Adding tests

============

You can test shaping of a unicode sequence against a font like this:

```sh

$ ./hb-unicode-encode 41 42 43 627 | ../../util/hb-shape font.ttf

```

assuming an in-tree build.  The 41 42 43 627 here is a sequence of

Unicode codepoints: U+0041,0042,0043,0627.  When you are happy with

the shape results, you can use the `record-test.sh` script to add

this to the test suite.  `record-test.sh` requires `pyftsubset` to

be installed.  You can get `pyftsubset` by installing

FontTools from <https://github.com/behdad/fonttools>.

To use `record-test.sh`, just put it right before the `hb-shape` invocation:

```sh

$ ./hb-unicode-encode 41 42 43 627 | ./record-test.sh ../../util/hb-shape font.ttf

```

what this does is:

  * Subset the font for the sequence of Unicode characters requested,

  * Compare the `hb-shape` output of the original font versus the subset

    font for the input sequence,

  * If the outputs differ, perhaps it is because the font does not have

    glyph names; it then compares the output of `hb-view` for both fonts.

  * If the outputs differ, recording fails.  Otherwise, it will move the

    subset font file into `fonts/sha1sum` and name it after its hash,

    and prints out the test case input, which you can then redirect to

    an existing or new test file in `tests`, eg.:

```sh

$ ./hb-unicode-encode 41 42 43 627 | ./record-test.sh ../../util/hb-shape font.ttf >> tests/test-name.test

```

If you created a new test file, add it to `Makefile.am` so it is run.

Check that `make check` does indeed run it, and that the test passes.

When everything looks good, `git add` the new font as well as new

test file if you created any.  You can see what new files are there

by running `git status tests fonts/sha1sum`.  And commit!

*Note!*  Please only add tests using Open Source fonts, preferably under

OFL or similar license.