Lock times are u32 and can necessitate encoding using 5 bytes. As such
they are "special".
Add methods `push_lock_time` and `push_sequence` for pushing absolute
lock times and sequence numbers. We do not push relative locktimes
because they are only 16 bits from the original sequence number.
Our `script::read_scriptint` function is based on the constructor
code (incl. call to `set_vch`) code from Bitcoin Core. Add rustdoc
comment saying so, emit a link because there are already multiple links
to `script.h` in this file (one just right below the added comment).
We only support reads of upto 4 bytes where as Bitcoin Core allows
reading a `CScriptNum` with more bytes than that. Add a rustdoc
comment (incl. link to Bitcoin Core) mentioning that.
Our `Builder::push_int` method is the same as Bitcoin Core `CScript`
`push_int64` method. We currently use `OP_FALSE` (equivalent to `OP_0`)
but recently we added `OP_0`, lets use it to make our code better mimic
Core (also saves devs checking that `OP_FALSE` is the same as `OP_0`).
The `script` module is large and unwieldy.
Refactor the `script` module, splitting it up into a tree of modules.
Here are a few of the changes and their stated benefits
- Split the two script types out into separate files: Readers of the
methods can then tell immediately from the file name which type they are
reading.
- Put all the impls for the two script types together: Makes parsing the
API easier because one can more quickly see which traits are implemented
on what i.e., all the `AsRef` imlps are grouped together.
- Put the impls for the two script types in order, first `Script` then
`ScriptBuf`: Makes it easier for us to see if we missed something.
- Put the `Builder` and `Instruction` (and associated) types in their
own modules: Some devs find long files hard to navigate, so far there
hasn't been too much push back against short files.
- Put tests in a separate file: This idea was recently discussed.
This is only moving code and fixing import statements etc. No other
changes to the code.