Idea for adding diff coloursdiff-colours

Ideas for getting diff colours from the Git config and parsing them
using 'colorparse'.

Leaving this aside and planning to add diff colours by executing
`git-diff` instead. Shelling out to `git diff` would allow us to accept
diff command line options like `--word-diff` and have them work
transparently.

4 files changed, 121 insertions, 0 deletions

diff --git a/Cargo.lock b/Cargo.lock
index e6fd541..b7408da 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -25,6 +25,21 @@ dependencies = [
 ]
 
 [[package]]
+name = "ansi_term"
+version = "0.9.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "23ac7c30002a5accbf7e8987d0632fa6de155b7c3d39d0067317a391e00a2ef6"
+
+[[package]]
+name = "ansi_term"
+version = "0.12.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d52a9bb7ec0cf484c551830a7ce27bd20d67eac647e1befb56b0be4ee39a55d2"
+dependencies = [
+ "winapi 0.3.9",
+]
+
+[[package]]
 name = "autocfg"
 version = "1.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -101,6 +116,15 @@ dependencies = [
 ]
 
 [[package]]
+name = "colorparse"
+version = "2.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "179f9a3462d05f4c15041d8ba8bd59534731fe6ddd89a65ca61ec67655f37379"
+dependencies = [
+ "ansi_term 0.9.0",
+]
+
+[[package]]
 name = "crossbeam-deque"
 version = "0.7.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -277,6 +301,8 @@ dependencies = [
 name = "github-suggestion"
 version = "0.1.0"
 dependencies = [
+ "ansi_term 0.12.1",
+ "colorparse",
  "git2",
  "github-rs",
  "regex",
diff --git a/github-suggestion/Cargo.toml b/github-suggestion/Cargo.toml
index 34e197c..0ef1959 100644
--- a/github-suggestion/Cargo.toml
+++ b/github-suggestion/Cargo.toml
@@ -4,6 +4,8 @@ version = "0.1.0"
 edition = "2018"
 
 [dependencies]
+ansi_term = "0.12.1"
+colorparse = "2.0.1"
 git2 = "0.13.8"
 github-rs = "0.7.0"
 regex = "1.3.9"
diff --git a/github-suggestion/src/color.rs b/github-suggestion/src/color.rs
new file mode 100644
index 0000000..5f4e954
--- /dev/null
+++ b/github-suggestion/src/color.rs
@@ -0,0 +1,91 @@
+// Copyright (c) 2020  Teddy Wing
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program. If not, see <https://www.gnu.org/licenses/>.
+
+
+use ansi_term::Style;
+use colorparse;
+use git2;
+use thiserror::Error;
+
+
+#[derive(Debug, Error)]
+pub enum Error {
+    #[error(transparent)]
+    Git(#[from] git2::Error),
+}
+
+
+static SLOTS: [&'static str; 6] = [
+    "commit",
+    "context",
+    "frag",
+    "func",
+    "old",
+    "new",
+];
+
+
+#[derive(Debug, Default)]
+pub struct Diff {
+    context: Option<Style>,
+    meta: Option<Style>,
+    frag: Option<Style>,
+    func: Option<Style>,
+    old: Option<Style>,
+    new: Option<Style>,
+    commit: Option<Style>,
+    whitespace: Option<Style>,
+    oldMoved: Option<Style>,
+    newMoved: Option<Style>,
+    oldMovedDimmed: Option<Style>,
+    oldMovedAlternative: Option<Style>,
+    oldMovedAlternativeDimmed: Option<Style>,
+    newMovedDimmed: Option<Style>,
+    newMovedAlternative: Option<Style>,
+    newMovedAlternativeDimmed: Option<Style>,
+}
+
+
+// pub fn diff(config: &git2::Config) -> Diff {
+//     let diff = Diff::default();
+//
+//     for slot in SLOTS {
+//         let colors = match config.get_string(slot) {
+//             Ok(c) => c,
+//             Err(e) if e.code() == git2::ErrorCode::NotFound => return Ok(None),
+//             Err(e) => return Err(Error::Git(e)),
+//         };
+//
+//         colorparse::parse(colors)?;
+//     }
+// }
+
+impl Diff {
+    pub fn from_config(config: &git2::Config) -> Result<Self, Error> {
+        let diff = Self::default();
+
+        for slot in &SLOTS {
+            let colors = match config.get_string(slot) {
+                Ok(c) => c,
+                Err(e) if e.code() == git2::ErrorCode::NotFound => return Ok(None),
+                Err(e) => return Err(Error::Git(e)),
+            };
+
+            colorparse::parse(&colors)?;
+        }
+
+        Ok(diff)
+    }
+}
diff --git a/github-suggestion/src/lib.rs b/github-suggestion/src/lib.rs
index 3ec6f00..b7e54cc 100644
--- a/github-suggestion/src/lib.rs
+++ b/github-suggestion/src/lib.rs
@@ -20,6 +20,8 @@
 pub mod client;
 pub mod suggestion;
 
+pub(crate) mod color;
+
 mod url;
 
 pub use crate::client::Client;