chore: fix inconsistent terminology

I noticed a handful of places where `v0.1.x` refers to `Subscriber`s as
 "collectors". This probably happened because we backported some commits
 from master and forgot to change every instance of "collector" back to
 "subscriber".

 This commit fixes that. Whoops.

Signed-off-by: Eliza Weisman <eliza@buoyant.io>

examples/examples/fmt-multiple-writers.rs

@@ -17,7 +17,7 @@ fn main() {
         .with(EnvFilter::from_default_env().add_directive(tracing::Level::TRACE.into()))
         .with(fmt::Layer::new().with_writer(io::stdout))
         .with(fmt::Layer::new().with_writer(non_blocking));
-    tracing::subscriber::set_global_default(subscriber).expect("Unable to set a global collector");
+    tracing::subscriber::set_global_default(subscriber).expect("Unable to set a global subscriber");
 
     let number_of_yaks = 3;
     // this creates a new event, outside of any spans.

examples/examples/fmt-pretty.rs

@@ -8,7 +8,7 @@ fn main() {
         .with_thread_names(true)
         // enable everything
         .with_max_level(tracing::Level::TRACE)
-        // sets this to be the default, global collector for this application.
+        // sets this to be the default, global subscriber for this application.
         .init();
 
     let number_of_yaks = 3;

examples/examples/fmt.rs

@@ -6,7 +6,7 @@ fn main() {
     tracing_subscriber::fmt()
         // enable everything
         .with_max_level(tracing::Level::TRACE)
-        // sets this to be the default, global collector for this application.
+        // sets this to be the default, global subscriber for this application.
         .init();
 
     let number_of_yaks = 3;

tracing-opentelemetry/src/span_ext.rs

@@ -138,9 +138,9 @@ impl OpenTelemetrySpanExt for tracing::Span {
         if cx.is_valid() {
             let mut cx = Some(cx);
             let mut att = Some(attributes);
-            self.with_subscriber(move |(id, collector)| {
-                if let Some(get_context) = collector.downcast_ref::<WithContext>() {
-                    get_context.with_context(collector, id, move |builder, _tracer| {
+            self.with_subscriber(move |(id, subscriber)| {
+                if let Some(get_context) = subscriber.downcast_ref::<WithContext>() {
+                    get_context.with_context(subscriber, id, move |builder, _tracer| {
                         if let Some(cx) = cx.take() {
                             let attr = att.take().unwrap_or_default();
                             let follows_link = opentelemetry::trace::Link::new(cx, attr);

tracing-subscriber/src/filter/env/mod.rs

@@ -261,7 +261,7 @@ impl EnvFilter {
             #[cfg(feature = "ansi_term")]
             use ansi_term::{Color, Style};
             // NOTE: We can't use a configured `MakeWriter` because the EnvFilter
-            // has no knowledge of any underlying subscriber or collector, which
+            // has no knowledge of any underlying subscriber or subscriber, which
             // may or may not use a `MakeWriter`.
             let warn = |msg: &str| {
                 #[cfg(not(feature = "ansi_term"))]

tracing-subscriber/src/fmt/mod.rs

@@ -27,7 +27,7 @@
 //!
 //! ## Filtering Events with Environment Variables
 //!
-//! The default collector installed by `init` enables you to filter events
+//! The default subscriber installed by `init` enables you to filter events
 //! at runtime using environment variables (using the [`EnvFilter`]).
 //!
 //! The filter syntax is a superset of the [`env_logger`] syntax.
@@ -52,7 +52,7 @@
 //! You can create one by calling:
 //!
 //! ```rust
-//! let collector = tracing_subscriber::fmt()
+//! let subscriber = tracing_subscriber::fmt()
 //!     // ... add configuration
 //!     .finish();
 //! ```
@@ -336,7 +336,7 @@ pub struct SubscriberBuilder<
 ///     .with_target(false)
 ///     .with_timer(tracing_subscriber::fmt::time::uptime())
 ///     .with_level(true)
-///     // Set the collector as the default.
+///     // Set the subscriber as the default.
 ///     .init();
 /// ```
 ///
@@ -347,11 +347,11 @@ pub struct SubscriberBuilder<
 ///
 /// fn init_subscriber() -> Result<(), Box<dyn Error + Send + Sync + 'static>> {
 ///     tracing_subscriber::fmt()
-///         // Configure the collector to emit logs in JSON format.
+///         // Configure the subscriber to emit logs in JSON format.
 ///         .json()
-///         // Configure the collector to flatten event fields in the output JSON objects.
+///         // Configure the subscriber to flatten event fields in the output JSON objects.
 ///         .flatten_event(true)
-///         // Set the collector as the default, returning an error if this fails.
+///         // Set the subscriber as the default, returning an error if this fails.
 ///         .try_init()?;
 ///
 ///     Ok(())

tracing/tests/span.rs

@@ -461,7 +461,7 @@ fn move_field_out_of_struct() {
 #[cfg_attr(target_arch = "wasm32", wasm_bindgen_test::wasm_bindgen_test)]
 #[test]
 fn float_values() {
-    let (collector, handle) = collector::mock()
+    let (subscriber, handle) = subscriber::mock()
         .new_span(
             span::mock().named("foo").with_field(
                 field::mock("x")
@@ -472,7 +472,7 @@ fn float_values() {
         )
         .run_with_handle();
 
-    with_default(collector, || {
+    with_default(subscriber, || {
         let foo = span!(Level::TRACE, "foo", x = 3.234, y = -1.223);
         foo.in_scope(|| {});
     });