Merge 71215bc into 6a01ba8

index.js

@@ -19,17 +19,27 @@ function removeTrailingSlashes(opts) {
         }
 
         let path;
+        let querystring = '';
 
         // We have already done a redirect and we will continue if we are in chained mode
         if (opts.chained && ctx.status === 301) {
-            path = getPath(ctx.response.get('Location'), ctx.querystring);
+            const location = ctx.response.get('Location') || '';
+
+            // We can't use ctx.querystring because it may not be up to date
+            const parsedLocation = location.match(/\?(.*)$/);
+            if (parsedLocation && parsedLocation[1]) {
+                querystring = parsedLocation[1];
+            }
+
+            path = getPath(location, querystring);
         } else if (ctx.status !== 301) {
+            querystring = ctx.querystring;
             path = getPath(ctx.originalUrl, ctx.querystring);
         }
 
         if (path && haveSlash(path)) {
             path = path.slice(0, -1);
-            const query = ctx.querystring.length ? '?' + ctx.querystring : '';
+            const query = querystring.length ? '?' + querystring : '';
 
             ctx.status = 301;
             ctx.redirect(path + query);

test/index.js

@@ -68,6 +68,42 @@ describe('koa-remove-trailing-slashes', () => {
                 expect(mock.ctx.status).toBe(301);
             });
 
+            it('should correctly chain redirect if path has trailing slash and query params', async () => {
+                const mock = createMock('/fOo/?baz=1', 'baz=1');
+
+                // Mock that something has made a redirect before us
+                mock.ctx.status = 301;
+                mock.ctx.body = 'Redirecting to …';
+                mock.ctx.response = {
+                    get() {
+                        return '/foo/?bar=1';
+                    }
+                };
+
+                await removeTrailingSlashes()(mock.ctx, mock.next);
+
+                expect(mock.redirectMock.calls[0].arguments[0]).toEqual('/foo?bar=1');
+                expect(mock.ctx.status).toBe(301);
+            });
+
+            it('should not use old query params when processing chain redirects', async () => {
+                const mock = createMock('/fOo/?baz=1', 'baz=1');
+
+                // Mock that something has made a redirect before us
+                mock.ctx.status = 301;
+                mock.ctx.body = 'Redirecting to …';
+                mock.ctx.response = {
+                    get() {
+                        return '/foo/barrr/';
+                    }
+                };
+
+                await removeTrailingSlashes()(mock.ctx, mock.next);
+
+                expect(mock.redirectMock.calls[0].arguments[0]).toEqual('/foo/barrr');
+                expect(mock.ctx.status).toBe(301);
+            });
+
             it('should redirect on url and path has trailing slash', async () => {
                 const mock = createMock('/foo/');
                 await removeTrailingSlashes()(mock.ctx, mock.next);