Fix resolution on Atom editor

[azu]

@takuyaa Hi, I fixed require("kuromoji"); // undefeined issue on some env like Atom.

Purpose

Currently, kuromoji.js doesn't work on Atom editor(plugin).
This pull request fix this issue.

require("kuromoji"); // undefeined in Atom.

Changes

• Remove window detection from src/kuromoji.js and DictionaryLoader
• Split up DictionaryLoader into BrowserDictionaryLoader and NodeDictionaryLoader

Atom has window object... it means that module.exports = undefined @ src/kuromoji.js

I refactor this feature detection and move feature detection to browserify's build phase.
(So, feature detection code was removed)

• src/ code use directly NodeDictionaryLoader.
• dist/browser/kuromoji.js use directly BrowserDictionaryLoader ( dist/browser/kuromoji.js doesn't contain NodeDictionaryLoader)

I'v added a macro that replace NodeDictionaryLoader to BrowserDictionaryLoader into gulpfile.js and package.json

[azu]

Browser use BrowserDictionaryLoader.js (dist/browser/kuromoji.js)

[azu]

browser field spec for package.json

[takuyaa]

I don't know about browser field in details, but if this line is replaced by

"./src/loader/NodeDictionaryLoader.js": "./src/loader/BrowserDictionaryLoader.js"

, perhaps we don't need this line of code in gulpfile.js:

b.require(__dirname + "/src/loader/BrowserDictionaryLoader.js", {expose: "./loader/NodeDictionaryLoader.js"});

(I think browserify will make this rearrangement)

[azu]

Edit: Ah, I agree with that.
But, this change cause external transform not work.

---

browser field for external.(This affect external browserify command)

external is a user that use kuromoji as a module.

b.require for internal.(This affect only gulp build)

[takuyaa]

Hmm... gulp build does not seem to need b.require in my environment.

my package.json:

  "browser": {
    "./src/loader/NodeDictionaryLoader.js": "./src/loader/BrowserDictionaryLoader.js"
  },

my gulpfile.js:

    var b = browserify({
        entries: ["./src/kuromoji.js"],
        standalone: "kuromoji" // window.kuromoji
    });
    // Commented out b.require
    // b.require(__dirname + "/src/loader/BrowserDictionaryLoader.js", {expose: "./loader/NodeDictionaryLoader.js"});
    b.bundle()
        .pipe(source("kuromoji.js"))
        .pipe(gulp.dest("./dist/browser/"));

I executed

$ gulp build

then I got preferred dist/browser/kuromoji.js with BrowserDictionaryLoader.

[takuyaa]

https://twitter.com/azu_re/status/666661814801997824

[takuyaa]

I got it!
b.require is needed for such that modules:

1. require kuromoji.js (in node.js manner)
2. are browserified (for working on browser)
   (but not tested... If you encountered problems, please open an issue)

[takuyaa]

Thanks a lot @azu
This is pretty good PR and some tests on my browsers work well.
I never known about browser field, but it seems to be suitable in this situation.

I have a question or comment on this point.
I'd like to get your opinion about that.

[azu]

Thanks!
I can't wait for new release!