fgnass / diffparser

Unified diff parser for Node and the browser

Unified diff parser for Node and the browser

This project is a ES2015 version of https://github.com/sergeyt/parse-diff.

It comes with a full test suite and in addition to line numbers also provides position information as required by the GitHub Comments API.

import parse from 'diffparser';

const diff = `
diff --git a/file b/file
index 123..456 789
--- a/file
+++ b/file
@@ -1,2 +1,2 @@
- line1
+ line2
`;

parse(diff);

This will return an array (one entry per file) with the following structure:

[
  {
    "from": "file",
    "to": "file",
    "chunks": [
      {
        "content": "@@ -1,2 +1,2 @@",
        "changes": [
          {
            "type": "del",
            "del": true,
            "oldLine": 1,
            "position": 1,
            "content": "- line1"
          },
          {
            "type": "add",
            "add": true,
            "newLine": 1,
            "position": 2,
            "content": "+ line2"
          }
        ],
        "oldStart": 1,
        "oldLines": 2,
        "newStart": 1,
        "newLines": 2
      }
    ],
    "deletions": 1,
    "additions": 1,
    "index": [
      "123..456",
      "789"
    ]
  }
]

Optional Rename Detection

You can pass { findRenames: true } as option in order to detect renamed files:

const diff = `
diff --git a/bar b/bar
new file mode 100644
index 0000000..4e4b354
--- /dev/null
+++ b/bar
@@ -0,0 +1,2 @@
+this is a
+sample file
diff --git a/foo b/foo
deleted file mode 100644
index 4e4b354..0000000
--- a/foo
+++ /dev/null
@@ -1,2 +0,0 @@
-this is a
-sample file
`;

parse(diff, { findRenames: true });

This will return the following array:

[
  {
    "renamed": true,
    "from": "foo",
    "to": "bar"
  }
]

License

MIT

diffparser's Issues

Update ESLint

I'd like to update ESLint to the latest version (from v2 to v5) and track that in this issue. Some questions before tackling that:

• ESLint isn't currently enforced for PRs (on Travis). Cool to add an npm script to run this on PRs? (npm run lint)
• The airbnb ESLint plugin is also out of date. Do you have a strong opinion of what ESLint restrictions you'd like to enforce? Perhaps using a community standard like standard could be an option?
• Do you have a preference on using something like prettier to enforce a consistent code style (which can also be integrated with ESLint)?

Line number does not consider context

Input:

@@ -36,6 +36,7 @@ export type SomeContext = {
   foo: bar,
 };

+import newdep from 'newdep';
 import {bla} from 'bla';
 import {qwe} from 'qwe';
 import {ertyu} from 'ertyu';

Output:

...
{
      "content": "@@ -36,6 +36,7 @@ export type SomeContext = {",
      "changes": [
        {
          "type": "normal",
          "normal": true,
          "position": 1,
          "content": "   foo: bar,"
        },
        {
          "type": "normal",
          "normal": true,
          "position": 2,
          "content": " };"
        },
        {
          "type": "add",
          "add": true,
          "ln": 36,
          "position": 3,
          "content": "+import newdep from 'newdep';"
        },
        {
          "type": "normal",
          "normal": true,
          "position": 4,
          "content": " import {bla} from 'bla';"
        },
        {
          "type": "normal",
          "normal": true,
          "position": 5,
          "content": " import {qwe} from 'qwe';"
        },
        {
          "type": "normal",
          "normal": true,
          "position": 6,
          "content": " import {ertyu} from 'ertyu';"
        }
      ],
      "oldStart": 36,
      "oldLines": 6,
      "newStart": 36,
      "newLines": 7
    },
...

There are 2 issues here:

1. The ln property is only present for changed lines (type === add/del), but not in lines of type normal.
2. When the ln property is present, it does not consider the number of context lines preceding it, rendering its value inaccurate. In the above example, the line marked with ln: 36 should really be ln: 38.

Ideally, parse would return a consistent format for each changed line, including the ln number, the calculation for which should also consider the extent of the surrounding context.

Parsing this diff fails

Hello,
I've been trying to get this diff parsed but I believe there is something in it that makes it fail.

What I see in my console is the following:

Uncaught (in promise) Error: Objects are not valid as a React child (found: TypeError: Cannot read property 'changes' of null). If you meant to render a collection of children, use an array instead or wrap the object using createFragment(object) from the React add-ons. Check the render method of `DiffViewerMeta`.
    at invariant (invariant.js:44)
    at traverseAllChildrenImpl (traverseAllChildren.js:144)
    at traverseAllChildren (traverseAllChildren.js:172)
    at flattenChildren (flattenChildren.js:66)
    at ReactDOMComponent._reconcilerUpdateChildren (ReactMultiChild.js:202)
    at ReactDOMComponent._updateChildren (ReactMultiChild.js:310)
    at ReactDOMComponent.updateChildren (ReactMultiChild.js:297)
    at ReactDOMComponent._updateDOMChildren (ReactDOMComponent.js:942)
    at ReactDOMComponent.updateComponent (ReactDOMComponent.js:760)
    at ReactDOMComponent.receiveComponent (ReactDOMComponent.js:722)

Do you have documentation on how to contribute? Thanks.