leave more characters unescaped for segments (#75)

treat `;,:@&=+$-_.!~*()` characters as safe to be part of segment

Readme.md

@@ -185,6 +185,9 @@ toPath({ id: 123 }) //=> "/user/123"
 toPath({ id: 'café' }) //=> "/user/caf%C3%A9"
 toPath({ id: '/' }) //=> "/user/%2F"
 
+toPath({ id: ':' }) //=> "/user/%3A"
+toPath({ id: ':' }, { pretty: true }) //=> "/user/:"
+
 var toPathRepeated = pathToRegexp.compile('/:segment+')
 
 toPathRepeated({ segment: 'foo' }) //=> "/foo"
@@ -194,7 +197,7 @@ var toPathRegexp = pathToRegexp.compile('/user/:id(\\d+)')
 
 toPathRegexp({ id: 123 }) //=> "/user/123"
 toPathRegexp({ id: '123' }) //=> "/user/123"
-toPathRegexp({ id: 'abc' }) //=> throws TypeError
+toPathRegexp({ id: 'abc' }) //=> Throws `TypeError`.
 ```
 
 **Note:** The generated function will throw on invalid input. It will do all necessary checks to ensure the generated path is valid. This method only works with strings.

index.d.ts

@@ -45,9 +45,13 @@ declare namespace pathToRegexp {
     pattern: string;
   }
 
+  interface PathFunctionOptions {
+    pretty?: boolean;
+  }
+
   export type Token = string | Key;
   export type Path = string | RegExp | Array<string | RegExp>;
-  export type PathFunction = (data?: Object) => string;
+  export type PathFunction = (data?: Object, options?: PathFunctionOptions) => string;
 }
 
 export = pathToRegexp;

index.js

@@ -105,12 +105,24 @@ function parse (str) {
  * Compile a string to a template function for the path.
  *
  * @param  {string}             str
- * @return {!function(Object=)}
+ * @return {!function(Object=, Object=)}
  */
 function compile (str) {
   return tokensToFunction(parse(str))
 }
 
+/**
+ * Encode characters for segment that could cause trouble for parsing.
+ *
+ * @param  {string}
+ * @return {string}
+ */
+function encodeURIComponentPretty (str) {
+  return encodeURI(str).replace(/[/?#'"]/g, function (c) {
+    return '%' + c.charCodeAt(0).toString(16).toUpperCase()
+  })
+}
+
 /**
  * Expose a method for transforming tokens into the path function.
  */
@@ -125,9 +137,11 @@ function tokensToFunction (tokens) {
     }
   }
 
-  return function (obj) {
+  return function (obj, opts) {
     var path = ''
     var data = obj || {}
+    var options = opts || {}
+    var encode = options.pretty ? encodeURIComponentPretty : encodeURIComponent
 
     for (var i = 0; i < tokens.length; i++) {
       var token = tokens[i]
@@ -163,7 +177,7 @@ function tokensToFunction (tokens) {
         }
 
         for (var j = 0; j < value.length; j++) {
-          segment = encodeURIComponent(value[j])
+          segment = encode(value[j])
 
           if (!matches[i].test(segment)) {
             throw new TypeError('Expected all "' + token.name + '" to match "' + token.pattern + '", but received "' + segment + '"')
@@ -175,7 +189,7 @@ function tokensToFunction (tokens) {
         continue
       }
 
-      segment = encodeURIComponent(value)
+      segment = encode(value)
 
       if (!matches[i].test(segment)) {
         throw new TypeError('Expected "' + token.name + '" to match "' + token.pattern + '", but received "' + segment + '"')

test.ts

@@ -398,11 +398,14 @@ var TESTS: Test[] = [
       ['/another', ['/another', 'another']],
       ['/something/else', null],
       ['/route.json', ['/route.json', 'route.json']],
-      ['/something%2Felse', ['/something%2Felse', 'something%2Felse']]
+      ['/something%2Felse', ['/something%2Felse', 'something%2Felse']],
+      ['/something%2Felse%2Fmore', ['/something%2Felse%2Fmore', 'something%2Felse%2Fmore']],
+      ['/;,:@&=+$-_.!~*()', ['/;,:@&=+$-_.!~*()', ';,:@&=+$-_.!~*()']]
     ],
     [
       [{ test: 'route' }, '/route'],
-      [{ test: 'something/else' }, '/something%2Felse']
+      [{ test: 'something/else' }, '/something%2Felse'],
+      [{ test: 'something/else/more' }, '/something%2Felse%2Fmore']
     ]
   ],
   [
@@ -799,12 +802,14 @@ var TESTS: Test[] = [
       }
     ],
     [
-      ['/anything/goes/here', ['/anything/goes/here', 'anything/goes/here']]
+      ['/anything/goes/here', ['/anything/goes/here', 'anything/goes/here']],
+      ['/;,:@&=/+$-_.!/~*()', ['/;,:@&=/+$-_.!/~*()', ';,:@&=/+$-_.!/~*()']]
     ],
     [
       [{ test: '' }, '/'],
       [{ test: 'abc' }, '/abc'],
-      [{ test: 'abc/123' }, '/abc%2F123']
+      [{ test: 'abc/123' }, '/abc%2F123'],
+      [{ test: 'abc/123/456' }, '/abc%2F123%2F456']
     ]
   ],
   [
@@ -1981,6 +1986,16 @@ describe('path-to-regexp', function () {
     })
   })
 
+  describe('compile', function () {
+    it('should allow pretty option', function () {
+      var value = ';,:@&=+$-_.!~*()'
+      var toPath = pathToRegexp.compile('/:value')
+      var path = toPath({ value }, { pretty: true })
+
+      expect(path).to.equal(`/${value}`)
+    })
+  })
+
   describe('compile errors', function () {
     it('should throw when a required param is undefined', function () {
       var toPath = pathToRegexp.compile('/a/:b/c')