Fix string truncate with max ref. Closes #1826

hapijs · Jun 16, 2019 · 9685eb1 · 9685eb1
1 parent 18b5fe6
commit 9685eb1
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Showing 2 changed files with 41 additions and 2 deletions.
diff --git a/lib/types/string/index.js b/lib/types/string/index.js
@@ -8,6 +8,7 @@ const Hoek = require('@hapi/hoek');
 const Any = require('../any');
 const Common = require('../../common');
 const JoiDate = require('../date');
+const Ref = require('../../ref');
 
 const Ip = require('./ip');
 const Uri = require('./uri');
@@ -120,7 +121,15 @@ internals.String = class extends Any {
         if (this._flags.truncate) {
             const rule = this._uniqueRules.get('max');
             if (rule) {
-                value = value.slice(0, rule.args.limit);        // BUG - issue 1826
+                let limit = rule.args.limit;
+                if (Ref.isRef(limit)) {
+                    limit = limit.resolve(value, state, prefs);
+                    if (!internals.checkLimit(limit)) {
+                        return { value, errors: this.createError('number.ref', limit, { ref: rule.args.limit }, state, prefs) };
+                    }
+                }
+
+                value = value.slice(0, limit);
             }
         }
 
@@ -464,7 +473,7 @@ internals.String = class extends Any {
 
         const refs = {
             limit: {
-                assert: (value) => Number.isSafeInteger(value) && value >= 0,
+                assert: internals.checkLimit,
                 code: 'string.ref',
                 message: 'limit must be a positive integer or reference'
             }
@@ -731,4 +740,10 @@ internals.String.prototype._rules = {
 internals.String.prototype.uuid = internals.String.prototype.guid;
 
 
+internals.checkLimit = function (limit) {
+
+    return Number.isSafeInteger(limit) && limit >= 0;
+};
+
+
 module.exports = new internals.String();
diff --git a/test/types/string.js b/test/types/string.js
@@ -4494,6 +4494,30 @@ describe('string', () => {
                 ['  abcdef  ', true, null, 'aabcd']
             ]);
         });
+
+        it('truncates a string (ref)', () => {
+
+            const ref = Joi.ref('b');
+            const schema = Joi.object({
+                a: Joi.string().max(ref).truncate(),
+                b: Joi.number()
+            });
+
+            Helper.validate(schema, [
+                [{ a: 'abc', b: 4 }, true, null, { a: 'abc', b: 4 }],
+                [{ a: 'abcde', b: 2 }, true, null, { a: 'ab', b: 2 }],
+                [{ a: 'abcdef', b: 5 }, true, null, { a: 'abcde', b: 5 }],
+                [{ a: 'abc' }, false, null, {
+                    message: '"a" references "ref:b" which is not a number',
+                    details: [{
+                        message: '"a" references "ref:b" which is not a number',
+                        path: ['a'],
+                        type: 'number.ref',
+                        context: { key: 'a', label: 'a', ref }
+                    }]
+                }]
+            ]);
+        });
     });
 
     describe('validate()', () => {