ctx.response.get - use .getHeader (#1392)

* use .getHeader

* add tests

Co-authored-by: jongleberry <[email protected]>

lib/response.js

@@ -417,12 +417,12 @@ module.exports = {
    *     // => "text/plain"
    *
    * @param {String} field
-   * @return {String}
+   * @return {any}
    * @api public
    */
 
-  get (field) {
-    return this.header[field.toLowerCase()] || ''
+  get(field) {
+    return this.res.getHeader(field);
   },
 
   /**

test/response/get.js

@@ -0,0 +1,37 @@
+
+'use strict';
+
+const assert = require('assert');
+const context = require('../helpers/context');
+
+describe('ctx.get(name)', () => {
+  it('should get a field value, case insensitive', () => {
+    const ctx = context();
+    ctx.set('X-Foo', 'bar');
+    assert.strictEqual(ctx.response.get('x-FOO'), 'bar');
+  });
+
+  it('should have the same behavior as ctx.res.getHeader on undefined and null values', () => {
+    const ctx = context();
+    ctx.res.setHeader('X-Foo', undefined);
+    ctx.response.header['x-boo'] = null;
+    assert.strictEqual(ctx.response.get('x-FOO'), ctx.res.getHeader('X-FOO'));
+    assert.strictEqual(ctx.response.get('x-bOO'), ctx.res.getHeader('X-BOO'));
+  });
+
+  it('should not convert header value type', () => {
+    const ctx = context();
+    ctx.res.setHeader('Foo-date', new Date());
+    ctx.response.header['foo-map'] = new Map();
+    ctx.res.setHeader('Foo-empty-string', '');
+    ctx.res.setHeader('Foo-number', 0);
+    ctx.res.setHeader('Foo-null', null);
+    ctx.res.setHeader('Foo-undefined', undefined);
+    assert.ok(ctx.response.get('foo-Date') instanceof Date);
+    assert.ok(ctx.response.get('foo-Map') instanceof Map);
+    assert.strictEqual(ctx.response.get('Foo-empty-String'), '');
+    assert.strictEqual(ctx.response.get('Foo-Number'), 0);
+    assert.ok(ctx.response.get('foo-NULL') === null);
+    assert.ok(typeof ctx.response.get('FOO-undefined') === 'undefined');
+  });
+});