Support negative ignore patterns

src/index.ts

@@ -100,12 +100,14 @@ function processPatterns(
 
   const matchPatterns: string[] = [];
   const ignorePatterns: string[] = [];
+  const unignorePatterns: string[] = [];
 
   for (const pattern of ignore) {
-    // don't handle negated patterns here for consistency with fast-glob
     if (!pattern.startsWith('!') || pattern[1] === '(') {
       const newPattern = normalizePattern(pattern, expandDirectories, cwd, properties, true);
       ignorePatterns.push(newPattern);
+    } else {
+      unignorePatterns.push(pattern.slice(1));
     }
   }
 
@@ -119,7 +121,7 @@ function processPatterns(
     }
   }
 
-  return { match: matchPatterns, ignore: ignorePatterns };
+  return { match: matchPatterns, ignore: ignorePatterns, unignore: unignorePatterns };
 }
 
 // TODO: this is slow, find a better way to do this
@@ -152,10 +154,13 @@ function crawl(options: GlobOptions, cwd: string, sync: boolean) {
 
   const processed = processPatterns(options, cwd, properties);
 
+  const unignoreMatcher = processed.unignore.length === 0 ? undefined : picomatch(processed.unignore)
+
   const matcher = picomatch(processed.match, {
     dot: options.dot,
     nocase: options.caseSensitiveMatch === false,
-    ignore: processed.ignore
+    ignore: processed.ignore,
+    onIgnore: unignoreMatcher ? (result => unignoreMatcher(result.output)) : undefined
   });
 
   const exclude = picomatch(processed.ignore, {

test/index.test.ts

@@ -320,11 +320,9 @@ test('negative absolute patterns in options', async () => {
   assert.deepEqual(files2.sort(), ['a/b.txt', 'b/b.txt']);
 });
 
-// can't easily make them properly work right now
-// but at least it's consistent with fast-glob this way
 test('negative patterns in ignore are ignored', async () => {
   const files = await glob({ patterns: ['**/*'], ignore: ['**/b.txt', '!a/b.txt'], cwd });
-  assert.deepEqual(files.sort(), ['a/a.txt', 'b/a.txt']);
+  assert.deepEqual(files.sort(), ['a/a.txt', 'a/b.txt', 'b/a.txt']);
 
   const files2 = await glob({ patterns: ['**/*', '!**/b.txt', '!!a/b.txt'], cwd });
   assert.deepEqual(files2.sort(), ['a/a.txt', 'b/a.txt']);