Option to provide custom diff

emmetio · Aug 23, 2022 · b8f8e16 · b8f8e16
1 parent 25e4282
commit b8f8e16
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Showing 2 changed files with 16 additions and 5 deletions.
diff --git a/src/diff.ts b/src/diff.ts
@@ -279,12 +279,17 @@ function suppressWhitespace(value: string, pos: number, state: DiffState): boole
 }
 
 function getDiff(from: ParsedModel, to: ParsedModel, options: Options): Diff[] {
-    const dmp = new diff_match_patch();
-    if (options.dmp) {
-        Object.assign(dmp, options.dmp);
+    let diffs: Diff[];
+    if (options.diff) {
+        diffs = options.diff(from.content, to.content, options.dmp);
+    } else {
+        const dmp = new diff_match_patch();
+        if (options.dmp) {
+            Object.assign(dmp, options.dmp);
+        }
+        diffs = dmp.diff_main(from.content, to.content);
+        dmp.diff_cleanupSemantic(diffs);
     }
-    let diffs = dmp.diff_main(from.content, to.content);
-    dmp.diff_cleanupSemantic(diffs);
 
     if (options.replaceThreshold && getChangeThreshold(diffs) > options.replaceThreshold) {
         // Text is too different, mark it as replaced

diff --git a/src/options.ts b/src/options.ts
@@ -1,3 +1,4 @@
+import type { Diff } from 'diff-match-patch';
 import { ScannerOptions, createOptions as scannerOptions } from '@emmetio/html-matcher';
 
 export interface DMPOptions {
@@ -108,6 +109,11 @@ export interface Options extends ScannerOptions {
      * Values vary from 0 to 1, but actual threshold might be larger than 1
      */
     replaceThreshold?: number;
+
+    /**
+     * Custom function to perform diff on given content
+     */
+    diff?: (from: string, to: string, opt?: Partial<DMPOptions>) => Diff[];
 }
 
 const defaultOptions: Partial<Options> = {