diff --git a/CHANGELOG.md b/CHANGELOG.md index 1d9638cb..63691c0e 100644 --- a/CHANGELOG.md +++ b/CHANGELOG.md @@ -9,13 +9,18 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0 ## [Unreleased] +### Fixed + +- `libherokubuildpack`: + - Fixed `log_header`, `log_error` and `log_warning` to correctly reset the ANSI colour styles at the end of each line. ([#890](https://github.com/heroku/libcnb.rs/pull/890)) + ## [0.26.0] - 2024-11-18 ### Changed - `libherokubuildpack`: - - Removed `buildpack_output` module. This functionality from ([#721](https://github.com/heroku/libcnb.rs/pull/721)) was experimental. The API was not stable and it is being removed. A similar API is available at [bullet_stream](https://crates.io/crates/bullet_stream). ([#852](https://github.com/heroku/libcnb.rs/pull/852) + - Removed `buildpack_output` module. This functionality from ([#721](https://github.com/heroku/libcnb.rs/pull/721)) was experimental. The API was not stable and it is being removed. A similar API is available at [bullet_stream](https://crates.io/crates/bullet_stream). ([#852](https://github.com/heroku/libcnb.rs/pull/852)) ## [0.25.0] - 2024-10-23 diff --git a/libherokubuildpack/src/log.rs b/libherokubuildpack/src/log.rs index 9e270e27..aa87d734 100644 --- a/libherokubuildpack/src/log.rs +++ b/libherokubuildpack/src/log.rs @@ -1,4 +1,4 @@ -use std::io::Write; +use std::io::{self, Write}; use termcolor::{Color, ColorChoice, ColorSpec, StandardStream, WriteColor}; /// # Panics @@ -10,16 +10,14 @@ use termcolor::{Color, ColorChoice, ColorSpec, StandardStream, WriteColor}; #[allow(clippy::unwrap_used)] pub fn log_error(header: impl AsRef, body: impl AsRef) { let mut stream = StandardStream::stderr(ColorChoice::Always); - stream - .set_color(ColorSpec::new().set_fg(Some(Color::Red)).set_bold(true)) - .unwrap(); - writeln!(&mut stream, "\n[Error: {}]", header.as_ref()).unwrap(); - stream.reset().unwrap(); + write_styled_message( + &mut stream, + format!("\n[Error: {}]", header.as_ref()), + ColorSpec::new().set_fg(Some(Color::Red)).set_bold(true), + ) + .unwrap(); - stream - .set_color(ColorSpec::new().set_fg(Some(Color::Red))) - .unwrap(); - writeln!(&mut stream, "{}", body.as_ref()).unwrap(); + write_styled_message(&mut stream, body, ColorSpec::new().set_fg(Some(Color::Red))).unwrap(); stream.flush().unwrap(); } @@ -32,16 +30,19 @@ pub fn log_error(header: impl AsRef, body: impl AsRef) { #[allow(clippy::unwrap_used)] pub fn log_warning(header: impl AsRef, body: impl AsRef) { let mut stream = StandardStream::stderr(ColorChoice::Always); - stream - .set_color(ColorSpec::new().set_fg(Some(Color::Yellow)).set_bold(true)) - .unwrap(); - writeln!(&mut stream, "\n[Warning: {}]", header.as_ref()).unwrap(); - stream.reset().unwrap(); + write_styled_message( + &mut stream, + format!("\n[Warning: {}]", header.as_ref()), + ColorSpec::new().set_fg(Some(Color::Yellow)).set_bold(true), + ) + .unwrap(); - stream - .set_color(ColorSpec::new().set_fg(Some(Color::Yellow))) - .unwrap(); - writeln!(&mut stream, "{}", body.as_ref()).unwrap(); + write_styled_message( + &mut stream, + body, + ColorSpec::new().set_fg(Some(Color::Yellow)), + ) + .unwrap(); stream.flush().unwrap(); } @@ -54,11 +55,12 @@ pub fn log_warning(header: impl AsRef, body: impl AsRef) { #[allow(clippy::unwrap_used)] pub fn log_header(title: impl AsRef) { let mut stream = StandardStream::stdout(ColorChoice::Always); - stream - .set_color(ColorSpec::new().set_fg(Some(Color::Magenta)).set_bold(true)) - .unwrap(); - writeln!(&mut stream, "\n[{}]", title.as_ref()).unwrap(); - stream.reset().unwrap(); + write_styled_message( + &mut stream, + format!("\n[{}]", title.as_ref()), + ColorSpec::new().set_fg(Some(Color::Magenta)).set_bold(true), + ) + .unwrap(); stream.flush().unwrap(); } @@ -72,3 +74,22 @@ pub fn log_info(message: impl AsRef) { println!("{}", message.as_ref()); std::io::stdout().flush().unwrap(); } + +// Styles each line of text separately, so that when buildpack output is streamed to the +// user (and prefixes like `remote:` added) the line colour doesn't leak into the prefixes. +fn write_styled_message( + stream: &mut StandardStream, + message: impl AsRef, + spec: &ColorSpec, +) -> io::Result<()> { + // Using `.split('\n')` rather than `.lines()` since the latter eats trailing newlines in + // the passed message, which would (a) prevent the caller from being able to add spacing at + // the end of their message and (b) differ from the `println!` / `writeln!` behaviour. + for line in message.as_ref().split('\n') { + stream.set_color(spec)?; + write!(stream, "{line}")?; + stream.reset()?; + writeln!(stream)?; + } + Ok(()) +}