src/cargo/ops/cargo_fetch.rs

   1 use crate::core::compiler::{BuildConfig, CompileMode, RustcTargetData};
   2 use crate::core::{PackageSet, Resolve, Workspace};
   3 use crate::ops;
   4 use crate::util::CargoResult;
   5 use crate::util::Config;
   6 use std::collections::HashSet;
   7
   8 pub struct FetchOptions<'a> {
   9     pub config: &'a Config,
  10     /// The target arch triple to fetch dependencies for
  11     pub targets: Vec<String>,
  12 }
  13
  14 /// Executes `cargo fetch`.
  15 pub fn fetch<'a>(
  16     ws: &Workspace<'a>,
  17     options: &FetchOptions<'a>,
  18 ) -> CargoResult<(Resolve, PackageSet<'a>)> {
  19     ws.emit_warnings()?;
  20     let (packages, resolve) = ops::resolve_ws(ws)?;
  21
  22     let jobs = Some(1);
  23     let config = ws.config();
  24     let build_config = BuildConfig::new(config, jobs, &options.targets, CompileMode::Build)?;
  25     let data = RustcTargetData::new(ws, &build_config.requested_kinds)?;
  26     let mut fetched_packages = HashSet::new();
  27     let mut deps_to_fetch = ws.members().map(|p| p.package_id()).collect::<Vec<_>>();
  28     let mut to_download = Vec::new();
  29
  30     while let Some(id) = deps_to_fetch.pop() {
  31         if !fetched_packages.insert(id) {
  32             continue;
  33         }
  34
  35         to_download.push(id);
  36         let deps = resolve
  37             .deps(id)
  38             .filter(|&(_id, deps)| {
  39                 deps.iter().any(|d| {
  40                     // If no target was specified then all dependencies are
  41                     // fetched.
  42                     if options.targets.is_empty() {
  43                         return true;
  44                     }
  45
  46                     // Otherwise we only download this dependency if any of the
  47                     // requested platforms would match this dependency. Note
  48                     // that this is a bit lossy because not all dependencies are
  49                     // always compiled for all platforms, but it should be
  50                     // "close enough" for now.
  51                     build_config
  52                         .requested_kinds
  53                         .iter()
  54                         .any(|kind| data.dep_platform_activated(d, *kind))
  55                 })
  56             })
  57             .map(|(id, _deps)| id);
  58         deps_to_fetch.extend(deps);
  59     }
  60     packages.get_many(to_download)?;
  61
  62     Ok((resolve, packages))
  63 }