Replace ansi feature with plugin (#138)

* Replace ansi feature with plugin

* Don't depend on ansi parser types in the core

Author: bugadani

.github/workflows/rust.yml

@@ -104,14 +104,14 @@ jobs:
         compare -metric AE ./assets/alignment-vertical.png ./target/screenshots/alignment-vertical.png result.png
         EG_SIMULATOR_DUMP="./target/screenshots/paragraph_spacing.png" cargo run --example paragraph_spacing
         compare -metric AE ./assets/paragraph_spacing.png ./target/screenshots/paragraph_spacing.png result.png
+        EG_SIMULATOR_DUMP="./target/screenshots/plugin-ansi.png" cargo run --example plugin-ansi
+        compare -metric AE ./assets/plugin-ansi.png ./target/screenshots/plugin-ansi.png result.png
         EG_SIMULATOR_DUMP="./target/screenshots/plugin-tail.png" cargo run --example plugin-tail
         compare -metric AE ./assets/plugin-tail.png ./target/screenshots/plugin-tail.png result.png
         EG_SIMULATOR_DUMP="./target/screenshots/special-characters.png" cargo run --example special-characters
         compare -metric AE ./assets/special-characters.png ./target/screenshots/special-characters.png result.png
         EG_SIMULATOR_DUMP="./target/screenshots/special-characters-tabs.png" cargo run --example special-characters-tabs
         compare -metric AE ./assets/special-characters-tabs.png ./target/screenshots/special-characters-tabs.png result.png
-        EG_SIMULATOR_DUMP="./target/screenshots/styles-ansi.png" cargo run --example styles-ansi
-        compare -metric AE ./assets/styles-ansi.png ./target/screenshots/styles-ansi.png result.png
         EG_SIMULATOR_DUMP="./target/screenshots/styles-plugin.png" cargo run --example styles-plugin --features=plugin
         compare -metric AE ./assets/styles-plugin.png ./target/screenshots/styles-plugin.png result.png
         EG_SIMULATOR_DUMP="./target/screenshots/styles-static.png" cargo run --example styles-static

CHANGELOG.md

@@ -12,6 +12,8 @@ Unreleased
  * [#137] Allow using multiple plugins.
  * [#136] `Cursor` is now public.
  * [#136] Added `TextBox::take_plugins()`.
+ * [#138] `Ansi` plugin to parse ANSI escape sequences.
+ * [#138] `Token::MoveCursor` and `Token::ChangeTextStyle`
 
 ## Changed:
 
@@ -26,13 +28,15 @@ Unreleased
 ## Removed:
 
  * [#134] `Scrolling` vertical alignment
+ * [#138] `ansi` feature flag
 
 [#133]: https://github.com/embedded-graphics/embedded-text/pull/133
 [#134]: https://github.com/embedded-graphics/embedded-text/pull/134
 [#135]: https://github.com/embedded-graphics/embedded-text/pull/135
 [#136]: https://github.com/embedded-graphics/embedded-text/pull/136
 [#137]: https://github.com/embedded-graphics/embedded-text/pull/137
 [#140]: https://github.com/embedded-graphics/embedded-text/pull/140
+[#138]: https://github.com/embedded-graphics/embedded-text/pull/138
 
 0.5.0-beta.2 (2021-07-10)
 ==========================

Cargo.toml

@@ -15,9 +15,8 @@ exclude = [
 ]
 
 [features]
-ansi = ["ansi-parser", "as-slice"]
 plugin = []
-default = ["ansi"]
+default = []
 
 [[example]]
 name = "interactive-editor"
@@ -34,8 +33,8 @@ required-features = ["plugin"]
 [dependencies]
 az = "1.1"
 embedded-graphics = "0.7.0"
-ansi-parser = { version = "0.8.0", default-features = false, optional = true }
-as-slice = { version = "0.1.4", optional = true }
+ansi-parser = { version = "0.8.0", default-features = false }
+as-slice = { version = "0.1.4" }
 object-chain = "0.1"
 
 [dev-dependencies]

README.md

@@ -23,7 +23,7 @@ This crate provides a configurable `TextBox` to render multiline text inside a b
  - carriage return (`\r`)
  - tab (`\t`) with configurable tab size
 
-`TextBox` also supports text coloring using [ANSI escape codes](https://en.wikipedia.org/wiki/ANSI_escape_code).
+`TextBox` also supports text coloring using [ANSI escape codes](https://en.wikipedia.org/wiki/ANSI_escape_code) via the `Ansi` plugin.
 
 ### Example
 
@@ -32,7 +32,7 @@ The examples are based on [the embedded-graphics simulator]. The simulator is bu
 
 ![embedded-text example](https://raw.githubusercontent.com/embedded-graphics/embedded-text/master/assets/paragraph_spacing.png)
 
-![embedded-text example with colored text](https://raw.githubusercontent.com/embedded-graphics/embedded-text/master/assets/styles-ansi.png)
+![embedded-text example with colored text](https://raw.githubusercontent.com/embedded-graphics/embedded-text/master/assets/plugin-ansi.png)
 
 ```rust
 use embedded_graphics::{
@@ -93,7 +93,6 @@ fn main() {
 
 ## Cargo features
 
- * `ansi`: enables ANSI sequence support. This feature is enabled by default.
  * `plugin` (*experimental*): allows the user to implement plugins.
 
 [embedded-graphics]: https://github.com/embedded-graphics/embedded-graphics/

assets/styles-ansi.png renamed to assets/plugin-ansi.png

@@ -11,7 +11,7 @@ use embedded_graphics::{
     text::LineHeight,
 };
 use embedded_graphics_simulator::{OutputSettingsBuilder, SimulatorDisplay, Window};
-use embedded_text::{style::TextBoxStyleBuilder, TextBox};
+use embedded_text::{plugin::ansi::Ansi, style::TextBoxStyleBuilder, TextBox};
 use std::convert::Infallible;
 
 fn main() -> Result<(), Infallible> {
@@ -52,6 +52,7 @@ fn main() -> Result<(), Infallible> {
         character_style,
         textbox_style,
     )
+    .add_plugin(Ansi::new())
     .draw(&mut display)?;
 
     // Set up the window and show the display's contents.

examples/styles-ansi.rs renamed to examples/plugin-ansi.rs

@@ -13,6 +13,7 @@ use embedded_graphics_simulator::{
     BinaryColorTheme, OutputSettingsBuilder, SimulatorDisplay, Window,
 };
 use embedded_text::{
+    plugin::ansi::Ansi,
     style::{HeightMode, TabSize, TextBoxStyleBuilder},
     TextBox,
 };
@@ -46,7 +47,8 @@ fn main() {
     let bounds = Rectangle::new(Point::zero(), Size::new(180, 0));
 
     // Create the text box and apply styling options.
-    let text_box = TextBox::with_textbox_style(text, bounds, character_style, textbox_style);
+    let text_box = TextBox::with_textbox_style(text, bounds, character_style, textbox_style)
+        .add_plugin(Ansi::new());
 
     // Create a simulated display with the dimensions of the text box.
     let mut display = SimulatorDisplay::new(text_box.bounding_box().size);

examples/special-characters-tabs.rs

@@ -91,7 +91,6 @@
 //!
 //! ## Cargo features
 //!
-//! * `ansi`: enables ANSI sequence support. This feature is enabled by default.
 //! * `plugin` (*experimental*): allows the user to implement plugins.
 //!
 //! [embedded-graphics]: https://github.com/embedded-graphics/embedded-graphics/

src/lib.rs

@@ -16,8 +16,6 @@
 //!     tokens
 //! );
 //! ```
-#[cfg(feature = "ansi")]
-use ansi_parser::AnsiSequence;
 use core::{marker::PhantomData, str::Chars};
 use embedded_graphics::{prelude::PixelColor, text::DecorationColor};
 
@@ -70,9 +68,13 @@ where
     /// Change of text style.
     ChangeTextStyle(ChangeTextStyle<C>),
 
-    /// An ANSI escape sequence
-    #[cfg(feature = "ansi")]
-    EscapeSequence(AnsiSequence),
+    /// Move the cursor by a number of characters.
+    MoveCursor {
+        /// Number of characters to move.
+        chars: i32,
+        /// True to draw over the area of movement with the background color.
+        draw_background: bool,
+    },
 }
 
 /// Text parser. Turns a string into a stream of [`Token`] objects.
@@ -90,13 +92,11 @@ where
 pub(crate) const SPEC_CHAR_NBSP: char = '\u{a0}';
 pub(crate) const SPEC_CHAR_ZWSP: char = '\u{200b}';
 pub(crate) const SPEC_CHAR_SHY: char = '\u{ad}';
-pub(crate) const SPEC_CHAR_ESCAPE: char = '\x1b';
 
 fn is_word_char(c: char) -> bool {
     // Word tokens are terminated when a whitespace, zwsp or shy character is found. An exception
     // to this rule is the nbsp, which is whitespace but is included in the word.
-    (!c.is_whitespace() || c == SPEC_CHAR_NBSP)
-        && ![SPEC_CHAR_ZWSP, SPEC_CHAR_SHY, SPEC_CHAR_ESCAPE].contains(&c)
+    (!c.is_whitespace() || c == SPEC_CHAR_NBSP) && ![SPEC_CHAR_ZWSP, SPEC_CHAR_SHY].contains(&c)
 }
 
 fn is_space_char(c: char) -> bool {
@@ -185,14 +185,6 @@ where
                             string.get_unchecked(0..c.len_utf8())
                         },
                     )),
-                    #[cfg(feature = "ansi")]
-                    SPEC_CHAR_ESCAPE => ansi_parser::parse_escape(string).map_or(
-                        Some(Token::EscapeSequence(AnsiSequence::Escape)),
-                        |(string, output)| {
-                            self.inner = string.chars();
-                            Some(Token::EscapeSequence(output))
-                        },
-                    ),
 
                     // count consecutive whitespace
                     _ => {
@@ -320,76 +312,3 @@ mod test {
         );
     }
 }
-
-#[cfg(all(feature = "ansi", test))]
-mod ansi_parser_tests {
-
-    use super::{test::assert_tokens, Token};
-    use ansi_parser::AnsiSequence;
-    use heapless::Vec;
-
-    #[test]
-    fn escape_char_ignored_if_not_ansi_sequence() {
-        assert_tokens(
-            "foo\x1bbar",
-            vec![
-                Token::Word("foo"),
-                Token::EscapeSequence(AnsiSequence::Escape),
-                Token::Word("bar"),
-            ],
-        );
-
-        assert_tokens(
-            "foo\x1b[bar",
-            vec![
-                Token::Word("foo"),
-                Token::EscapeSequence(AnsiSequence::Escape),
-                Token::Word("[bar"),
-            ],
-        );
-
-        // can escape the escape char
-        assert_tokens(
-            "foo\x1b\x1bbar",
-            vec![
-                Token::Word("foo"),
-                Token::EscapeSequence(AnsiSequence::Escape),
-                Token::Word("bar"),
-            ],
-        );
-    }
-
-    #[test]
-    fn escape_char_colors() {
-        assert_tokens(
-            "foo\x1b[34mbar",
-            vec![
-                Token::Word("foo"),
-                Token::EscapeSequence(AnsiSequence::SetGraphicsMode(
-                    Vec::from_slice(&[34]).unwrap(),
-                )),
-                Token::Word("bar"),
-            ],
-        );
-        assert_tokens(
-            "foo\x1b[95mbar",
-            vec![
-                Token::Word("foo"),
-                Token::EscapeSequence(AnsiSequence::SetGraphicsMode(
-                    Vec::from_slice(&[95]).unwrap(),
-                )),
-                Token::Word("bar"),
-            ],
-        );
-        assert_tokens(
-            "foo\x1b[48;5;16mbar",
-            vec![
-                Token::Word("foo"),
-                Token::EscapeSequence(AnsiSequence::SetGraphicsMode(
-                    Vec::from_slice(&[48, 5, 16]).unwrap(),
-                )),
-                Token::Word("bar"),
-            ],
-        );
-    }
-}