fix: walker was visiting states multiple times

ColinEberhardt · Feb 7, 2021 · 4872cf6 · 4872cf6
1 parent c42d678
commit 4872cf6
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Showing 2 changed files with 7 additions and 1 deletion.
diff --git a/assembly/__tests__/capture-group.spec.ts b/assembly/__tests__/capture-group.spec.ts
@@ -33,3 +33,9 @@ it("should not return captured values for non-matching alternations", () => {
   expect(match.matches[1]).toBe("");
   expect(match.matches[2]).toBe("b");
 });
+
+it("repeated capture groups should return the last match", () => {
+  const match = exec("([a-c])+", "ac");
+  expect(match.matches[0]).toBe("ac");
+  expect(match.matches[1]).toBe("c");
+});
diff --git a/assembly/nfa/walker.ts b/assembly/nfa/walker.ts
@@ -5,8 +5,8 @@ export function walker(
   visitor: (state: State) => void,
   visited: State[] = []
 ): void {
-  visitor(state);
   if (visited.includes(state)) return;
+  visitor(state);
   visited.push(state);
   const nextStates = state.transitions;
   for (let i = 0, len = nextStates.length; i < len; i++) {