Closes#14298
This commit adds support for fetching dependencies over git+http(s)
using a minimal implementation of the Git protocols and formats relevant
to fetching repository data.
Git URLs can be specified in `build.zig.zon` as follows:
```zig
.xml = .{
.url = "git+https://github.com/ianprime0509/zig-xml#7380d59d50f1cd8460fd748b5f6f179306679e2f",
.hash = "122085c1e4045fa9cb69632ff771c56acdb6760f34ca5177e80f70b0b92cd80da3e9",
},
```
The fragment part of the URL may specify a commit ID (SHA1 hash), branch
name, or tag. It is an error to omit the fragment: if this happens, the
compiler will prompt the user to add it, using the commit ID of the HEAD
commit of the repository (that is, the latest commit of the default
branch):
```
Fetch Packages... xml... /var/home/ian/src/zig-gobject/build.zig.zon:6:20: error: url field is missing an explicit ref
.url = "git+https://github.com/ianprime0509/zig-xml",
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
note: try .url = "git+https://github.com/ianprime0509/zig-xml#dfdc044f3271641c7d428dc8ec8cd46423d8b8b6",
```
This implementation currently supports only version 2 of Git's wire
protocol (documented in
[protocol-v2](https://git-scm.com/docs/protocol-v2)), which was first
introduced in Git 2.19 (2018) and made the default in 2.26 (2020).
The wire protocol behaves similarly when used over other transports,
such as SSH and the "Git protocol" (git:// URLs), so it should be
reasonably straightforward to support fetching dependencies from such
URLs if the necessary transports are implemented (e.g. #14295).
(Unmanaged)ArrayList.insert has the same inefficiency as the old insertSlice. With the new addManyAt, the solution is trivial.
Also improves the test "growing memory preserves contents". In the previous implementation, if any changes were made to the ArrayList memory growth policy (function growMemory), the list could end up with enough capacity to not trigger a memory growth, defeating the purpose of the test. The new implementation more robustly triggers a memory growth.
These are an order of magnitude quicker than the previous
implementations:
A relative comparison of each, measuring scanning a 1G file.
Reading 1G (1.0000000009313226GiB)
std.mem.sliceTo: 281.232ms
vectorized.sliceTo: 24.769ms
strlen: 24.291ms
std.indexOfScalar: 229.016ms
vectorized.indexOfScalar: 24.685ms
memchr: 24.958ms
* Move `computeBetterCapacity` to the bottom so that `pub` stuff shows
up first.
* Rename `computeBetterCapacity` to `growCapacity`. Every function
implicitly computes something; that word is always redundant in a
function name. "better" is vague. Better in what way? Instead we
describe what is actually happening. "grow".
* Improve doc comments to be very explicit about when element pointers
are invalidated or not.
* Rename `addManyAtIndex` to `addManyAt`. The parameter is named
`index`; that is enough.
* Extract some duplicated code into `addManyAtAssumeCapacity` and make
it `pub`.
* Since I audited every line of code for correctness, I changed the
style to my personal preference.
* Avoid a redundant `@memset` to `undefined` - memory allocation does
that already.
* Fixed comment giving the wrong reason for not calling
`ensureTotalCapacity`.
Includes a more robust implementation of replaceRange, which updates the
ArrayListUnmanaged if state changes in the managed part of the code
before returning an error.
Co-authored-by: Andrew Kelley <andrew@ziglang.org>
This commit makes the following changes:
* Disallow file:/// URIs
* Allow only relative paths in the .path field of build.zig.zon
* Remote now-unneeded shlwapi dependency
