addon-sdk/source/lib/diffpatcher/Readme.md@b8a032363ba2 (annotated)
addon-sdk/source/lib/diffpatcher/Readme.md
Thu, 22 Jan 2015 13:21:57 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Thu, 22 Jan 2015 13:21:57 +0100
- branch
- TOR_BUG_9701
- changeset 15
- b8a032363ba2
- permissions
- -rw-r--r--
Incorporate requested changes from Mozilla in review:
https://bugzilla.mozilla.org/show_bug.cgi?id=1123480#c6
| michael@0 | 1 | # diffpatcher |
| michael@0 | 2 | |
| michael@0 | 3 | [](http://travis-ci.org/Gozala/diffpatcher) |
| michael@0 | 4 | |
| michael@0 | 5 | [](http://ci.testling.com/Gozala/diffpatcher) |
| michael@0 | 6 | |
| michael@0 | 7 | Diffpatcher is a small library that lets you treat hashes as if they were |
| michael@0 | 8 | git repositories. |
| michael@0 | 9 | |
| michael@0 | 10 | ## diff |
| michael@0 | 11 | |
| michael@0 | 12 | Diff function that takes two hashes and returns delta hash. |
| michael@0 | 13 | |
| michael@0 | 14 | ```js |
| michael@0 | 15 | var diff = require("diffpatcher/diff") |
| michael@0 | 16 | |
| michael@0 | 17 | diff({ a: { b: 1 }, c: { d: 2 } }, // hash#1 |
| michael@0 | 18 | { a: { e: 3 }, c: { d: 4 } }) // hash#2 |
| michael@0 | 19 | |
| michael@0 | 20 | // => { // delta |
| michael@0 | 21 | // a: { |
| michael@0 | 22 | // b: null, // - |
| michael@0 | 23 | // e: 3 // + |
| michael@0 | 24 | // }, |
| michael@0 | 25 | // c: { |
| michael@0 | 26 | // d: 4 // ± |
| michael@0 | 27 | // } |
| michael@0 | 28 | // } |
| michael@0 | 29 | ``` |
| michael@0 | 30 | |
| michael@0 | 31 | As you can see from the example above `delta` makes no real distinction between |
| michael@0 | 32 | proprety upadate and property addition. Try to think of additions as an update |
| michael@0 | 33 | from `undefined` to whatever it's being updated to. |
| michael@0 | 34 | |
| michael@0 | 35 | ## patch |
| michael@0 | 36 | |
| michael@0 | 37 | Patch fuction takes a `hash` and a `delta` and returns a new `hash` which is |
| michael@0 | 38 | just like orginial but with delta applied to it. Let's apply delta from the |
| michael@0 | 39 | previous example to the first hash from the same example |
| michael@0 | 40 | |
| michael@0 | 41 | |
| michael@0 | 42 | ```js |
| michael@0 | 43 | var patch = require("diffpatcher/patch") |
| michael@0 | 44 | |
| michael@0 | 45 | patch({ a: { b: 1 }, c: { d: 2 } }, // hash#1 |
| michael@0 | 46 | { // delta |
| michael@0 | 47 | a: { |
| michael@0 | 48 | b: null, // - |
| michael@0 | 49 | e: 3 // + |
| michael@0 | 50 | }, |
| michael@0 | 51 | c: { |
| michael@0 | 52 | d: 4 // ± |
| michael@0 | 53 | } |
| michael@0 | 54 | }) |
| michael@0 | 55 | |
| michael@0 | 56 | // => { a: { e: 3 }, c: { d: 4 } } // hash#2 |
| michael@0 | 57 | ``` |
| michael@0 | 58 | |
| michael@0 | 59 | That's about it really, just diffing hashes and applying thes diffs on them. |
| michael@0 | 60 | |
| michael@0 | 61 | |
| michael@0 | 62 | ### rebase |
| michael@0 | 63 | |
| michael@0 | 64 | And as Linus mentioned everything in git can be expressed with `rebase`, that |
| michael@0 | 65 | also pretty much the case for `diffpatcher`. `rebase` takes `target` hash, |
| michael@0 | 66 | and rebases `parent` onto it with `diff` applied. |
| michael@0 | 67 | |
| michael@0 | 68 | ## Install |
| michael@0 | 69 | |
| michael@0 | 70 | npm install diffpatcher |
