core: replace color-backtrace with color-eyre

This begins a general migration to `eyre` for error handling:

https://github.com/yaahc/color-eyre

core/Cargo.toml

@@ -21,7 +21,7 @@ arc-swap = { version = "1", optional = true }
 backtrace = "0.3"
 canonical-path = "2"
 chrono = { version = "0.4", optional = true, features = ["serde"] }
-color-backtrace = { version = "0.5", optional = true, default-features = false }
+color-eyre = { version = "0.5", optional = true, default-features = false }
 fs-err = "2"
 gumdrop = { version = "0.7", optional = true }
 once_cell = "1.4"
@@ -65,6 +65,6 @@ config = [
 trace = ["tracing", "tracing-log", "tracing-subscriber"]
 options = ["gumdrop"]
 secrets = ["secrecy"]
-terminal = ["color-backtrace", "termcolor"]
+terminal = ["color-eyre", "termcolor"]
 testing = ["regex", "wait-timeout"]
 time = ["chrono"]

core/src/terminal/component.rs

@@ -1,30 +1,24 @@
 //! Terminal component
 
 use crate::Component;
-use std::fmt;
 use termcolor::ColorChoice;
 
 /// Abscissa terminal subsystem component
-#[derive(Component)]
+#[derive(Component, Debug)]
 #[component(core)]
 pub struct Terminal {}
 
 impl Terminal {
-    /// Create a new `TerminalComponent` with the given `ColorChoice`
+    /// Create a new [`Terminal`] component with the given [`ColorChoice`]
     pub fn new(color_choice: ColorChoice) -> Terminal {
         // TODO(tarcieri): handle terminal reinit (without panicking)
         super::init(color_choice);
 
         if color_choice != ColorChoice::Never {
-            color_backtrace::install();
+            // TODO(tarcieri): avoid panicking here
+            color_eyre::install().expect("couldn't install color-eyre");
         }
 
         Self {}
     }
 }
-
-impl fmt::Debug for Terminal {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        write!(f, "TerminalComponent {{ stdout, stderr }}")
-    }
-}