered-reader/src/generic.rs
index 19f799eb..aa72e1b4 100644
--- a/buffered-reader/src/generic.rs
+++ b/buffered-reader/src/generic.rs
@@ -351,7 +351,7 @@ mod test {
 
         for i in 0..input.len() {
             let data = reader.data(DEFAULT_BUF_SIZE + 1).unwrap().to_vec();
-            assert!(data.len() > 0);
+            assert!(!data.is_empty());
             assert_eq!(data, reader.buffer());
             // And, we may as well check to make sure we read the
             // right data.
diff --git a/buffered-reader/src/lib.rs b/buffered-reader/src/lib.rs
index 18fdbaee..ed5a4724 100644
--- a/buffered-reader/src/lib.rs
+++ b/buffered-reader/src/lib.rs
@@ -723,13 +723,13 @@ pub trait BufferedReader<C> : io::Read + fmt::Debug + fmt::Display + Send + Sync
             let len = {
                 // Try self.buffer.  Only if it is empty, use
                 // self.data.
-                let buffer = if self.buffer().len() == 0 {
+                let buffer = if self.buffer().is_empty() {
                     self.data(DEFAULT_BUF_SIZE)?
                 } else {
                     self.buffer()
                 };
 
-                if buffer.len() == 0 {
+                if buffer.is_empty() {
                     break 'outer 0;
                 }
 
@@ -1096,7 +1096,7 @@ mod test {
             {
                 let result = bio.data(buffer.len());
                 let buffer = result.unwrap();
-                if buffer.len() > 0 {
+                if !buffer.is_empty() {
                     assert_eq!(buffer,
                                &data[data_start..data_start + buffer.len()]);
                 }
diff --git a/buffered-reader/src/limitor.rs b/buffered-reader/src/limitor.rs
index c20edced..e7260c3b 100644
--- a/buffered-reader/src/limitor.rs
+++ b/buffered-reader/src/limitor.rs
@@ -266,7 +266,7 @@ mod test {
 
         for i in 0..input.len() {
             let data = reader.data(DEFAULT_BUF_SIZE + 1).unwrap().to_vec();
-            assert!(data.len() > 0);
+            assert!(!data.is_empty());
             assert_eq!(data, reader.buffer());
             // And, we may as well check to make sure we read the
             // right data.
diff --git a/buffered-reader/src/memory.rs b/buffered-reader/src/memory.rs
index a177c6c0..6fb9e338 100644
--- a/buffered-reader/src/memory.rs
+++ b/buffered-reader/src/memory.rs
@@ -167,7 +167,7 @@ mod test {
 
         for i in 0..input.len() {
             let data = reader.data(DEFAULT_BUF_SIZE + 1).unwrap().to_vec();
-            assert!(data.len() > 0);
+            assert!(!data.is_empty());
             assert_eq!(data, reader.buffer());
             // And, we may as well check to make sure we read the
             // right data.
diff --git a/ffi/tests/c-tests.rs b/ffi/tests/c-tests.rs
index 4dd5f616..40f82094 100644
--- a/ffi/tests/c-tests.rs
+++ b/ffi/tests/c-tests.rs
@@ -163,7 +163,7 @@ fn for_all_tests<F>(path: &Path, mut fun: F)
             }
 
             if let Some(name) = exported_function_name(&line) {
-                if test.len() > 0 {
+                if !test.is_empty() {
                     fun(path, test_starts_at, &name, replace(&mut test, vec![]),
                         run)?;
                     test.clear();
@@ -175,7 +175,7 @@ fn for_all_tests<F>(path: &Path, mut fun: F)
                 continue;
             }
 
-            if line == "//! ```" && test.len() > 0 {
+            if line == "//! ```" && !test.is_empty() {
                 let name = format!("{}_{}",
                                    path.file_stem().unwrap().to_string_lossy(),
                                    lineno); // XXX: nicer to point to the top
diff --git a/ipc/src/assuan/mod.rs b/ipc/src/assuan/mod.rs
index a3276210..6bbab37f 100644
--- a/ipc/src/assuan/mod.rs
+++ b/ipc/src/assuan/mod.rs
@@ -163,7 +163,7 @@ impl Client {
         let mut data = data.as_ref();
         let mut request = Vec::with_capacity(data.len());
         while ! data.is_empty() {
-            if request.len() > 0 {
+            if !request.is_empty() {
                 request.push(0x0a);
             }
             write!(&mut request, "D ").unwrap();
diff --git a/ipc/src/gnupg.rs b/ipc/src/gnupg.rs
index 1492345c..1d6b49bf 100644
--- a/ipc/src/gnupg.rs
+++ b/ipc/src/gnupg.rs
@@ -179,7 +179,7 @@ impl Context {
         if output.status.success() {
             let mut result = Vec::new();
             for mut line in output.stdout.split(nl) {
-                if line.len() == 0 {
+                if line.is_empty() {
                     // EOF.
                     break;
                 }
diff --git a/ipc/src/sexp.rs b/ipc/src/sexp.rs
index 771eee18..3d25862d 100644
--- a/ipc/src/sexp.rs
+++ b/ipc/src/sexp.rs
@@ -97,11 +97,11 @@ impl Sexp {
                     }
 
                     // Skip non-zero bytes.
-                    while s.len() > 0 && s[0] > 0 {
+                    while !s.is_empty() && s[0] > 0 {
                         s = &s[1..];
                     }
 
-                    if s.len() == 0 {
+                    if s.is_empty() {
                         return Err(Error::MalformedMPI(
                             "Invalid DEK encoding, no zero found".into())
                                    .into());
diff --git a/net/src/wkd.rs b/net/src/wkd.rs
index cc14613c..50f32206 100644
--- a/net/src/wkd.rs
+++ b/net/src/wkd.rs
@@ -364,7 +364,7 @@ pub fn insert<P, S, V>(base_path: P, domain: S, variant: V,
     }).collect::<Vec<_>>();
 
     // Any?
-    if addresses.len() == 0 {
+    if addresses.is_empty() {
         return Err(openpgp::Error::InvalidArgument(
             format!("Key {} does not have a UserID in {}", cert, domain)
         ).into());
diff --git a/openpgp-ffi/tests/c-tests.rs b/openpgp-ffi/tests/c-tests.rs
index 33a52261..ee906b0e 100644
--- a/openpgp-ffi/tests/c-tests.rs
+++ b/openpgp-ffi/tests/c-tests.rs
@@ -162,7 +162,7 @@ fn for_all_tests<F>(path: &Path, mut fun: F)
             }
 
             if let Some(name) = exported_function_name(&line) {
-                if test.len() > 0 {
+                if !test.is_empty() {
                     fun(path, test_starts_at, &name, replace(&mut test, vec![]),
                         run)?;
                     test.clear();
@@ -174,7 +174,7 @@ fn for_all_tests<F>(path: &Path, mut fun: F)
                 continue;
             }
 
-            if line == "//! ```" && test.len() > 0 {
+            if line == "//! ```" && !test.is_empty() {
                 let name = format!("{}_{}",
                                    path.file_stem().unwrap().to_string_lossy(),
                                    lineno); // XXX: nicer to point to the top
diff --git a/openpgp/examples/statistics.rs b/openpgp/examples/statistics.rs
index 502af558..fc262ee8 100644
--- a/openpgp/examples/statistics.rs
+++ b/openpgp/examples/statistics.rs
@@ -427,7 +427,7 @@ fn main() -> openpgp::Result<()> {
         }
     }
 
-    if key_flags.len() > 0 {
+    if !key_flags.is_empty() {
         println!();
         println!("# KeyFlags statistics");
         println!();
@@ -443,7 +443,7 @@ fn main() -> openpgp::Result<()> {
         }
     }
 
-    if p_sym.len() > 0 {
+    if !p_sym.is_empty() {
         println!();
         println!("# PreferredSymmetricAlgorithms statistics");
         println!();
@@ -462,7 +462,7 @@ fn main() -> openpgp::Result<()> {
         }
     }
 
-    if p_hashes.len() > 0 {
+    if !p_hashes.is_empty() {
         println!();
         println!("# PreferredHashlgorithms statistics");
         println!();
@@ -482,7 +482,7 @@ fn main() -> openpgp::Result<()> {
         }
     }
 
-    if p_comp.len() > 0 {
+    if !p_comp.is_empty() {
         println!();
         println!("# PreferredCompressionAlgorithms statistics");
         println!();
@@ -502,7 +502,7 @@ fn main() -> openpgp::Result<()> {
         }
     }
 
-    if p_aead.len() > 0 {
+    if !p_aead.is_empty() {
         println!();
         println!("# PreferredAEADAlgorithms statistics");
         println!();
diff --git a/openpgp/src/armor.rs b/openpgp/src/armor.rs
index c5d53b83..6a5eb9bb 100644
--- a/openpgp/src/armor.rs
+++ b/openpgp/src/armor.rs
@@ -370,7 +370,7 @@ impl<W: Write> Writer<W> {
         self.finalize_headers()?;
 
         // Write any stashed bytes and pad.
-        if self.stash.len() > 0 {
+        if !self.stash.is_empty() {
             self.sink.write_all(base64::encode_config(
                 &self.stash, base64::STANDARD).as_bytes())?;
             self.column += 4;
@@ -430,9 +430,9 @@ impl<W: Write> Write for Writer<W> {
         // and encode it.  If writing out the stash fails below, we
         // might end up with a stash of size 3.
         assert!(self.stash.len() <= 3);
-        if self.stash.len() > 0 {
+        if !self.stash.is_empty() {
             while self.stash.len() < 3 {
-                if input.len() == 0 {
+                if input.is_empty() {
                     /* We exhausted the input.  Return now, any
                      * stashed bytes are encoded when finalizing the
                      * writer.  */
@@ -470,7 +470,7 @@ impl<W: Write> Write for Writer<W> {
         let encoded = base64::encode_config(input, base64::STANDARD_NO_PAD);
         written += input.len();
         let mut enc = encoded.as_bytes();
-        while enc.len() > 0 {
+        while !enc.is_empty() {
             let n = cmp::min(LINE_LENGTH - self.column, enc.len());
             self.sink
                 .write_all(&enc[..n])?;
@@ -1086,7 +1086,7 @@ impl<'a> Reader<'a> {
             /* Process headers.  */
             let key_value = line.splitn(2, ": ").collect::<Vec<&str>>();
             if key_value.len() == 1 {
-                if line.trim_start().len() == 0 {
+                if line.trim_start().is_empty() {
                     // Empty line.
                     break;
                 } else if lines == 1 {
@@ -1143,7 +1143,7 @@ fn common_prefix<A: AsRef<[u8]>, B: AsRef<[u8]>>(a: A, b: B) -> usize {
 
 impl<'a> Reader<'a> {
     fn read_armored_data(&mut self, buf: &mut [u8]) -> Result<usize> {
-        let (consumed, decoded) = if self.decode_buffer.len() > 0 {
+        let (consumed, decoded) = if !self.decode_buffer.is_empty() {
             // We have something buffered, use that.
 
             let amount = cmp::min(buf.len(), self.decode_buffer.len());
@@ -1250,7 +1250,7 @@ impl<'a> Reader<'a> {
             /* Look for CRC.  The CRC is optional.  */
             let consumed = {
                 // Skip whitespace.
-                while self.source.data(1)?.len() > 0
+                while !self.source.data(1)?.is_empty()
                     && self.source.buffer()[0].is_ascii_whitespace()
                 {
                     self.source.consume(1);
@@ -1294,7 +1294,7 @@ impl<'a> Reader<'a> {
             // Look for a footer.
             let consumed = {
                 // Skip whitespace.
-                while self.source.data(1)?.len() > 0
+                while !self.source.data(1)?.is_empty()
                     && self.source.buffer()[0].is_ascii_whitespace()
                 {
                     self.source.consume(1);
@@ -1384,7 +1384,7 @@ impl<'a> Reader<'a> {
                     loop {
                         let prefixed_line = self.source.read_to(b'\n')?;
 
-                        if prefixed_line.len() == 0 {
+                        if prefixed_line.is_empty() {
                             // Truncated?
                             break;
                         }
@@ -1502,7 +1502,7 @@ impl<'a> Reader<'a> {
             self.initialize()?;
         }
 
-        if buf.len() == 0 {
+        if buf.is_empty() {
             // Short-circuit here.  Otherwise, we copy 0 bytes into
             // the buffer, which means we decoded 0 bytes, and we
             // wrongfully assume that we reached the end of the
diff --git a/openpgp/src/armor/base64_utils.rs b/openpgp/src/armor/base64_utils.rs
index 9e7fe500..aac7ae2a 100644
--- a/openpgp/src/armor/ba