Fix clippy lints (#510)

Author: joshka

clippy.toml

@@ -1 +1,2 @@
 too-many-lines-threshold = 150
+ignore-interior-mutability = ["metrics::key::Key"]

metrics-exporter-prometheus/src/distribution.rs

@@ -33,7 +33,10 @@ pub enum Distribution {
 
 impl Distribution {
     /// Creates a histogram distribution.
-    #[warn(clippy::missing_panics_doc)]
+    ///
+    /// # Panics
+    ///
+    /// Panics if `buckets` is empty.
     pub fn new_histogram(buckets: &[f64]) -> Distribution {
         let hist = Histogram::new(buckets).expect("buckets should never be empty");
         Distribution::Histogram(hist)
@@ -299,8 +302,11 @@ mod tests {
         let snapshot = summary.snapshot(clock.now());
 
         assert_eq!(0, snapshot.count());
-        assert_eq!(f64::INFINITY, snapshot.min());
-        assert_eq!(f64::NEG_INFINITY, snapshot.max());
+        #[allow(clippy::float_cmp)]
+        {
+            assert_eq!(f64::INFINITY, snapshot.min());
+            assert_eq!(f64::NEG_INFINITY, snapshot.max());
+        }
         assert_eq!(None, snapshot.quantile(0.5));
     }
 
@@ -318,8 +324,11 @@ mod tests {
 
         let snapshot = summary.snapshot(clock.now());
 
-        assert_eq!(42.0, snapshot.min());
-        assert_eq!(42.0, snapshot.max());
+        #[allow(clippy::float_cmp)]
+        {
+            assert_eq!(42.0, snapshot.min());
+            assert_eq!(42.0, snapshot.max());
+        }
         // 42 +/- (42 * 0.0001)
         assert!(Some(41.9958) < snapshot.quantile(0.5));
         assert!(Some(42.0042) > snapshot.quantile(0.5));

metrics-exporter-prometheus/src/exporter/builder.rs

@@ -560,8 +560,7 @@ mod tests {
         gauge1.set(-3.14);
         let rendered = handle.render();
         let expected_gauge = format!(
-            "{}# TYPE basic_gauge gauge\nbasic_gauge{{wutang=\"forever\"}} -3.14\n\n",
-            expected_counter
+            "{expected_counter}# TYPE basic_gauge gauge\nbasic_gauge{{wutang=\"forever\"}} -3.14\n\n",
         );
 
         assert_eq!(rendered, expected_gauge);
@@ -579,7 +578,7 @@ mod tests {
             "basic_histogram_count 1\n",
             "\n"
         );
-        let expected_histogram = format!("{}{}", expected_gauge, histogram_data);
+        let expected_histogram = format!("{expected_gauge}{histogram_data}");
 
         assert_eq!(rendered, expected_histogram);
     }

metrics-exporter-prometheus/src/exporter/http_listener.rs

@@ -59,11 +59,11 @@ impl HttpListeningExporter {
                     continue;
                 }
             };
-            self.process_tcp_stream(stream).await;
+            self.process_tcp_stream(stream);
         }
     }
 
-    async fn process_tcp_stream(&self, stream: TcpStream) {
+    fn process_tcp_stream(&self, stream: TcpStream) {
         let is_allowed = self.check_tcp_allowed(&stream);
         let handle = self.handle.clone();
         let service = service_fn(move |req: Request<body::Incoming>| {
@@ -107,12 +107,12 @@ impl HttpListeningExporter {
                     continue;
                 }
             };
-            self.process_uds_stream(stream).await;
+            self.process_uds_stream(stream);
         }
     }
 
     #[cfg(feature = "uds-listener")]
-    async fn process_uds_stream(&self, stream: UnixStream) {
+    fn process_uds_stream(&self, stream: UnixStream) {
         let handle = self.handle.clone();
         let service = service_fn(move |req: Request<body::Incoming>| {
             let handle = handle.clone();

metrics-exporter-prometheus/src/exporter/push_gateway.rs

@@ -94,7 +94,7 @@ fn basic_auth(username: &str, password: Option<&str>) -> HeaderValue {
     header
 }
 
-#[cfg(all(test))]
+#[cfg(test)]
 mod tests {
     use super::basic_auth;
 

metrics-exporter-prometheus/src/formatting.rs

@@ -110,35 +110,37 @@ pub fn write_metric_line<T, T2>(
 /// [data model]: https://prometheus.io/docs/concepts/data_model/#metric-names-and-labels
 pub fn sanitize_metric_name(name: &str) -> String {
     // The first character must be [a-zA-Z_:], and all subsequent characters must be [a-zA-Z0-9_:].
-    let mut out = String::with_capacity(name.len());
-    let mut is_invalid: fn(char) -> bool = invalid_metric_name_start_character;
-    for c in name.chars() {
-        if is_invalid(c) {
-            out.push('_');
-        } else {
-            out.push(c);
-        }
-        is_invalid = invalid_metric_name_character;
-    }
-    out
+    name.chars()
+        .enumerate()
+        .map(|(i, c)| {
+            if i == 0 && valid_metric_name_start_character(c)
+                || i != 0 && valid_metric_name_character(c)
+            {
+                c
+            } else {
+                '_'
+            }
+        })
+        .collect()
 }
 
 /// Sanitizes a label key to be valid under the Prometheus [data model].
 ///
 /// [data model]: https://prometheus.io/docs/concepts/data_model/#metric-names-and-labels
 pub fn sanitize_label_key(key: &str) -> String {
     // The first character must be [a-zA-Z_], and all subsequent characters must be [a-zA-Z0-9_].
-    let mut out = String::with_capacity(key.len());
-    let mut is_invalid: fn(char) -> bool = invalid_label_key_start_character;
-    for c in key.chars() {
-        if is_invalid(c) {
-            out.push('_');
-        } else {
-            out.push(c);
-        }
-        is_invalid = invalid_label_key_character;
-    }
-    out
+    key.chars()
+        .enumerate()
+        .map(|(i, c)| {
+            if i == 0 && valid_label_key_start_character(c)
+                || i != 0 && valid_label_key_character(c)
+            {
+                c
+            } else {
+                '_'
+            }
+        })
+        .collect()
 }
 
 /// Sanitizes a label value to be valid under the Prometheus [data model].
@@ -209,35 +211,35 @@ fn sanitize_label_value_or_description(value: &str, is_desc: bool) -> String {
 }
 
 #[inline]
-fn invalid_metric_name_start_character(c: char) -> bool {
+fn valid_metric_name_start_character(c: char) -> bool {
     // Essentially, needs to match the regex pattern of [a-zA-Z_:].
-    !(c.is_ascii_alphabetic() || c == '_' || c == ':')
+    c.is_ascii_alphabetic() || c == '_' || c == ':'
 }
 
 #[inline]
-fn invalid_metric_name_character(c: char) -> bool {
+fn valid_metric_name_character(c: char) -> bool {
     // Essentially, needs to match the regex pattern of [a-zA-Z0-9_:].
-    !(c.is_ascii_alphanumeric() || c == '_' || c == ':')
+    c.is_ascii_alphanumeric() || c == '_' || c == ':'
 }
 
 #[inline]
-fn invalid_label_key_start_character(c: char) -> bool {
+fn valid_label_key_start_character(c: char) -> bool {
     // Essentially, needs to match the regex pattern of [a-zA-Z_].
-    !(c.is_ascii_alphabetic() || c == '_')
+    c.is_ascii_alphabetic() || c == '_'
 }
 
 #[inline]
-fn invalid_label_key_character(c: char) -> bool {
+fn valid_label_key_character(c: char) -> bool {
     // Essentially, needs to match the regex pattern of [a-zA-Z0-9_].
-    !(c.is_ascii_alphanumeric() || c == '_')
+    c.is_ascii_alphanumeric() || c == '_'
 }
 
 #[cfg(test)]
 mod tests {
     use crate::formatting::{
-        invalid_label_key_character, invalid_label_key_start_character,
-        invalid_metric_name_character, invalid_metric_name_start_character, sanitize_description,
-        sanitize_label_key, sanitize_label_value, sanitize_metric_name,
+        sanitize_description, sanitize_label_key, sanitize_label_value, sanitize_metric_name,
+        valid_label_key_character, valid_label_key_start_character, valid_metric_name_character,
+        valid_metric_name_start_character,
     };
     use proptest::prelude::*;
 
@@ -321,11 +323,11 @@ mod tests {
             let as_chars = result.chars().collect::<Vec<_>>();
 
             if let Some(c) = as_chars.first() {
-                assert_eq!(false, invalid_metric_name_start_character(*c),
+                assert!(valid_metric_name_start_character(*c),
                     "first character of metric name was not valid");
             }
 
-            assert!(!as_chars.iter().any(|c| invalid_metric_name_character(*c)),
+            assert!(as_chars.iter().all(|c| valid_metric_name_character(*c)),
                 "invalid character in metric name");
         }
 
@@ -335,7 +337,7 @@ mod tests {
             let as_chars = result.chars().collect::<Vec<_>>();
 
             if let Some(c) = as_chars.first() {
-                assert_eq!(false, invalid_label_key_start_character(*c),
+                assert!(valid_label_key_start_character(*c),
                     "first character of label key was not valid");
             }
 
@@ -353,7 +355,7 @@ mod tests {
                 }
             }*/
 
-            assert!(!as_chars.iter().any(|c| invalid_label_key_character(*c)),
+            assert!(as_chars.iter().all(|c| valid_label_key_character(*c)),
                 "invalid character in label key");
         }
 
@@ -369,7 +371,7 @@ mod tests {
             let as_chars = delayered_backslashes.chars().collect::<Vec<_>>();
 
             // If the first character is a double quote, then we messed up.
-            assert!(as_chars.first().map(|c| *c != '"').unwrap_or(true),
+            assert!(as_chars.first().map_or(true, |c| *c != '"'),
                 "first character cannot be a double quote: {}", result);
 
             // Now look for unescaped characters in the rest of the string, in a windowed fashion.

metrics-exporter-prometheus/tests/http_listener_integration_test.rs

@@ -36,7 +36,7 @@ mod http_listener_test {
             let labels = vec![Label::new("wutang", "forever")];
             let key = Key::from_parts("basic_gauge", labels);
             let gauge = recorder.register_gauge(&key, &METADATA);
-            gauge.set(-3.14);
+            gauge.set(-1.23);
 
             runtime.spawn(exporter); //async { exporter.await});
             tokio::time::sleep(Duration::from_millis(200)).await;
@@ -48,7 +48,7 @@ mod http_listener_test {
             let (status, body) = read_from(uri).await;
 
             assert_eq!(status, StatusCode::OK);
-            assert!(body.contains("basic_gauge{wutang=\"forever\"} -3.14"));
+            assert!(body.contains("basic_gauge{wutang=\"forever\"} -1.23"));
         });
     }
 

metrics-tracing-context/benches/layer.rs

@@ -12,9 +12,9 @@ fn layer_benchmark(c: &mut Criterion) {
     let mut group = c.benchmark_group("layer");
     group.bench_function("base case", |b| {
         let recorder = NoopRecorder;
-        static KEY_NAME: &'static str = "key";
+        static KEY_NAME: &str = "key";
         static KEY_LABELS: [Label; 1] = [Label::from_static_parts("foo", "bar")];
-        static KEY_DATA: Key = Key::from_static_parts(&KEY_NAME, &KEY_LABELS);
+        static KEY_DATA: Key = Key::from_static_parts(KEY_NAME, &KEY_LABELS);
         static METADATA: metrics::Metadata =
             metrics::Metadata::new(module_path!(), metrics::Level::INFO, Some(module_path!()));
 
@@ -32,9 +32,9 @@ fn layer_benchmark(c: &mut Criterion) {
             let _guard = span.enter();
 
             let recorder = NoopRecorder;
-            static KEY_NAME: &'static str = "key";
+            static KEY_NAME: &str = "key";
             static KEY_LABELS: [Label; 1] = [Label::from_static_parts("foo", "bar")];
-            static KEY_DATA: Key = Key::from_static_parts(&KEY_NAME, &KEY_LABELS);
+            static KEY_DATA: Key = Key::from_static_parts(KEY_NAME, &KEY_LABELS);
             static METADATA: metrics::Metadata =
                 metrics::Metadata::new(module_path!(), metrics::Level::INFO, Some(module_path!()));
 
@@ -53,9 +53,9 @@ fn layer_benchmark(c: &mut Criterion) {
             let _guard = span.enter();
 
             let recorder = NoopRecorder;
-            static KEY_NAME: &'static str = "key";
+            static KEY_NAME: &str = "key";
             static KEY_LABELS: [Label; 1] = [Label::from_static_parts("foo", "bar")];
-            static KEY_DATA: Key = Key::from_static_parts(&KEY_NAME, &KEY_LABELS);
+            static KEY_DATA: Key = Key::from_static_parts(KEY_NAME, &KEY_LABELS);
             static METADATA: metrics::Metadata =
                 metrics::Metadata::new(module_path!(), metrics::Level::INFO, Some(module_path!()));
 
@@ -75,9 +75,9 @@ fn layer_benchmark(c: &mut Criterion) {
 
             let tracing_layer = TracingContextLayer::all();
             let recorder = tracing_layer.layer(NoopRecorder);
-            static KEY_NAME: &'static str = "key";
+            static KEY_NAME: &str = "key";
             static KEY_LABELS: [Label; 1] = [Label::from_static_parts("foo", "bar")];
-            static KEY_DATA: Key = Key::from_static_parts(&KEY_NAME, &KEY_LABELS);
+            static KEY_DATA: Key = Key::from_static_parts(KEY_NAME, &KEY_LABELS);
             static METADATA: metrics::Metadata =
                 metrics::Metadata::new(module_path!(), metrics::Level::INFO, Some(module_path!()));
 
@@ -97,9 +97,9 @@ fn layer_benchmark(c: &mut Criterion) {
 
             let tracing_layer = TracingContextLayer::all();
             let recorder = tracing_layer.layer(NoopRecorder);
-            static KEY_NAME: &'static str = "key";
+            static KEY_NAME: &str = "key";
             static KEY_LABELS: [Label; 1] = [Label::from_static_parts("foo", "bar")];
-            static KEY_DATA: Key = Key::from_static_parts(&KEY_NAME, &KEY_LABELS);
+            static KEY_DATA: Key = Key::from_static_parts(KEY_NAME, &KEY_LABELS);
             static METADATA: metrics::Metadata =
                 metrics::Metadata::new(module_path!(), metrics::Level::INFO, Some(module_path!()));
 

metrics-tracing-context/benches/visit.rs

@@ -140,7 +140,7 @@ struct DebugStruct {
 
 impl DebugStruct {
     pub fn new() -> DebugStruct {
-        DebugStruct { field1: format!("yeehaw!"), field2: 324242343243 }
+        DebugStruct { field1: "yeehaw!".to_string(), field2: 324242343243 }
     }
 }
 

metrics-tracing-context/src/tracing_integration.rs

@@ -97,6 +97,7 @@ impl AsRef<Map> for Labels {
 /// fields and allows them to be later on used as metrics labels.
 #[derive(Default)]
 pub struct MetricsLayer {
+    #[allow(clippy::type_complexity)]
     with_labels:
         Option<fn(&Dispatch, &Id, f: &mut dyn FnMut(&Labels) -> Option<Key>) -> Option<Key>>,
 }