feat(syntax): Diff highlighting

src/theme/tokens/diff.ts

@@ -0,0 +1,43 @@
+import type { TextmateColors, ThemeContext } from "../../types";
+
+const tokens = (context: ThemeContext): TextmateColors => {
+  const { palette } = context;
+
+  return [
+    {
+      name: "Markup Diff",
+      scope: "markup.changed.diff",
+      settings: {
+        foreground: palette.peach,
+        fontStyle: "",
+      },
+    },
+    {
+      name: "Diff",
+      scope:
+        "meta.diff.header.from-file,meta.diff.header.to-file,punctuation.definition.from-file.diff,punctuation.definition.to-file.diff",
+      settings: {
+        foreground: palette.blue,
+        fontStyle: "",
+      },
+    },
+    {
+      name: "Diff Inserted",
+      scope: "markup.inserted.diff",
+      settings: {
+        foreground: palette.green,
+        fontStyle: "",
+      },
+    },
+    {
+      name: "Diff Deleted",
+      scope: "markup.deleted.diff",
+      settings: {
+        foreground: palette.red,
+        fontStyle: "",
+      },
+    },
+  ];
+};
+
+export default tokens;

src/theme/tokens/index.ts

@@ -3,6 +3,7 @@ import type { ThemeContext } from "../../types";
 import cpp from "./cpp";
 import css from "./css";
 import data from "./data";
+import diff from "./diff";
 import dotenv from "./dotenv";
 import golang from "./golang";
 import graphql from "./graphql";
@@ -292,6 +293,7 @@ export default (context: ThemeContext) => {
       cpp,
       css,
       data,
+      diff,
       dotenv,
       golang,
       graphql,