Sanitize strings

Calling String on an object with a toString property would throw an error

3 files changed, 87 insertions, 77 deletions

diff --git a/lib/render-msg.js b/lib/render-msg.js
index 277b419..4b8c8c0 100644
--- a/lib/render-msg.js
+++ b/lib/render-msg.js
@@ -124,7 +124,7 @@ RenderMsg.prototype.wrap = function (content, cb) {
   var ts = this.msg.value.timestamp
   var date = ts ? new Date(ts) : null
   var self = this
-  var channel = this.c.channel ? '#' + this.c.channel : ''
+  var channel = this.c.channel ? '#' + u.toString(this.c.channel) : ''
   var done = multicb({pluck: 1, spread: true})
   done()(null, [h('tr.msg-row',
     h('td.msg-left',
@@ -399,7 +399,7 @@ RenderMsg.prototype.markdown = function (cb) {
 
 RenderMsg.prototype.markdownSource = function (text, mentions) {
   return h('div',
-    h('pre', String(text)),
+    h('pre', u.toString(text)),
     mentions ? [
       h('div', h('em', 'mentions:')),
       this.valueTable(mentions, 2, function () {})
@@ -478,7 +478,7 @@ RenderMsg.prototype.getName = function (id, cb) {
     case '%': return this.getMsgName(id, cb)
     case '@': // fallthrough
     case '&': return this.getAboutName(id, cb)
-    default: return cb(null, String(id))
+    default: return cb(null, u.toString(id))
   }
 }
 
@@ -557,7 +557,7 @@ RenderMsg.prototype.title1 = function (cb) {
 
 RenderMsg.prototype.getAboutName = function (id, cb) {
   this.app.getAbout(id, function (err, about) {
-    cb(err, about && about.name || (String(id).substr(0, 8) + '…'))
+    cb(err, about && about.name || (u.toString(id).substr(0, 8) + '…'))
   })
 }
 
@@ -643,7 +643,7 @@ RenderMsg.prototype.about = function (cb) {
       isSelf ?
         'self-identifies as ' :
         ['identifies ', h('a', {href: this.toUrl(this.c.about)}, u.truncate(this.c.about, 10)), ' as '],
-      h('ins', String(this.c.name))
+      h('ins', u.toString(this.c.name))
     ], cb)
   }
 
@@ -705,20 +705,20 @@ RenderMsg.prototype.about = function (cb) {
         : h('a', {href: this.toUrl(this.c.about)}, u.truncate(this.c.about, 10)),
       ': '
     ],
-    this.c.name ? [h('ins', String(this.c.name)), ' '] : '',
-    this.c.title ? h('h3', String(this.c.title)) : '',
+    this.c.name ? [h('ins', u.toString(this.c.name)), ' '] : '',
+    this.c.title ? h('h3', u.toString(this.c.title)) : '',
     this.c.series || this.c.seriesNo ? this.renderSeries(this.c) : '',
-    this.c.authors ? h('div', h('em', {title: 'authors'}, String(this.c.authors))) : '',
+    this.c.authors ? h('div', h('em', {title: 'authors'}, u.toString(this.c.authors))) : '',
     this.c.rating || this.c.ratingMax || this.c.ratingType ? h('div', [
       'rating: ',
-      String(this.c.rating),
+      u.toString(this.c.rating),
       this.c.ratingMax ? '/' + this.c.ratingMax : '',
       this.c.ratingType ? [' ',
         h('span', {innerHTML: u.unwrapP(this.render.markdown(this.c.ratingType))})
       ] : ''
     ]) : '',
-    this.c.genre ? h('div', ['genre: ', h('u', String(this.c.genre))]) : '',
-    this.c.shelve ? h('div', ['shelf: ', h('u', String(this.c.shelve))]) : '',
+    this.c.genre ? h('div', ['genre: ', h('u', u.toString(this.c.genre))]) : '',
+    this.c.shelve ? h('div', ['shelf: ', h('u', u.toString(this.c.shelve))]) : '',
     this.c.description ? h('div',
       {innerHTML: this.render.markdown(this.c.description)}) : '',
     this.c.review ? h('blockquote',
@@ -786,7 +786,7 @@ RenderMsg.prototype.contact = function (cb) {
         ' ', a,
         self.c.note ? [
           ' from ',
-          h('code', String(self.c.note))
+          h('code', u.toString(self.c.note))
         ] : '',
         self.c.reason ? [' because ',
           h('q', {innerHTML: u.unwrapP(self.render.markdown(self.c.reason))})
@@ -808,7 +808,7 @@ RenderMsg.prototype.pub = function (cb) {
 
 RenderMsg.prototype.address = function (cb) {
   var availability = this.c.availability * 100
-  var addr = u.extractHostPort(this.value.author, String(this.c.address))
+  var addr = u.extractHostPort(this.value.author, u.toString(this.c.address))
   addr = this.app.removeDefaultPort(addr)
   this.wrapMini([
     'has address',
@@ -832,7 +832,7 @@ RenderMsg.prototype.pubOwnerAnnounce = function (cb) {
 RenderMsg.prototype.pubOwnerConfirm = function (cb) {
   var self = this
   var announcement = this.c.announcement
-  var addr = u.extractHostPort(this.value.author, String(this.c.address))
+  var addr = u.extractHostPort(this.value.author, u.toString(this.c.address))
   addr = this.app.removeDefaultPort(addr)
   this.wrap([
     'confirms pub ownership announcement ',
@@ -906,18 +906,18 @@ RenderMsg.prototype.gitRepo = function (cb) {
   var name = self.c.name
   var upstream = self.c.upstream
   self.link(upstream, function (err, upstreamA) {
-    if (err) upstreamA = ('a', {href: self.toUrl(upstream)}, String(name))
+    if (err) upstreamA = ('a', {href: self.toUrl(upstream)}, u.toString(name))
     self.wrapMini([
       upstream ? ['forked ', upstreamA, ': '] : '',
       'git clone ',
       h('code', h('small', 'ssb://' + id)),
-      name ? [' ', h('a', {href: self.toUrl(id)}, String(name))] : ''
+      name ? [' ', h('a', {href: self.toUrl(id)}, u.toString(name))] : ''
     ], cb)
   })
 }
 
 function asString(str) {
-  return str ? String(str) : str
+  return str ? u.toString(str) : str
 }
 
 RenderMsg.prototype.gitUpdate = function (cb) {
@@ -953,8 +953,8 @@ RenderMsg.prototype.gitUpdate = function (cb) {
           var path = '/git/commit/' + encodeURIComponent(commit.sha1)
             + '?msg=' + encodeURIComponent(self.msg.key)
           return h('li', commit.sha1 ? [h('a', {href: self.render.toUrl(path)},
-            h('code', String(commit.sha1).substr(0, 8))), ' '] : '',
-            commit.title ? self.linkify(String(commit.title)) : '',
+            h('code', u.toString(commit.sha1).substr(0, 8))), ' '] : '',
+            commit.title ? self.linkify(u.toString(commit.title)) : '',
             self.render.gitCommitBody(commit.body)
           )
         })) : '',
@@ -964,11 +964,11 @@ RenderMsg.prototype.gitUpdate = function (cb) {
             + '?msg=' + encodeURIComponent(self.msg.key)
           return h('li',
             h('a', {href: self.render.toUrl(path)},
-              h('code', String(tag.sha1).substr(0, 8))), ' ',
-            'tagged ', String(tag.type), ' ',
-            h('code', String(tag.object).substr(0, 8)), ' ',
-            String(tag.tag),
-            tag.title ? [': ', self.linkify(String(tag.title).trim()), ' '] : '',
+              h('code', u.toString(tag.sha1).substr(0, 8))), ' ',
+            'tagged ', u.toString(tag.type), ' ',
+            h('code', u.toString(tag.object).substr(0, 8)), ' ',
+            u.toString(tag.tag),
+            tag.title ? [': ', self.linkify(u.toString(tag.title).trim()), ' '] : '',
             tag.body ? self.render.gitCommitBody(tag.body) : ''
           )
         })) : '',
@@ -991,9 +991,9 @@ RenderMsg.prototype.gitPullRequest = function (cb) {
     if (err) return cb(err)
     self.wrap(h('div.ssb-pull-request',
       'pull request ',
-      'to ', baseRepoLink, ':', String(self.c.branch), ' ',
-      'from ', headRepoLink, ':', String(self.c.head_branch),
-      self.c.title ? h('h4', String(self.c.title)) : '',
+      'to ', baseRepoLink, ':', u.toString(self.c.branch), ' ',
+      'from ', headRepoLink, ':', u.toString(self.c.head_branch),
+      self.c.title ? h('h4', u.toString(self.c.title)) : '',
       h('div', {innerHTML: self.markdown()})), cb)
   })
 }
@@ -1004,7 +1004,7 @@ RenderMsg.prototype.issue = function (cb) {
     if (err) return cb(err)
     self.wrap(h('div.ssb-issue',
       'issue on ', projectLink,
-      self.c.title ? h('h4', String(self.c.title)) : '',
+      self.c.title ? h('h4', u.toString(self.c.title)) : '',
       h('div', {innerHTML: self.markdown()})), cb)
   })
 }
@@ -1082,7 +1082,7 @@ RenderMsg.prototype.valueTable = function (val, depth, cb) {
             )
           } else if (isContent && key === 'type') {
             // TODO: also link to images by type, using links2
-            var type = String(val.type)
+            var type = u.toString(val.type)
             return h('tr',
               h('td', h('strong', 'type')),
               h('td', h('a', {href: self.toUrl('/type/' + type)}, type))
@@ -1105,7 +1105,7 @@ RenderMsg.prototype.valueTable = function (val, depth, cb) {
         type: 'checkbox', disabled: 'disabled', checked: val ? 'checked' : undefined
       })
     default:
-      return cb(), String(val)
+      return cb(), u.toString(val)
   }
 }
 
@@ -1129,8 +1129,8 @@ RenderMsg.prototype.issues = function (cb) {
   }
   var els = issues.map(function (issue) {
     var commit = issue.object || issue.label ? [
-      issue.object ? h('code', String(issue.object)) : '', ' ',
-      issue.label ? h('q', String(issue.label)) : ''] : ''
+      issue.object ? h('code', u.toString(issue.object)) : '', ' ',
+      issue.label ? h('q', u.toString(issue.label)) : ''] : ''
     if (issue.merged === true)
       return h('div',
         'merged ', self.link1(issue, done()))
@@ -1142,7 +1142,7 @@ RenderMsg.prototype.issues = function (cb) {
         'reopened ', self.link1(issue, done()))
     if (typeof issue.title === 'string')
       return h('div',
-        'renamed ', self.link1(issue, done()), ' to ', h('ins', String(issue.title)))
+        'renamed ', self.link1(issue, done()), ' to ', h('ins', u.toString(issue.title)))
   })
   done(cb)
   return els.length > 0 ? [els, h('br')] : ''
@@ -1172,11 +1172,11 @@ RenderMsg.prototype.repost = function (cb) {
 }
 
 RenderMsg.prototype.update = function (cb) {
-  var id = String(this.c.update)
+  var id = u.toString(this.c.update)
   this.wrapMini([
     h('div', 'updated ', h('code.ssb-id',
       h('a', {href: this.render.toUrl(id)}, id))),
-    this.c.title ? h('h4.msg-title', String(this.c.title)) : '',
+    this.c.title ? h('h4.msg-title', u.toString(this.c.title)) : '',
     this.c.description ? h('div',
       {innerHTML: this.render.markdown(this.c.description)}) : ''
   ], cb)
@@ -1209,7 +1209,7 @@ RenderMsg.prototype.fermentAudio = function (cb) {
       : ''),
     h('td',
       h('a', {href: this.render.toUrl(this.c.audioSrc)},
-        String(this.c.title)),
+        u.toString(this.c.title)),
       isFinite(this.c.duration)
         ? ' (' + formatDuration(this.c.duration) + ')'
         : '',
@@ -1233,7 +1233,7 @@ RenderMsg.prototype.musicRelease = function (cb) {
             }))
           : ''),
       h('td',
-        h('h4.msg-title', String(this.c.title)),
+        h('h4.msg-title', u.toString(this.c.title)),
         this.c.text
           ? h('div', {innerHTML: this.render.markdown(this.c.text)})
           : ''
@@ -1242,7 +1242,7 @@ RenderMsg.prototype.musicRelease = function (cb) {
     h('ul', u.toArray(this.c.tracks).filter(Boolean).map(function (track) {
       return h('li',
         h('a', {href: self.render.toUrl(track.link)},
-          String(track.fname)))
+          u.toString(track.fname)))
     }))
   ], cb)
 }
@@ -1255,10 +1255,10 @@ RenderMsg.prototype.dns = function (cb) {
   self.wrap([
     h('div',
       h('p',
-        h('ins', {title: 'name'}, String(record.name)), ' ',
-        h('span', {title: 'ttl'}, String(record.ttl)), ' ',
-        h('span', {title: 'class'}, String(record.class)), ' ',
-        h('span', {title: 'type'}, String(record.type))
+        h('ins', {title: 'name'}, u.toString(record.name)), ' ',
+        h('span', {title: 'ttl'}, u.toString(record.ttl)), ' ',
+        h('span', {title: 'class'}, u.toString(record.class)), ' ',
+        h('span', {title: 'type'}, u.toString(record.type))
       ),
       h('pre', {title: 'data'},
         JSON.stringify(record.data || record.value, null, 2)),
@@ -1288,12 +1288,12 @@ RenderMsg.prototype.wifiNetwork = function (cb) {
 
 RenderMsg.prototype.mutualCredit = function (cb) {
   var self = this
-  var currency = String(self.c.currency)
+  var currency = u.toString(self.c.currency)
   self.link(self.c.account, function (err, a) {
     if (err) return cb(err)
     self.wrapMini([
       'credits ', a || '?', ' ',
-      h('code', String(self.c.amount)), ' ',
+      h('code', u.toString(self.c.amount)), ' ',
       currency[0] === '#'
         ? h('a', {href: self.toUrl(currency)}, currency)
         : h('ins', currency),
@@ -1361,7 +1361,7 @@ RenderMsg.prototype.npmPublish = function (cb) {
     self.wrap([
       h('div',
         'published ',
-        h('u', String(pkg.name)), ' ',
+        h('u', u.toString(pkg.name)), ' ',
         hJoin(versions.map(function (version) {
           var distTag = distTagged[version]
           return [h('b', version), distTag ? [' (', h('i', distTag), ')'] : '']
@@ -1473,7 +1473,7 @@ function parseFenRank (line) {
 }
 
 function parseChess(fen) {
-  var fields = String(fen).split(/\s+/)
+  var fields = u.toString(fen).split(/\s+/)
   var ranks = fields[0].split('/')
   var f2 = fields[2] || ''
   return {
@@ -1644,7 +1644,7 @@ RenderMsg.prototype.chessChat = function (cb) {
     if (err) return cb(err)
     self.wrap([
       h('div', h('small', '> ', rootLink)),
-      h('p', String(self.c.msg))
+      h('p', u.toString(self.c.msg))
     ], cb)
   })
 }
@@ -1705,7 +1705,7 @@ RenderMsg.prototype.acmeChallengesHttp01 = function (cb) {
         href: 'http://' + challenge.domain +
           '/.well-known/acme-challenge/' + challenge.token,
         title: challenge.keyAuthorization,
-      }, String(challenge.domain))
+      }, u.toString(challenge.domain))
     }), ', ', ', and ')
   ), cb)
 }
@@ -1732,10 +1732,10 @@ RenderMsg.prototype.bookclub = function (cb) {
         }))
       })),
     h('td',
-      h('h4', String(props.title)),
+      h('h4', u.toString(props.title)),
       props.series || props.seriesNo ? self.renderSeries(props) : '',
       props.authors ?
-        h('p', h('em', String(props.authors)))
+        h('p', h('em', u.toString(props.authors)))
         : '',
       props.description
         ? h('div', {innerHTML: self.render.markdown(props.description)})
@@ -1773,7 +1773,7 @@ RenderMsg.prototype.sombrioScore = function (cb) {
   var self = this
   self.wrapMini(h('span',
     'scored ',
-    h('ins', String(self.c.score))
+    h('ins', u.toString(self.c.score))
   ), cb)
 }
 
@@ -1794,8 +1794,8 @@ RenderMsg.prototype.blog = function (cb) {
       }) : 'blog'),
     h('td',
       blogId ? h('h3', h('a', {href: self.render.toUrl('/markdown/' + blogId)},
-        String(self.c.title || self.msg.key))) : '',
-      String(self.c.summary || ''))
+        u.toString(self.c.title || self.msg.key))) : '',
+      u.toString(self.c.summary || ''))
   )), cb)
 }
 
@@ -1809,8 +1809,8 @@ RenderMsg.prototype.imageMap = function (cb) {
       u.toArray(self.c.areas).map(function (areaLink) {
         var href = areaLink && self.toUrl(areaLink.link)
         return href ? h('area', {
-          shape: String(areaLink.shape),
-          coords: String(areaLink.coords),
+          shape: u.toString(areaLink.shape),
+          coords: u.toString(areaLink.coords),
           href: href,
         }) : ''
       })
@@ -1819,7 +1819,7 @@ RenderMsg.prototype.imageMap = function (cb) {
       src: self.render.imageUrl(imgRef),
       width: Number(imgLink.width) || undefined,
       height: Number(imgLink.height) || undefined,
-      alt: String(imgLink.name || ''),
+      alt: u.toString(imgLink.name || ''),
       usemap: '#' + mapName,
     }) : ''
   ]), cb)
@@ -1829,7 +1829,7 @@ RenderMsg.prototype.skillCreate = function (cb) {
   var self = this
   self.wrapMini(h('span',
     ' created skill ',
-    h('ins', String(self.c.name))
+    h('ins', u.toString(self.c.name))
   ), cb)
 }
 
@@ -1861,7 +1861,7 @@ RenderMsg.prototype.identitySkillAssign = function (cb) {
     self.wrapMini(h('span',
       self.c.action === 'assign' ? 'assigns '
         : self.c.action === 'unassign' ? 'unassigns '
-        : h('code', String(self.c.action)), ' ',
+        : h('code', u.toString(self.c.action)), ' ',
       'skill ', a
     ), cb)
   })
@@ -1876,7 +1876,7 @@ RenderMsg.prototype.ideaSkillAssign = function (cb) {
     self.wrapMini(h('span',
       self.c.action === 'assign' ? 'assigns '
         : self.c.action === 'unassign' ? 'unassigns '
-        : h('code', String(self.c.action)), ' ',
+        : h('code', u.toString(self.c.action)), ' ',
       'skill ', skillA,
       ' to idea ',
       ideaA
@@ -1890,7 +1890,7 @@ RenderMsg.prototype.ideaAssocate = function (cb) {
     self.wrapMini(h('span',
       self.c.action === 'associate' ? 'associates with '
         : self.c.action === 'disassociate' ? 'disassociates with '
-        : h('code', String(self.c.action)), ' ',
+        : h('code', u.toString(self.c.action)), ' ',
       'idea ', a
     ), cb)
   })
@@ -1902,7 +1902,7 @@ RenderMsg.prototype.ideaHat = function (cb) {
     self.wrapMini(h('span',
       self.c.action === 'take' ? 'takes '
         : self.c.action === 'discard' ? 'discards '
-        : h('code', String(self.c.action)), ' ',
+        : h('code', u.toString(self.c.action)), ' ',
       'idea ', a
     ), cb)
   })
@@ -1922,7 +1922,7 @@ RenderMsg.prototype.ideaUpdate = function (cb) {
   if (keys === 'title') {
     return self.wrapMini(h('span',
       'titles idea ',
-      h('a', {href: self.toUrl(self.c.ideaKey)}, String(props.title))
+      h('a', {href: self.toUrl(self.c.ideaKey)}, u.toString(props.title))
     ), cb)
   }
 
@@ -1938,7 +1938,7 @@ RenderMsg.prototype.ideaUpdate = function (cb) {
   if (keys === 'description,title') {
     return self.wrap(h('div',
       'describes idea ',
-      h('a', {href: self.toUrl(self.c.ideaKey)}, String(props.title)),
+      h('a', {href: self.toUrl(self.c.ideaKey)}, u.toString(props.title)),
       ':',
       h('blockquote', {innerHTML: self.render.markdown(props.description)})
     ), cb)
@@ -1974,7 +1974,7 @@ RenderMsg.prototype.aboutResource = function (cb) {
   var self = this
   return self.wrap(h('div',
     'describes resource ',
-    h('a', {href: self.toUrl(self.c.about)}, String(self.c.name)),
+    h('a', {href: self.toUrl(self.c.about)}, u.toString(self.c.name)),
     ':',
     h('blockquote', {innerHTML: self.render.markdown(self.c.description)})
   ), cb)
@@ -1995,11 +1995,11 @@ RenderMsg.prototype.lineComment = function (cb) {
         },
           updateMsg && updateMsg.value.timestamp
             ? htime(new Date(updateMsg.value.timestamp))
-            : String(self.c.updateId)
+            : u.toString(self.c.updateId)
         ), ' ',
         h('a', {
           href: self.toUrl('/git/commit/' + self.c.commitId + '?msg=' + encodeURIComponent(self.c.updateId))
-        }, String(self.c.commitId).substr(0, 8)), ' ',
+        }, u.toString(self.c.commitId).substr(0, 8)), ' ',
         h('a', {
           href: self.toUrl('/git/line-comment/' +
             encodeURIComponent(self.msg.key || JSON.stringify(self.msg)))
@@ -2061,16 +2061,16 @@ RenderMsg.prototype.poll = function (cb) {
         return h('div',
           pollType === 'chooseOne' ? [
             h('input', {type: 'radio', name: 'poll_choice', value: i}), ' ',
-            String(choice)
+            u.toString(choice)
           ] : pollType === 'meetingTime' /*|| pollType === 'dot'*/ ? [
             h('input', {type: 'checkbox', name: 'poll_choices', value: i}), ' ',
             dateSpan(new Date(choice))
             /*
           ] : pollType === 'range' ? [
             h('input', {type: 'number', name: 'poll_choice_' + i, min: 0, max: max}), ' ',
-            String(choice)
+            u.toString(choice)
             */
-          ] : String(choice)
+          ] : u.toString(choice)
         )
       }),
       pollType === 'meetingTime' ? '' : h('p', 'reason: ',
@@ -2119,7 +2119,7 @@ RenderMsg.prototype.pollPosition = function (cb) {
       h('ul', pickedChoices.map(function (choice) {
         return h('li',
           positionType === 'meetingTime' ? dateSpan(new Date(choice))
-          : String(choice)
+          : u.toString(choice)
         )
       })),
       reason ? h('div', {innerHTML: self.render.markdown(reason, self.c.mentions)}) : ''
@@ -2153,7 +2153,7 @@ RenderMsg.prototype.pollResolution = function (cb) {
       h('ul', pickedChoices.map(function (choice) {
         return h('li',
           pollType === 'meetingTime' ? dateSpan(new Date(choice))
-          : String(choice)
+          : u.toString(choice)
         )
       }))
     ), cb)
@@ -2163,7 +2163,7 @@ RenderMsg.prototype.pollResolution = function (cb) {
 RenderMsg.prototype.scat = function (cb) {
   this.wrapMini([
     this.c.action ? '' : 'chats ',
-    h('q', String(this.c.text))
+    h('q', u.toString(this.c.text))
   ], cb)
 }
 
@@ -2174,16 +2174,16 @@ RenderMsg.prototype.share = function (cb) {
     self.wrapMini([
       'shares ',
       share.content === 'blog' ? 'blog '
-        : share.content ? [h('code', String(share.content)), ' ']
+        : share.content ? [h('code', u.toString(share.content)), ' ']
         : '',
-      link || String(share.link),
+      link || u.toString(share.link),
       share.url ? [
         ' at ',
         h('small', h('a', {href: self.toUrl(share.url)}, share.url))
       ] : '',
       share.text ? [
         ': ',
-        h('q', String(share.text))
+        h('q', u.toString(share.text))
       ] : ''
     ], cb)
   })
@@ -2216,7 +2216,7 @@ RenderMsg.prototype.label = function (cb) {
       'labeled ',
       link,
       ' as ',
-      h('ins', String(self.c.label))
+      h('ins', u.toString(self.c.label))
     ], cb)
   })
 }
diff --git a/lib/render.js b/lib/render.js
index 1aec728..e694396 100644
--- a/lib/render.js
+++ b/lib/render.js
@@ -190,7 +190,7 @@ Render.prototype.markdown = function (text, mentions, opts) {
   var out = ssbcMd ? md.block(String(text), {
     toUrl: function (ref) { return self.toUrl(ref) },
     imageLink: function (ref) { return self.imageUrl(ref) }
-  }) : marked(String(text), this.markedOpts)
+  }) : marked(u.toString(text), this.markedOpts)
   delete this._mentions
   delete this._mentionsByLink
   return out //fixSymbols(out)
diff --git a/lib/util.js b/lib/util.js
index 731cc82..c5584ee 100644
--- a/lib/util.js
+++ b/lib/util.js
@@ -93,6 +93,16 @@ u.toLinkArray = function (x) {
   return u.toArray(x).map(u.toLink).filter(u.linkDest)
 }
 
+u.toString = function (str) {
+  switch (typeof str) {
+    case 'string': return str
+    case 'object':
+      if (str !== null) return JSON.stringify(str)
+    default:
+      return String(str)
+  }
+}
+
 u.renderError = function(err) {
   return h('div.error',
     h('h3', err.name),