test + bugfix for chunkinto

packages/core/test/pattern.test.mjs

@@ -1271,4 +1271,27 @@ describe('Pattern', () => {
       );
     });
   });
+  describe('unjoin', () => {
+    it('destructures a pattern into subcycles', () => {
+      sameFirst(
+        fastcat('a', 'b', 'c', 'd').unjoin(fastcat(true, fastcat(true, true))).fmap(fast(2)).join(),
+        fastcat('a', 'b', 'a', 'b', 'c', 'c', 'd', 'd')
+      )
+    })
+  })
+  describe('into', () => {
+    it('applies a function to subcycles of a pattern', () => {
+      sameFirst(
+        fastcat('a', 'b', 'c', 'd').into(fastcat(fastcat('true', 'true'), 'true'), fast(2)),
+        fastcat('a', 'a', 'b', 'b', 'c', 'd', 'c', 'd')
+      )
+    })
+  }),
+    describe('chunkinto', () => {
+      it('chunks into subcycles', () => {
+        sameFirst(fastcat('a', 'b', 'c').chunkInto(3, fast(2)).fast(3),
+          fastcat(fastcat('a', 'a'), 'b', 'c', 'a', fastcat('b', 'b'), 'c', 'a', 'b', fastcat('c', 'c'))
+        )
+      })
+    })
 });