Provide a library interface

Cargo.toml

@@ -18,20 +18,23 @@ name = "sp"
 path = "src/main.rs"
 
 [dependencies]
+anyhow = "1.0.20"
 bit-set = "0.5.1"
 clap = { version = "2.32.0", features = ["wrap_help"] }
-failure = "0.1.5"
 lazy_static = "1.3.0"
 lru-cache = "0.1.2"
 memmap = "0.7.0"
 regex = "1.1.5"
 scopeguard = "1.0.0"
 smallvec = "0.6.9"
 terminfo = "0.6"
-termwiz = "0.3.1"
+termwiz = "0.5"
 unicode-segmentation = "1.2.1"
 unicode-width = "0.1.5"
 vec_map = "0.8.1"
 
 [build-dependencies]
 clap = "2.32.0"
+
+[dev-dependencies]
+pipe = "0.2.0"

examples/streams_example.rs

@@ -0,0 +1,52 @@
+// Run this with: cargo run --example streams_example
+
+use pipe::pipe;
+use std::io::Write;
+use std::thread::{sleep, spawn};
+use std::time::Duration;
+use streampager::{Pager, Result};
+
+fn main() -> Result<()> {
+    let (out_read, mut out_write) = pipe();
+    let (err_read, mut err_write) = pipe();
+    let (prog_read, mut prog_write) = pipe();
+
+    spawn(move || {
+        for i in 1..=100 {
+            let _ = out_write.write_all(format!("this is line {}\n", i).as_bytes());
+            sleep(Duration::from_millis(450));
+        }
+        let _ = out_write.write_all(b"this is the end of output stream\n");
+    });
+
+    spawn(move || {
+        for i in 1..=10 {
+            let _ = err_write.write_all(format!("this is error line {}\n", i).as_bytes());
+            sleep(Duration::from_millis(4000));
+        }
+        let _ = err_write.write_all(b"this is the end of error stream\n");
+    });
+
+    spawn(move || {
+        let mut extra: &[u8] = b"";
+        for i in 1..=100 {
+            let _ = prog_write.write_all(format!("progress step {}\n", i).as_bytes());
+            let _ = prog_write.write_all(extra);
+            let _ = prog_write.write_all(b"\x0c");
+            if i == 40 {
+                extra = b"\x1b[32mprogress can have colors and multiple lines\n";
+            }
+            sleep(Duration::from_millis(120));
+        }
+    });
+
+    let mut pager = Pager::new_using_system_terminal()?;
+    pager
+        .add_output_stream(out_read, "output stream")?
+        .add_error_stream(err_read, "error stream")?
+        .set_progress_stream(prog_read);
+    pager.run()?;
+
+    println!("pager has exited");
+    Ok(())
+}

src/command.rs

@@ -1,7 +1,7 @@
 //! Commands
 //!
 //! Commands the user can invoke.
-use failure::Error;
+use anyhow::Error;
 
 use crate::display::Action;
 use crate::event::EventSender;

src/display.rs

@@ -1,5 +1,5 @@
 //! Manage the Display.
-use failure::Error;
+use anyhow::Error;
 use scopeguard::guard;
 use std::time::Duration;
 use termwiz::caps::Capabilities as TermCapabilities;
@@ -45,7 +45,7 @@ impl Capabilities {
 /// An action that affects the display.
 pub(crate) enum Action {
     /// Run a function.  The function may return a new action to run next.
-    Run(Box<FnMut(&mut Screen) -> Result<Option<Action>, Error>>),
+    Run(Box<dyn FnMut(&mut Screen) -> Result<Option<Action>, Error>>),
 
     /// Change the terminal.
     Change(Change),

src/event.rs

@@ -1,5 +1,5 @@
 //! Events.
-use failure::Error;
+use anyhow::Error;
 use std::sync::atomic::{AtomicBool, Ordering};
 use std::sync::mpsc;
 use std::sync::Arc;
@@ -97,7 +97,7 @@ impl EventStream {
     /// Get an event, either from the event stream or from the terminal.
     pub(crate) fn get(
         &self,
-        term: &mut Terminal,
+        term: &mut dyn Terminal,
         wait: Option<Duration>,
     ) -> Result<Option<Event>, Error> {
         // First, try to get an event from the queue.

src/file.rs

@@ -1,5 +1,5 @@
 //! Files.
-use failure::{Error, ResultExt};
+use anyhow::{Context, Error};
 use memmap::Mmap;
 use std::borrow::Cow;
 use std::cmp::min;
@@ -252,17 +252,27 @@ pub(crate) struct File {
 }
 
 impl File {
-    /// Load stdin.
-    pub(crate) fn new_stdin(
+    /// Load stream.
+    pub(crate) fn new_streamed(
         index: usize,
+        stream: impl Read + Send + 'static,
         title: &str,
         event_sender: EventSender,
     ) -> Result<File, Error> {
         let meta = Arc::new(FileMeta::new(index, title.to_string()));
-        let data = FileData::new_streamed(std::io::stdin(), meta.clone(), event_sender)?;
+        let data = FileData::new_streamed(stream, meta.clone(), event_sender)?;
         Ok(File { data, meta })
     }
 
+    /// Load stdin.
+    pub(crate) fn new_stdin(
+        index: usize,
+        title: &str,
+        event_sender: EventSender,
+    ) -> Result<File, Error> {
+        Self::new_streamed(index, std::io::stdin(), title, event_sender)
+    }
+
     /// Load an input fd
     pub(crate) fn new_fd(
         index: usize,