rrbutani

"""Starlark version of `new_local_repository` for module extensions.

Currently `native.new_local_repository` cannot be called from Bazel module
extensions: https://github.com/bazelbuild/bazel/issues/15412

The plan is to eventually "starlark-ify" this rule:
  - https://docs.google.com/document/d/17RZKMuMjAIgNfFdrsLhqNsMTQDSS-BBA-S-fCSBPV7M/edit
  - https://github.com/bazelbuild/bazel/issues/18285

In the interim we've got our own Starlark-native `new_local_repository`

rrbutani

We couldn’t find that file to show.

rrbutani

Meant to be used together with this Bazel fork:
  - https://github.com/rrbutani/bazel/compare/70fc57d29ce21204f28f8462627badbd5b750787...b8553d4fcf157acddbac855a3945c74d0f962c27

rrbutani

"""Helper functions for repository rules that ensure labels are well-formed.

Labels constructed and used within repository rules do not have their name (the
part after `:`) checked against the package structure of the repo they point to;
they are allowed to refer to source artifacts via paths that do not respect the
package structure or visibility.

For example, for a source file that lives at `@foo//bar/baz:some/file/path`, all
of the following — when passed to repository context functions like `rctx.path`
or `rctx.read` — will refer to the file, without error:

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First you need to run echo "test" > /tmp/foo.

Running bazel build @repo//... will print "running repo rule".

Touching test_file and then bazel build @repo//... will not do anything; the repo rule is not rerun and the artifacts in @repo are not rebuilt.

Modifying test_file will cause the workspace rule to be rerun.

• if you make a change that yields a different BUILD.bazel file then artifacts will be rebuilt (i.e. changing the first line of test_file)
• if you make a change that still yields the same BUILD.bazel file no actions will be run (i.e adding extra lines, whitespace to test_file)

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{ lib }: {
  # Given an attrset of derivations of interest, returns an attrset where each
  # corresponding key is the full list of deps for the derivation.
  #
  # Note: this is far from perfect; this function only walks the usual
  # `mkDerivation` dependency list attributes so it'll miss dependencies in
  # strings.
  collectDeps = pkgSet: let
    # dbg = x: builtins.trace (builtins.typeOf x) (builtins.trace x x);
    d = path: builtins.unsafeDiscardStringContext path;

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...

see the revision history for lock files, if required

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{ lib ? import <nixpkgs/lib>, pkgs ? import <nixpkgs> { config.checkMeta = true; }, config ? pkgs.config }: let

  extendedMetaAttrs = [ "agsRoles" ];

  removeExtendedFromMeta = attrs: attrs // (lib.optionalAttrs (attrs ? meta) {
    meta = builtins.removeAttrs attrs.meta extendedMetaAttrs;
  });
  getExtendedMeta = attrs: lib.filterAttrs
    (n: _: builtins.elem n extendedMetaAttrs)
    (attrs.meta or {})

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{ pkgs ? import ./. {} }: let
  overlay = f: p: let base = p.llvmPackages_15; in {
    llvmPackages_15 = let
      patch = f.fetchpatch {
        url = "https://github.com/llvm/llvm-project/commit/57c7bb3ec89565c68f858d316504668f9d214d59.patch";
        hash = "sha256-AaM9A6tQ4YAw7uDqCIV4VaiUyLZv+unwcOqbakwW9/k=";
        relative = "libcxx";
      };

      tools = base.tools;

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// We want to slice and dice our opcode map on:
//  - opcode byte
//  - opcode map (aka leading opcode bytes; if present)
//  - prefixes
//
// Unfortunately, C doesn't have pattern matching. The macros that follow are
// our (unfortunate) facsimile.
//
// Essentially we are — in the style of `disas_insn` — appropriating the upper