Diff

Stand-alone diff implementation.

Generating diff

The Differ class can be used to generate a textual representation of the difference between two strings:

using SebastianBergmann.Diff;

var differ = new Differ();
Console.WriteLine( differ.diff("foo", "bar") );

The code above yields the output below:

--- Original
+++ New
@@ @@
-foo
+bar

There are three output builders available in this package:

UnifiedDiffOutputBuilder

This is default builder, which generates the output close to udiff and is used by PHPUnit.

using SebastianBergmann.Diff;
using SebastianBergmann.Diff.Output;

var builder = new UnifiedDiffOutputBuilder(
    "--- Original
+++ New
", // custom header
    false                      // do not add line numbers to the diff 
);

var differ = new Differ(builder);
Console.WriteLine( $differ.diff("foo", "bar") );

StrictUnifiedDiffOutputBuilder

Generates (strict) Unified diff's (unidiffs) with hunks, similar to diff -u and compatible with patch and git apply.

using SebastianBergmann.Diff;
using SebastianBergmann.Diff.Output;

var builder = new StrictUnifiedDiffOutputBuilder(new PhpArray() {
    { "collapseRanges", true }, // ranges of length one are rendered with the trailing `,1`
    { "commonLineThreshold", 6},    // number of same lines before ending a new hunk and creating a new one (if needed)
    { "contextLines", 3 },    // like `diff:  -u, -U NUM, --unified[=NUM]`, for patch/git apply compatibility best to keep at least @ 3
    { "fromFile", PhpValue.Null },
    { "fromFileDate", PhpValue.Null },
    { "toFile", PhpValue.Null },
    { "toFileDate", PhpValue.Null },
});

var differ = new Differ(builder);
Console.WriteLine( differ.diff("foo", "bar") );

DiffOnlyOutputBuilder

Output only the lines that differ.

using SebastianBergmann.Diff;
using SebastianBergmann.Diff.Output;

var builder = new DiffOnlyOutputBuilder(
    "--- Original
+++ New
"
);

var differ = new Differ(builder);
Console.WriteLine( differ.diff("foo", "bar") );

DiffOutputBuilderInterface

You can pass any output builder to the Differ class as longs as it implements the DiffOutputBuilderInterface.

Parsing diff

The Parser class can be used to parse a unified diff into an object graph:

using SebastianBergmann.Diff;
// using SebastianBergmann;

// var git = new Git('/usr/local/src/money');

//var diff = git.getDiff(
//  "948a1a07768d8edd10dcefa8315c1cbeffb31833",
//  "c07a373d2399f3e686234c4f7f088d635eb9641b"
//);

var parser = new Parser();
var diff = parser.parse(diff);

The code above returns ICollection of SebastianBergmann.Diff.Diff objects.